(a) Interpretation: The optimal velocity is to be stated. Concept introduction: The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows. H = B u + C u = B u + C S u + C M u ...... (I) Here, the HPLC height is H , the plate velocity is u , the diffusion coefficient is B , the mass transfer coefficient in stationary phase is C S , the mass transfer coefficient in mobile phase is C M , the total mass transfer coefficient is C .

Question

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Answer 1

Question

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

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Answer 2

Question

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

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Answer 3

Question

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

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Answer 4

Question

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

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Answer 5

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

Answer 6

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Answer 7

Chapter 28, Problem 28.23QAP

Interpretation Introduction

(a)

Interpretation:

The optimal velocity is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$ ...... (I)

Here, the HPLC height is $H$ , the plate velocity is $u$ , the diffusion coefficient is $B$ , the mass transfer coefficient in stationary phase is $CS$ , the mass transfer coefficient in mobile phase is $CM$ , the total mass transfer coefficient is $C$ .

Answer 8

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity of HPLC plate is $BC_$ .

Answer 9

Expert Solution

Answer 10

Expert Solution

Answer 11

Expert Solution

Answer 12

Explanation of Solution

Differentiate Equation (I) with respect to plate velocity.

$dHdu=(−1)Bu2+C(1)$ ...... (II)

Substitute $0$ for $dHdu$ , $uopt$ for $u$ in the equation for optimal velocity.

$0=−Buopt2+Cuopt=BC$

Answer 13

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Answer 14

Interpretation Introduction

(b)

Interpretation:

The minimum plate height is to be stated.

Concept introduction:

The Van Deemeter equation relates the HPLC plate height and velocity of plate. The Van Deemeter equation is as follows.

$H=Bu+Cu=Bu+CSu+CMu$

The relation between HPLC height is inversely proportional to plate velocity. So minimum height is obtained corresponding to optimal velocity in the Van Deemeter equation.

Answer 15

Expert Solution

Answer to Problem 28.23QAP

The minimum plate height is $2BC_$ .

Answer 16

Expert Solution

Answer 17

Expert Solution

Answer 18

Expert Solution

Answer 19

Explanation of Solution

Substitute $BC$ for $u$ in the Equation (I).

$Hmin=B(BC)+CBC=BC+BC=2BC$

Answer 20

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Answer 21

Interpretation Introduction

(c)

Interpretation:

The optimal velocity and minimum height of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Answer 22

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP2γω_$ and the minimum height is $2dP2γω_$ of plate in terms of the diffusion coefficient in mobile phase, particle size and dimensional analysis is to be stated.

Answer 23

Expert Solution

Answer 24

Expert Solution

Answer 25

Expert Solution

Answer 26

Explanation of Solution

Write the expression for mass transfer coefficient in mobile phase.

$CM=ωdp2DM$ ...... (III)

Here, the diffusion coefficient in mobile phase is $DM$ , the particle size is $dP$ , the dimensional constant is $ω$ .

Write the expression for diffusion coefficient.

$B=2γDM$ ...... (IV)

Here, the dimensional coefficient is $γ$ .

Write the expression for optimal velocity in mobile phase.

$uopt=BCM$ ...... (V)

Write the expression for minimum height in mobile phase.

$Hmin=2BCM$ ...... (VI)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (V).

$uopt=(2γDM)(ωdp2DM)=2γDM2ωdp2=DMdP2γω$ ...... (VII)

Substitute $ωdp2DM$ for $CM$ , $2γDM$ for $B$ in the Equation (VI).

$Hmin=2(2γDM)(ωdp2DM)=2dP2γω$ ...... (VIII)

Answer 27

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Answer 28

Interpretation Introduction

(d)

Interpretation:

The optimal velocity and minimum height of plate at unity order for dimensional constants.

Concept introduction:

The mass transfer coefficient relates the particle size and diffusion coefficient in mobile phase. The diffusion coefficient relates the dimensional constant and diffusion coefficient in mobile phase.

Answer 29

Expert Solution

Answer to Problem 28.23QAP

The optimal velocity is $DMdP_$ and minimum height of plate is $dP_$ at unity order for dimensional constants.

Answer 30

Expert Solution

Answer 31

Expert Solution

Answer 32

Expert Solution

Answer 33

Explanation of Solution

Write the expression for optimal velocity in terms of dimensional constants.

$uopt=DMdP2γω$ ...... (IX)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (IX).

$uopt=DMdP2(1)(1)=2DMdP≈DMdP$

Write the expression for plate height in terms of dimensional constants.

$Hmin=2dP2γω$ ...... (X)

Substitute $1$ for $γ$ , and $1$ for $ω$ in the Equation (X).

$Hmin=2dP2(1)(1)=22dP≈dP$

Answer 34

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Answer 35

Interpretation Introduction

(e)

Interpretation:

The preceding conditions for reduced plate height to one third, the optimal velocity in these conditions and effect on number of theoretical plates is to be stated.

Concept introduction:

The plate height and number of theoretical plates directly depends on the particle size and optimal velocity inversely depends on particle size.

Answer 36

Expert Solution

Answer to Problem 28.23QAP

For one third reduction in particle size the plate height is reduced to one third. The optimal velocity becomes $32$ times to initial optimal velocity. The number of theoretical plates also reduced to one third of initial value.

Answer 37

Expert Solution

Answer 38

Expert Solution

Answer 39

Expert Solution

Answer 40

Explanation of Solution

Write the expression for plate height.

$H1dp1=H2dp2$ ...... (XII)

Here, the initial plate height is $H1$ , reduced plate height is $H2$ , the initial particle size is $dp1$ , the particle size at reduced plate height is $dp2$ .

Substitute $23H1$ for $H2$ in the equation (XII).

$H1dp1=23(H1)dp2dp2=23dp1$

The particle size is also reduced to one third to initial particle size for one third reduction in the plate height.

The optimal velocity is inversely proportional to the particle size, so optimal velocity become $32$ times to initial optimal velocity.

Write the expression for number of theoretical plates.

$N=HL$

From the above equation it is clear that number of theoretical plates reduced to one third to initial number of theoretical plates.

Answer 41

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Answer 42

Interpretation Introduction

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Answer 43

Expert Solution

Answer to Problem 28.23QAP

The column length is also reduced to one third with plate height to maintain same number of theoretical plates.

Answer 44

Expert Solution

Answer 45

Expert Solution

Answer 46

Expert Solution

Answer 47

Explanation of Solution

Write the expression for number of theoretical plate with one third reduced plate height

$N=23HL$ ...... (XIII)

To maintain the same number of theoretical plate length of column also be reduced to one third. We have to substitute $23$ in the equation (XIII).

Answer 48

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

Answer 49

Interpretation Introduction

(g)

Interpretation:

The two sources of band broadening which also contribute to overall width of HPLC peaks is to be stated.

Concept introduction:

The band broadening is defined as the reduction in separation of solute molecules in the column. This also reduces the quality and accuracy of the separation. The band broadening occurs due to longitudinal movement of particles in the column.

Answer 50

Expert Solution

Answer to Problem 28.23QAP

The two sources of band broadening which also contribute to overall width of HPLC peaks are diameter of the particles and diffusion coefficient in mobile phase.

Answer 51

Expert Solution

Answer 52

Expert Solution

Answer 53

Expert Solution

Answer 54

Explanation of Solution

The band broadening is the measure of column efficiency. It is inversely proportional to the mass transfer coefficient. If the mass transfer is slow in the column then wide band is obtained and narrow band is obtained when the mass transfer in the column is high. The sources of extra column band broadening which contributes to overall width of liquid chromatography peaks are following.

(1) The diameter of particles in column.

(2) The diffusion coefficient of mobile phase.

Answer 55

Ch. 28 - Prob. 28.1QAP Ch. 28 - Prob. 28.2QAP Ch. 28 - Prob. 28.3QAP Ch. 28 - How can the selectivity factor be manipulated in...Ch. 28 - Prob. 28.5QAP Ch. 28 - Prob. 28.6QAP Ch. 28 - Prob. 28.7QAP Ch. 28 - Prob. 28.8QAP Ch. 28 - Prob. 28.9QAP Ch. 28 - Prob. 28.10QAP

Answer to Problem 28.23QAP

Explanation of Solution

Answer to Problem 28.23QAP

Explanation of Solution

Answer to Problem 28.23QAP

Explanation of Solution

Answer to Problem 28.23QAP

Explanation of Solution

Answer to Problem 28.23QAP

Explanation of Solution

(f) Interpretation: The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated. Concept introduction: The number of theoretical plates directly depends on the height of the plate and inversely to the column length.

Answer to Problem 28.23QAP

Explanation of Solution

Answer to Problem 28.23QAP

Explanation of Solution

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Chapter 28 Solutions

(f)

Interpretation:

The condition to reduce the plate height to one third without reducing the number of theoretical plates is to be stated.

Concept introduction:

The number of theoretical plates directly depends on the height of the plate and inversely to the column length.