AP EAMCET2013ChemistrySolutions
Which one of the following is an isotonic pair of solutions?
Options
- A0.15 M NaCl and 0.1 M Na ₂ SO ₄
- B0.2 M Urea and 0.1 M Sugar
- C0.1 MBaCl ₂ and 0.2 M Urea
- D0.4 M MgSO ₄ and 0.1 MNH ₄ Cl
Correct answer
A. 0.15 M NaCl and 0.1 M Na ₂ SO ₄
Step-by-step solution
Two solutions are isotonic if they have same molar concentrations of the particles. (a) 0.15 M NaCl and 0.1 M Na ₂ SO ₄ NaCl is an electrolyte which dissociates to give 2 ions, thus concentration of ions in the solution 0.30 M . Similarly for Na ₂ SO ₄ (3 ions), the concentration of ions in the solution =0.30 M . Hence, both are isotonic.