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### 6B.11

Posted: Mon Jan 20, 2020 2:38 am
Hello,
Can someone write out the reaction equation for this problem? I just want to make sure I'm understanding it.
"A student added solid Na2O to a volumetric flask of volume 200.0 mL, which was then filled with water, resulting in 200.0 mL of NaOH solution. Then 5.00 mL of the solution was transferred to another volumetric flask and diluted to 500.0 mL. The pH of the diluted solution is 13.25. (a) What is the molar concentration of hydroxide ions in (i) the diluted solution, (ii) the original solution? (b) What mass of Na2O was added to the first flask?"
Is the reaction Na2O (s) + H2O (l) ⇌ 2Na+ (aq) + 2OH- (aq)

### Re: 6B.11

Posted: Mon Jan 20, 2020 3:06 am
Yes, Na2O (s) + H2O (l) ⇌ 2Na+ (aq) + 2OH- (aq) is the correct reaction

### Re: 6B.11

Posted: Mon Jan 20, 2020 1:28 pm
Sanjana K - 2F wrote:Yes, Na2O (s) + H2O (l) ⇌ 2Na+ (aq) + 2OH- (aq) is the correct reaction

If I broke that reaction into two composite ones, would they be 1) Na2O (s) + H2O (l) -> 2NaOH (aq) and 2) 2NaOH (aq) -> 2Na+ (aq) + 2OH- (aq) ? If so, why doesn't the 2nd reaction not have H20 in the reaction? I tried to write out the 2nd reaction with H20 as a reactant but I couldn't balance the reaction if I did.