Answer to Question #177349 in General Chemistry for mel

Question

Determination of % KPH in unknown mixture

Trail 1:

mass of sample: 0.600 g

buret reading 

final: 16.00 mL

initial: ?

NaOH used: ?

Trail 2:

mass of sample: 0.600 g

buret reading 

final: 15.50 mL

initial: ?

NaOH used: ?

Trail 3:

mass of sample: 0.600 g

buret reading 

final: 15.80 mL

initial: ?

NaOH used: ?

find initial buret reading for trail 1,2,and 3.

calculate mass of KPH and percent KPH.

Answer 1

$$V_{total} = 16.00+15.50+15.80 = 47.3 mL$$

$$\bar{V} = 15.77 mL$$

If c(NaOH) = 0.1M:

$$n(NaOH) = 0.001577 mol$$

$$n(KHP) = 0.001577 mol$$

$$m(KHP) = 204.22g/mol*0.001577 mol = 0.322 g$$

$\%KHP\; =\; 53.67$ %KHP = 53.67%

$$\%KHP\; =\; 53.67$$