Chapter 13, Problem 79QRT

Interpretation Introduction

Interpretation:

The osmotic pressure of the blood of cold-blooded animals at $\text{20}\text{.0°C}$ has to be calculated.

Concept introduction

The Freezing point depression ${\text{(ΔT}}_{\text{f}}\text{)}$ is indicated as ${\text{ΔT}}_{\text{f}}{\text{= K}}_{\text{f}}\text{m}$

Where,

${\text{ΔT}}_{\text{f}}-$ Change in freezing point.

${\text{K}}_{\text{f}}-$ Molal freezing point constant.

$m-$ Molality of the solution.

Osmosis is the process by which net movement of solvent into an expense of higher solute concentration via semi permeable membrane.

Osmotic pressure is the pressure that is needed to stop osmosis. Osmotic pressure of the solution is directly proportional to the concentration of the solution. We can calculate osmotic pressure by using this formula is given by,

Osmotic pressure $\text{(π) = iMRT}$

Where,

  ‘i’-Van’t Hoff’s factor.

  M – Molarity of the solution (mol/L).

  R- Ideal gas constant (0.08206${\text{L atm mol}}^{\text{-1}}{\text{K}}^{\text{-1}}$).

  T-Temperature in Kelvin

Moles: One mole is equivalent to the mass of the substance consists same number of units equal to the atoms present in $\text{12}\text{g}$ of ${}^{\text{12}}\text{C}$.

From given mass of substance moles could be calculated by using the following formula,

  $\text{Moles}\text{of}\text{substance }\text{= }\frac{\text{Given}\text{mass}\text{of}\text{substance}}{\text{Molecular}\text{mass}}$

Mass: It is the quantitative measure of a substance. The amount of matter present in substance is expressed as mass. The $S.I.$ unit of mass is $kg$.