Q. 9.65 - An Introduction to General, Organic, and Biological Chemistry

Question

A $10\% (m/v)$ starch solution is separated from a $1\% (m/v)$ starch solution by a semipermeable membrane. (Starch is a colloid.)

a. Which compartment has the higher osmotic pressure?

b. In which direction will water flow initially?

c. In which compartment will the volume level rise?

Step-by-Step Solution

Answer

(part a) Compartment with $10\% (m/v)$ starch solution has the higher osmotic pressure.

(part b) The water flows from the compartment having $1\% (m/v)$ starch solution to the compartments having $10\% (m/v)$ starch solution.

(part c) In the $10\% (m/v)$ starch solution, the volume level has to be risen.

Step1: Introduction (part a).

When a partially permeable differentiates a solution from pure water, osmotic pressure has been defined as the maximum stress which must be decided to apply to the solution head to avoid fluid movement.

Step2: Given Information (part a, b, c).

The following are the given information:

$10\% (m/v)$ starch solution is separated from $1\% (m/v)$ starch solution.

Step3: Find the Compartment has higher osmotic pressure (part a).

The osmotic pressure inside a solution is based on the concentration of solute particles. The greater the number of disintegrated solute particles, the greater the osmotic pressure.

A $10\% (m/v)$ starch sample containing more dissolved solute particles than a $1\% (m/v)$ starch solution. As a result, the compartment containing a $10\% (m/v)$ starch solution does have the higher osmotic pressure.

Step4: Find the initial water flow direction (part b).

A $10\% (m/v)$ starch solution is applied to one side of a semipermeable membrane, and a $1\% (m/v)$ starch solution is applied to the other. Water molecules can pass through the semipermeable membrane. Starch molecules, on the other hand, are too large to enter through the membrane.

Solute concentration is higher in a $10\% (m/v)$ starch solution than in a $1\% (m/v)$ starch solution. As a result, water flows from the which included the $1\% (m/v)$ starch solution to the which included the $10\% (m/v)$ starch solution, in which the concentration of water is lower.

Step5: Find the compartment of high volume level (part c).

Osmosis occurs when water flows into a solution with a higher solute until the flow of water equalizes in both directions. Water flows first from compartment with the $1\% (m/v)$starch solution to the chamber with the $10\% (m/v)$starch solution.

The addition of water dilutes the $10\% (m/v)$starch solution and attempts to balance the concentrations on the both side of the cell membrane. The volume level of the $10\% (m/v)$starch solution increases as the volume level of the $1\% (m/v)$starch solution decreases.

As a result, the compartment with the $10\% (m/v)$starch solution has a rising volume level.