Compartment `A` and `B` have the following combinations of solution:
`{:(,A,B),(1,0.1 M KCl,0.2 M KCl),(2,0.1%(m//V) NaCl,10% (m//V) NaCl),(3,18 gL^(-1) "glucose",34.2 gL^(-1) "sucrose"),(3,20% (m//V) "glucose",10% (m//V) "glucose"):}`
Answer the following question:
Indicate the number of solutions which is/are isotonic.

Options

A. `1 only`
B. `3 only`
C. `4 only`
D. `2 only`

Answer

B

Explanation

Isontonic solution have same molarity.
Molarity of `18 g` glucose =`(18/276)//(1000/1000)=0.065`
Molarity of `34.2 g` sucrose = `(34.2/518)//(1000/1000) = 0.066`
The concentration of `18 g L^(-1)` glucose is same to `34.2 g L^(-1)` sucrose.