a. How many atoms of zinc react with 1.49g nitric acid?
b. Calculate the number of grams of zinc that must react with an excess of nitric acid to form 29.1g ammonium nitrate.
10. Hydrazine (N2H4) is used as rocket fuel. It reacts with oxygen to form nitrogen and water.
N2H4 (l) + O2 (g) –>N2 (g) + 2H2O (l)
a. How many liters of nitrogen (at STP) from when 1.0 kg of hydrazine reacts with 1.0 kg of oxygen gas?
b. How many grams of the excess reagent remain after the reaction?
11. When 50.g g of silicon dioxide is heated with an excess of carbon, 32.2g of silicon carbide is produced.
SiO2 (s) + 3C (s) –> SiC (s) + 2CO (g)
a. What is the percent yield of this reaction?
b. How many grams of CO gas are made?
12. If the reaction below proceeds with a 96.8% yield, how many kilograms of calcium sulfate are formed when 5.24 kg of sulfur dioxide reacts with an excess of calcium carbonate and oxygen?
2CaCO3 (s) + 2SO2 (g) + O2 (g) –> 2CaSO4 (s) + 2CO2 (g)
13. For the reaction below there is a 100.0g of each reactant available. Which reagent is the limiting reagent?
2MnO2 + 4KOH + O2 + Cl2 –> 2KMnO4 + 2KCl + 2H2O
14. Explain the term heat of combustion.
15. When carbon disulfide is formed from its elements, heat is absorbed. Calculate the amount of heat (in kJ) absorbed when 5.66 g of carbon disulfide is formed.
C(s) + 2S(s) –>CS2 (l) ΔH = 89.3 kJ
16. The production of iron and carbon dioxide from iron (III) oxide and carbon monoxide is an exothermic reaction. How many kilojoules of heat are produced when 3.40mole of iron (III) oxide reacts with an excess of carbon monoxide?
Fe2O3 (s) + 3CO (g) –> 2Fe (s) + 3CO2 (g) + 26.3kJ
17. When 2 moles of solid magnesium combines with 1 mole of oxygen gas, 2 moles of solid magnesium oxide (MgO) is formed and 1204kJ of heat is released. Write the thermochemical equation for this combustion reaction.
18. Gasohol contains ethanol, C2H5OH (l), which when burned reacts with oxygen to produce carbon dioxide gas and water vapor. How much heat is released when 12.5 g ethanol burns?