UNIT 9 TEST REVIEW
1.) A reaction between methane and sulfur produces carbon disulfide (CS2), a liquid often used in the production of cellophane.
___ CH4 + ___ S8 à ___ CS2 + ___ H2S
If 1.50 moles of S8 are used, (A) how many moles of CS2 are produced? (B) How many moles of H2S are produced?
2.) Lead (II) oxide is obtained by roasting galena, lead (II) sulfide, in air.
___ PbS + ___ O2 à ___ PbO + ___ SO2
(A) Determine the theoretical yield (in grams) of PbO if 200.0 grams of PbS are heated.
(B) What is the percent yield if 170.0 grams of PbO are obtained?
3.) Some rockets are fueled by the reaction of hydrazine (N2H2) and hydrogen peroxide (H2O2). How many moles of nitrogen gas can be produced by reacting 255 grams of hydrazine with excess hydrogen peroxide?
___ N2H2 + ___ H2O2 à ___ N2 + ___ H2O
4.) One in a series of reactions that inflate automobile air bags is the decomposition of sodium azide (NaN3).
2 NaN3 à 2 Na + 3 N2
Determine the mass of N2 produced if 100.0 grams of NaN3 are decomposed.
5.) Titanium is a transition metal used in many alloys because it is extremely strong and lightweight. Titanium tetrachloride (TiCl4) is extracted from titanium oxide using chlorine and carbon.
TiO2 + C + 2 Cl2 à TiCl4 + CO2
ANSWERS: 1.) (A) 3.00 moles CS2 (B) 6.00 moles H2S 2.) (A) 186.6 g PbO (B) 91.10 %
3.) 8.50 moles N2 4.) 64.60 g N2 5.) 178 g Cl2