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. `0.477Mand0.477MM`
B. `0.955Mand1.910`
C. `1.910Mand0.955M`
D. `1.90Mand1.910M`

Answer

C

Explanation

`"Molarity"=(25.3xx1000)/(106xx250)=0.955M`
`Na_(2)CO_(3)to2Na^(+)+CO_(3)^(2-)`
`=2xx0.955+0.955M`
`=1.910M+0.955M`
`:.M_(Na^(+))=2xx0.955=1.910M`
`M_(CO_(3)^(2-))=0.955M`