Question

Calculate osmotic pressure of $0.585\%$ NaCl solution at $25^\circ C$ .

Answer 1

Hint : In chemistry, a solution is a homogeneous mixture of two or more substances in relative quantities that can be modified continuously up to the solubility limit. The word "solution" is most often associated with the liquid state of matter, but gases and solids may also form solutions.

Complete Step By Step Answer:
The minimum pressure that must be applied to a solution to stop the movement of solvent molecules across a semipermeable membrane is known as osmotic pressure (osmosis). It is a colligative property that is influenced by the solute particle concentration in the solution. The following formula can be used to measure osmotic pressure:
$\pi = iCRT$
Where,
$\pi$ stands for the osmotic pressure,
$i$ stands for van't Hoff factor,
$C$ stands for the solute's molar concentration in the solution.
$R$ stands for the universal gas constant is a constant that describes the behaviour of all gases.
$T$ stands for the temperature.
Jacobus van't Hoff, a Dutch chemist, proposed a relationship between a solution's osmotic pressure and the molar concentration of its solute. It's worth noting that this equation only applies to solutions that behave like ideal ones.
In the question, we should know the value of the above variables to calculate the osmotic factor.
Here, $i =$ $2$ (for NaCl), $R =$ $0.0821$ ${{L.atm} \mathord{\left/ {\vphantom {{L.atm} {molK}}} \right. } {molK}}$ , $T = 27^\circ C = (27 + 273)K = 300K$
In $100$ mL of solution, $0.585$ g of NaCl is dissolved.
The following equation is used to determine the molarity of a solution:
Mass of the solute (NaCl solution) = $0.585g$ (conversion factor: $1g = 1000mg$ )
Molar mass of the NaCl = $58.5{g \mathord{\left/ {\vphantom {g {mol}}} \right. } {mol}}$
Volume of the solution = $100ml$ = $0.1L$ ( $1L = 1000ml$ )
Substitute the values in molarity equation, we get:
Molarity of the solution = $\dfrac{{0.585}}{{58.5{g \mathord{\left/ {\vphantom {g {mol \times 0.1L}}} \right. } {mol \times 0.1L}}}}$ = $0.1$
$\pi = 2 \times 0.1 \times 0.0821 \times 300$ = $4.92atm$
The osmotic pressure of a $0.585\%$ NaCl solution at $27^\circ C$ is $4.92$ atm.

Note :
When a plant receives inadequate water, the cells become hypertonic (they shrink due to loss of water). They wilt and lose their firm, straight posture as a result. The molecular weights of compounds can also be determined by measuring osmotic strain.