The most suitable elution (gradient or isocratic) for the mixture has to be identified. Concept introduction: Running a broad gradient helps us to decide whether to use gradient elution or isocratic elution. This can be decided by the gradient time and the retention time difference. Gradient time is denoted by t G and this is the time over which is required to change the solvent composition. The difference in retention time is denoted by Δ t and this is for the first and last peak obtained in chromatogram. Two conditions are possible by considering the gradient time and retention time difference. This can be given as shown below, Δ t / t G > 0.40 − Gradient Elution Δ t / t G < 0.25 − Isocratic Elution 0.25 < Δ t / t G < 0.40 − Gradient or Isocratic elution Simply to say if all the peaks are eluted over a very narrow solvent range means, the feasible one is isocratic elution. If a wide range of solvent is required means then the practical one that is possible is gradient elution.

Question

Want to see the full answer?

Answer 1

Question

Chapter 25, Problem 25.42P

a)

Interpretation Introduction

Interpretation:

The most suitable elution (gradient or isocratic) for the mixture has to be identified.

Concept introduction:

Running a broad gradient helps us to decide whether to use gradient elution or isocratic elution. This can be decided by the gradient time and the retention time difference.

Gradient time is denoted by tG and this is the time over which is required to change the solvent composition. The difference in retention time is denoted by Δt and this is for the first and last peak obtained in chromatogram.

Two conditions are possible by considering the gradient time and retention time difference. This can be given as shown below,

Δt/tG > 0.40 − Gradient ElutionΔt/tG < 0.25 − Isocratic Elution0.25 < Δt/tG < 0.40 − Gradient or Isocratic elution

Simply to say if all the peaks are eluted over a very narrow solvent range means, the feasible one is isocratic elution. If a wide range of solvent is required means then the practical one that is possible is gradient elution.

b)

Interpretation Introduction

Interpretation:

The starting and ending percentage of Acetonitrile and gradient time has to be given.

Concept introduction:

Running a broad gradient helps us to decide whether to use gradient elution or isocratic elution. This can be decided by the gradient time and the retention time difference.

Gradient time is denoted by tG and this is the time over which is required to change the solvent composition. The difference in retention time is denoted by Δt and this is for the first and last peak obtained in chromatogram.

Two conditions are possible by considering the gradient time and retention time difference. This can be given as shown below,

Δt/tG > 0.40 − Gradient ElutionΔt/tG < 0.25 − Isocratic Elution0.25 < Δt/tG < 0.40 − Gradient or Isocratic elution

Simply to say if all the peaks are eluted over a very narrow solvent range means, the feasible one is isocratic elution. If a wide range of solvent is required means then the practical one that is possible is gradient elution.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

Name 1) 3-fluoro, 1-butene 2) 2-heptene 2,3-difluoro- 1-pentene 4) 6-iodo,4-methyl- 2-decyne 5) 4,4-dibromo- 1,2-butandiol Complete structural formula F -C=C-C-C- Line formula Condensed structural formula N F CH2=CHCHFCH3

1. Part 1: Naming Organic Compounds он H₁C-C-CH3 CH3 Br CI CI 2. Br-CH-CH-CH₂ H₂C-CH-C= -CH-CH2-CH3 3. HC-CH-CH-C-OH 5. H₂C-CH-CH₂-OH 7. OH 4. CH CH₂-CH₂ 6. сно CH-CH-CH-CH₂-CH₂ H₁₂C-CH-CH-CH-CH₁₂-CH₁₂ 8. OH

11 Organic Chemistry Organic Nomenclature Practice Name/Functional Group n-butane Formula Structural Formula (1) C4tt10 H3C C- (2) CH3CH2CH2 CH 3 H₂ -CH3 Н2 name & functional group (1) and (2) OH H₁₂C Н2 name only (1) and (2) name only (1) and (2) H₁C - = - CH₂ Н2 HC=C-C CH3