Question

Which one of the following pairs of solution can we expect to be isotonic at the same temperature

• A. 0.1 M urea and 0.1 M NaCl
• B. 0.1 M urea and 0.2 M MgCl2
• C. 0.1 M NaCl and 0.1M Na2SO4
• D. 0.1 M Ca(NO3)2 and 0.1 M Na2SO4

Answer 1

The correct option is D

0.1 M Ca(NO3)2 and 0.1 M Na2SO4

Isotonic solutions have same osmotic pressure. The concentration and number of particles should be same, for two solutions to have same osmotic pressure