Chemistry Assignment Guruh Worksheet

NI 2

ENGR 1540 Worksheet 20 Chapter 5

1. Hydrogen gas is generated when acids come into contact with certain metals. When excess hydrochloric acid reacts with 2.5 g of Zn (the metal product is Zn2+), what volume of hydrogen gas is collected at a pressure of 0.93 atm and a temperature of 22℃?

2. If you need 400.0 mL of hydrogen gas to conduct an experiment at 20.5℃ and 748 torr, how many grams of Zn should be reacted with excess HCl to obtain this much gas?

3. The first step in processing zinc metal from its ore, ZnS, is to react it with O2 according to the reaction 2ZnS(s)+3O2(g)→2ZnO(s)+2SO2(g) If 620 kg of ZnS is to be reacted, what volume of oxygen at 0.977 atm and 34℃ is needed (at a minimum) to carry out this reaction?

4. What volume of oxygen at 24℃ and 0.88 atm is needed to completely react via combustion with 45 g of methane gas?

5. If boron hydride, B4H10, is treated with pure oxygen, it burns to give B2O3 and H2O: 2B4H10(s)+11O2(g)→4B2O3(s)+10H2O(g) If a 0.050-g sample of the boron hydride burns completely in O2, what will be the pressure of the gaseous water in a 4.25-L flask at 30.0℃?

6. N2O5 is an unstable gas that decomposes according to the following reaction: 2N2O5(g)→4NO2(g)+O2(g) What would be the total pressure of gases present if a 10.0-L container at 22.0℃ begins with 0.400 atm of N2O5 and the gas completely decomposes?

7. Ammonia is not the only possible fertilizer. Others include urea, which can be produced by the reaction, CO2(g)+2NH3(g)→CO(NH2)2(s)+H2O(g). A scientist has 75 g of dry ice to provide the carbon dioxide. If 4.50 L of ammonia at 15℃ and a pressure of 1.4 atm is added, which reactant is limiting? What mass of urea will form?

8. Consider the following reaction: 6NiO(s)+4ClF3(g)→6NiF2(s)+2Cl2(g)+3O2(g) What mass of NiO will react with a sample of ClF3 gas that has a pressure of 250 torr in a 2.5-L flask at 20℃?

9. What volume of hydrogen gas, in liters, is produced by the reaction of 3.43 g of iron metal with 40.0 mL of 2.43 M HCl? The gas is collected at 2.25 atm of pressure and 23℃. The other product is FeCl2.

10. Magnesium will burn in air to form both Mg3N2 and MgO. What mass of each product would be found if burning a 3.11-g sample of magnesium to completion produces a combined total of 5.09 g of the two products?