Sodium oxide reacts with water to produce sodium hydroxide.

Question:

Sodium oxide reacts with water to produce sodium hydroxide. $20.0 \mathrm{~g}$ of sodium oxide is dissolved in $500 \mathrm{~mL}$ of water. Neglecting the change in volume, the concentration of the resulting $\mathrm{NaOH}$ solution is $\times 10^{-1}$ M. (Nearest integer)

$[$ Atomic mass : $\mathrm{Na}=23.0, \mathrm{O}=16.0, \mathrm{H}=1.0]$

Solution:

$\mathrm{Na}_{2} \mathrm{O}+\mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{NaOH}$

$\frac{20}{62}$ moles

Moles of $\mathrm{NaOH}$ formed $=\frac{20}{62} \times 2$

$[\mathrm{NaOH}]=\frac{\frac{40}{62}}{\frac{500}{1000}}=1.29 \mathrm{M}=13 \times 10^{-1} \mathrm{M}$

(Nearest integer)

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Comments

Abhishek mishra
March 9, 2023, 6:49 p.m.
Given :- Na2O = 20.0 g H2O = 500ml = 500/1000= 0.5L REACTION :- Na2O + H2O = 2 NAOH Calculation:- moles of Na2O = 20/62 = 0.3 moles Moles of NAOH = 1/0.3 = 2/x X ( moles) = 0.6 Molarity of solution of NAOH when no volume is changed = 0.6 /0.5 = 1.29 12.9 x 10^-1
Abhishek mishra
March 9, 2023, 6:49 p.m.
Given :- Na2O = 20.0 g H2O = 500ml = 500/1000= 0.5L REACTION :- Na2O + H2O = 2 NAOH Calculation:- moles of Na2O = 20/62 = 0.3 moles Moles of NAOH = 1/0.3 = 2/x X ( moles) = 0.6 Molarity of solution of NAOH when no volume is changed = 0.6 /0.5 = 1.29 12.9 x 10^-1
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