1. A sample gas has a volume of 200cm^3 at 25 degrees celsius and 700mmHg. If the pressure is reduced to 280mmHg, what volume would the gas occupy at the same temperature?

2. A certain noble gas compound contains 68.8% Kr and 31.2% F by mass. Its density at STP is 5.44g/L. What is the molecular formula of the compound?

3A. What volume of CO2 at 1 atm and 225 degrees celsius would be produced by the reaction of 12.0g NaHCO3? 2NaHCO3+H2SO4=Na2SO4+2CO2+H20
(B). On cooling to 20 degrees celsius, what volume would the CO2 occupy?

4. Determine the molar mass of a gas if a sample weighing 0.495g is collected as vapor(gas) in a flask of volume 127cm^3 at 98 degrees celsius. The pressure of the gas vapor at this temperature in the flask was determined to be 754mmHg. Identify the gas.

5. If 10ml of 1.0 M HCL are required to neutralize 50ml of a NaOH solution, how many ml of 1.0 M H2SO4 will neutralize another 50ml of the same NaOH solution?

6. How many liters of ammonia at a pressure of 10 atm and 500 degrees celsius can be produced by the reaction of 6.0g of hydrogen with excess N2? Given 3H2(g) + N2(g)=2NH3(g)

7. When the aqueous solution of Pb(NO3)2 and Na2SO4 are mixed a precipitate of PbSO4 is formed. Calculate the mass of PbSO4 formed when 655ml of 0.150 M Pb(NO3)2 and 525ml of 0.0751 M Na2SO4 are mixed. Given Pb(NO3)2 + Na2SO4= PbSO4 + 2NaNO3.

8. Give half reactions for 2Mg+CO2=2MgO+C and classify the reaction Pb(NO3)2+H2S=PbS+2HNO3