Sodium oxide reacts with water to produce sodium hydroxide. 20.0 g of sodium oxide is dissolved in 500 mL of water. Neglecting the change in volume, the concentration of the resulting NaOH solution is _______ `xx 10^(-1)M`. (Nearest integer)
[Atomic mass `: a = 23.0, O = 16.0, H = 1.0`]

Answer

13

Explanation

`Na_2O + H_2O rarr 2NaOH `
According to reaction `200/62` mole of `Na_2O` gives `400/62` mole of NaOH
so molarity of NaOH solution is `=(n_(NaOH))/(V_m)xx1000`
`=400/62xx1000/500=800/62=12.9M~~13M`