Posted by Jao on .
A gaseous mixture containing 4.15 mol of hydrogen gas and 7.13 mol of oxygen gas reacts to form steam
(a) Write the balanced equation for the reaction.
(b) What is the limiting reactant?
(c) What is the theoretical yiels of steam in moles?
(d) How many moles of the excess reactant remain unreacted?

Chemistry 
MathMate,
1. equation
Start with the equation:
2H2+O2 = 2H2O
Since both H2 and O2 are in gaseous forms, the coefficients are in proportion to the volume of the gases.
2. limiting reactant
since the ratio of the volumes of hydrogen and oxygen is 4.15/7.13=0.58 (as opposed to 2/1=2 in the equation), can you determine which gas is the limiting reactant?
3. theoretical yield:
4.15 mol of H2 will react with 2.075 mol of O2. Determine the theoretical yield from the equation in (1).
4. Excess reactant
is what is not being used.
Post your answers for checking if you wish.