Which one of the following pair of solutions is an isotonic?

Options

A. 0.15 M NaCl and 0.1 M `Na_(2) SO_(4)`
B. 0.2 M Urea and 0.1 M Sugar
C. 0.1 M `BaCl_(2)` and `0.2` M Urea
D. 0.4 M `MgSO_(4)` and 0.1 `M NH_(4)CI`

Answer

(a)

Explanation

Solutions are said to isotonie if they have same molar concentrations.
`("Concentration of ions in the solution = No.of ions formed" xx "Concentration of solution")`
For `NaCl = 2xx 0.15 0.3 M`
  For `Na_(2) SO_(4) = 3 xx 0.1 = 0.3 M`