If `alpha` is the degree of dissociation of `Na_(2)SO_(4)` the van't Hoff's factor (i) used for calculating the molecular mass is

Options

A. `1+alpha`
B. `1-alpha`
C. `1+2alpha`
D. `1-2alpha`

Answer

C

Explanation

`{:(Na_2SO_4,hArr,2Na^+,+,SO_4^(2-)),(1,,0,,0),(1-alpha,,2alpha,,alpha):}`
van't Hoff factor (i)=`(1-alpha+2alpha+alpha)/1=1+2alpha`