# Extra Problems.

## Presentation on theme: "Extra Problems."— Presentation transcript:

Extra Problems

Because of increasing evidence of damage to the ozone layer, chlorofluorocarbon (CFC) production was banned in However, there are about 100 million auto air conditioners that stiss use CFC-12 (CF2Cl2). These air conditioners are recharged from stockpiled supplies of CFC-12. Continued

If each of the 100 million automobiles contains 1
If each of the 100 million automobiles contains 1.1 kg of CFC-12 and leaks 25% of its CFC-12 into the atmosphere per year, how much Cl in kilograms is added to the atmosphere each year due to auto airconditioners? (Assume two significant figures for all calculations.)

A pure copper cube has an edge length of 1. 42 cm
A pure copper cube has an edge length of 1.42 cm. How many copper atoms does it contain (volume of a cube = (edge length)3, density of copper = 8.96 g/cm3.

Fingernail-polish remover is primarily acetone (C3H6O)
Fingernail-polish remover is primarily acetone (C3H6O). How many carbon atoms are in a bottle of acetone with a volume of 325 mL? (density of acetone = g/mL)

Lakes that have been acidified by acid rain (HNO3 and H2SO4) can be neutralized by a process called liming, in which limestone (CaCO3) is added to the acidified water. Write ionic and net ionic equations to show haw limestone reacts with nitric acid and sulfuric acid to neutralize them. How would you be able to tell if the neutralization process was working?

What solution can you add to each of the following cation mixtures to precipitate one cation while keeping the other ion in solution? Fe+2 + Pb+2  K+ + Ca+2  Ag+ + Ba+2  Cu+2 + Hg2+2  Sr+2 + Hg2+2  NH4+ + Ca+2 

A solution contains one or more of the following ions: Ag+, Ca+2, and Cu+2. When sodium chloride is added to the solution, no precipitate occurs. When sodium sulfate is added to the solution, a white precipitate occurs. The precipitate is filtered off and sodium carbonate is added to the remaining solution, producing a precipitate. Which ions were present in the original solution? Write net ionic equations for the formation of each of the precipitates observed.

A solution contains one or more of the following ions: Hg22+, Ba+2, and Fe+2. When potassium chloride is added to the solution, a precipitate forms. The precipitate is filtered off and sodium sulfate is added to the remaining solution, producing no precipitate. When potassium carbonate is added to the remaining solution, a precipitate occurs. Which ions were present in the original solution? Write net ionic equations for the formation of each of the precipitates observed.