Answer to Question #292220 in General Chemistry for dlofad

Question

find dalta PH of 400 ml , and 1.17 molar NaOH ,when the same amount of ,100 ml of 0.05 Molar NaOH added

Answer 1

Initial pH$=14-(-log\>1.17)$

$=14.068$

Moles of OH$^-$ added

$=\frac{100}{1000}×0.05=0.005$

Moles in 400ml of 1.17 molar NaOH

$=\frac{400}{1000}×1.17=0.468$

Total moles$=0.468+0.005$

$=0.473$

Total volume$=500ml$

Concentration $=\frac{1000}{500}×0.473$

$=0.946$

Final pH$=14-(-log\>0.946)$

$=13.976$

Change in pH$=14.068-13.976$

$=0.092$