5.0 g of sodium hydroxide (molar mass 40 g `mol^(-1)`) is dissolved in little quantity of water and the molarity of the resulting solution?

Options

A. `0.1 mol//dm^(3)`
B. ` 1.0 mol //dm^(3)`
C. `0.125 mol//dm^(3)`
D. ` 1.25mol//dm^(3)`

Answer

D

Explanation

`n=(W)/( M ) = (5)/( 40) =0.125` mole
`M = ( n )/( "Volume of solution") xx1000`
`= ( 0.125 )/( 100) xx 1000= 1.25 mol dm^(-3)`