Question

Compared to $1$M sucrose solution, the ${\psi }_{\omega }$ of $1$M sodium chloride solution is?

• A. High
• B. Same
• C. Lower
• D. None of the above

Answer 1

Answer: (C)

Lower

The difference between water potential of the cell and that of the solution will be higher in case of 1M NaCl solution than 1M sucrose solution. The reason behind this is that although both sucrose and NaCl solutions are of same molarity yet they differ in osmolarity. NaCl completely dissolves in water and forms two types of solutes (Na+and Cl-). Thus 1 M NaCl is equal to 2 osm solution (osmole). Hence osmolarity of 1 M NaCl solution will be twice of that of 1 M sucrose solution.
So, the correct option is C.