In need of help setting up each of these problems.

Under the conditions in a laboratory experiment, 0.0513 grams of aluminum (At. Wt.=27.0) was reacted with excess hydrochloric acid to produce hydrogen gas according to the following balanced equation:
2 Al+ 6 HCL -> 2 AlCl3+ 3 H2

A) Determine the number of moles of H2 evolved from the quantity of aluminum when collected over water.

B) If the Volume of gas generated was 75.0 mL and the temperature was 27.0 degrees celsius, determine the total pressure of the hydrogen gas evolved from the quantity of aluminum stated above.

C) The vapor pressure of water at 27.0 degrees celsius was 26.7 mmHg, determine the partial pressure of the hydrogen gas collected in mmHg.

1 answer

A.
mols Al = grams/atomic mass = ? This is n in part B.

B.
Use PV = nRT. You know n, R, V and T. Remember V is in L, T in kelvin, R=0.08205. Solve for P in atm.

C.
Ptotal = pH2 + pH2O. Ptotal and pH2O are given. Solve for pH2.