First question,
An impure sample of barium hydroxide of mass 1.6524g was allowed to react with 100cm3 of hydrochloric acid of concentration 0.200 M. When the excess acid was titrated against sodium hydroxide, 10.9 cm3 of the sodium hydroxide solution required 28.5 cm3 of the same hydrochloric acid for neutralization in a separate titration. Calculate the percentage of purity of the sample of barium hydroxide.
Second question,
Hydrazine, N2H4 (the 2 and 4 are subscripts) and hydrogen peroxide, H2O2 (the 2s are subscript) are used as rocket reagent in which the mixture of these two substances will produce nitric acid, HNO3 and water.
a) Write a balanced chemical equation for this reaction
b) How many moles of HNO3 will be formed from 3.5g of N2H4(hydrazine)
c) Calculate the number of moles of H2O2 required to react with 22.0g of N2H4
d) How many moles of HNO3 are produced when 30.5g H2O2 is allowed to react with 25.6g of N2H4? Which compound is the limiting reagent?
e) How many grams of the reactant in excess remain after the reaction is completed?
That's all. I have trouble with these 2 questions. Need help....Million thanks in advance!!!
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