25.3 g of sodium carbonate, `Na_(2)CO_(3)` is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ions, `Na^(+)` and carbonate ions, `CO_(3)^(2-)` are respectively (Molar mass of `NaCO_(3)=106g mol^(-1)`)

Options

A. 0.477 M and 0.477 M
B. 0.955 M and 1.910 M
C. 1.910 M and 0.955 M
D. 1.90 M and 1.910 M

Answer

C

Explanation

Molarity of the solution `= (25.3)/(106)xx(1000)/(250)`
`=0.955M`.
`Na_(2)CO_(3)to2Na^(+)+CO_(3)(2-)`
`[Na^(+)] = 2xx0.9555M=1.910M`
`[CO_(3)^(2-)] = 0.955M`