Which of the following aqueous solutions has the highest concentration of `Na^(+)` ?

Options

A. ` 0.304 M Na_(2)SO_(4) `
B. A solution containing `2.06 g NaCl//100mL `
C. A solution having ` 15.4 mg Na^(+)//mL `
D. All have equal` [Na^(+)] `

Answer

C

Explanation

(a) `Na_(2)SO_(4)hArr2Na^(+)+SO_(4)^(2-)`
`:. [Na^(+) = 0.416 M`
(b) ` 2.07 g NaCL//100L =10.5 g NaCl//L =20.7/58.5 = mol L^(-1) `
`=0.353M [Na^(+)] = 0.353 M `
(c)` 15.4 mg Na^(+) =15.4xx10^(-3) g mol Na^(+)L^(-1)`
`=15.4 gNa^(+)L^(-1)= (15.4)/(23) mol Na^(+)L^(-1)`
`:. [Na^(+)] = (15.4)/(23) =0.669 M `