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 ______________ $\times$ 10$-$1 M. (Nearest integer) [Atomic mass : Na = 23.0, O = 16.0, H = 1.0]
Answer (integer)
13
Solution
Na<sub>2</sub>O + H<sub>2</sub>O $\to$ 2NaOH<br><br>${{20} \over {62}}$ moles<br><br>Moles of NaOH formed = ${{20} \over {62}}$ $\times$ 2<br><br>[NaOH] = ${{{{40} \over {62}}} \over {{{500} \over {1000}}}}$ = 1.29 M = 13 $\times$ 10<sup>$-$1</sup> M (Nearest integer)
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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