Unit 9 - Stoichiometry Part 2 Review

In the ideal gas law, _____ represents moles of gas

• P

• V

• R

• n

Determine the Kelvin temperature required for 0.0470 mol of gas to fill a balloon to 1.20 L under .998 atm pressure.

• 0 K

• 107 K

• 207 K

• 307 K

In an exothermic reaction

• The reactants store more energy than the products

• The products store more energy than the reactants

• The kinetic energy of the system decreases

• ∆H for the reaction is positive

What do we call the chemical present in the largest quantity in a solution?

• Electrolyte

• Solute

• Solvent

• Tincture

What is the molarity of a solution prepared from 10.0 g of NaCl and 255 mL of water?

• 0.04 M

• 0.0007 M

• 0.67 M

• 0.23 M

In the lab you find four bags; each contains 5.00 g of a different gas at STP. The gases are O2, CH4, CO2, and Ne. Rank the bags in order of increasing volume.

• CO2, O2, Ne, CH4

• CO2, Ne, O2, CH4

• CH4, O2, CO2, Ne

• Ne, CH4, CO2, O2

When potassium chlorate, KClO3 is decomposed, oxygen gas and potassium chloride are produced. What volume of oxygen gas at STP is produced when 4.72 g of KClO3 decomposes? Molar Volume = 22.4 L/mol

• 0.04 moles

• 1.29 Liters

• 4.72 Liters

• 105.78 L

New concept cars in the Detroit Auto Show feature engines that burn hydrogen gas in air to produce water vapor. Suppose that fuel tank contains 150. L of H2 gas at 20.0 atm pressure at 25 ˚C. How many moles of H2 gas is present when the tank is full?

• 1.2 moles

• 6.7 moles

• 14.4 moles

• 15.0 moles

Why does a bottle of soda "fizz" when it is first opened?

• The sudden release of pressure upon opening reduces the solubility of carbon dioxide in the soda, causing the carbon dioxide to come out of solution.

• The soda companies insert a microchip into the bottom of the can that releases a gas when the bottle is first opened to tell you that it is fresh.

• The shaking of the bottle from transport causes the fizzing.

• None of the Above

To convert mL to L, one should:

• Divide by 1000

• Divide by 100

• Multiply by 1000

• Multiply by 100