At stp how many liters of oxygen are required to react completely with 4.5 liters of hydrogen to form water? 2h2(g)+o2(g)—> 2h2o(g)
1.8 l
3.0 l
9.0 l
2.0 l

how many moles of aluminum are needed to react completely with 4.9 mol of feo? 2al(s)+3feo(s)—> 3fe(s)*al2o3(s)
4.9 mol of al
0.8 mol of al
3.3 mol of al
7.4 mol of al

you are required to use the molar mass in all of the following stoichiometric calculations except
volume-volume problems
mass-mass problems
mass-particle problems
mass-volume problems

iron(lll) oxide is formed when iron combines with oxygen in the air. how many grams of fe203 are formed when 23.7 g of fe reacts completely with oxygen? 4fe(s)+3o2(g)—> 2fe2o3(s)
33.9
23.9
135
71.1

what is the mole ratio of d to b in the generic chemical reaction? 2a+b-> c+3d
1: 1
2: 1
3: 2
3: 1

how many grams of co are needed to react with an excess of fe203 to produce 108.5 g fe? fe2o3(s)+3co(g)-> 3co2(g)+2fe(s)
157.8
81.6
36.3
325.5

solid sodium reacts violently with water, producing heat, hydrogen gas, and sodium hydroxide. how many molecules of hydrogen gas are formed when 57.1 g of sodium are added to water? 2na+2h2o-> 2naoh+h2
2.4999
1.51*10^24
6.37*10^23
7.48*10^23

the masses of the reactants and the theoretical yield of the products for a chemical reaction are shown below. when this reaction was performed in the laboratory, the actual yield for sbl3 was 2.4 g. what was the percent yield for sbl3? 3sb(1.2g) + 3i2(2.4g) -> 2sbi3(3.2g) + sb(0.4g)
25%
67%
75%
100%

which conversion factor do you use first to calculate the number of grams of co2 produced by the reaction of 50.6 g o2 with excess ch4? the equation for the complete combustion of methane is
ch4(g) + 2o2(g) -> co2(g) + 2h2o(l)
44.0 g co2/2 mol co2
1 mol o2/32.0 g o2
2 mol o2/1 mol co2
1 mol ch4/16.0 g ch4

explain the significance of coefficients in a balanced chemical reaction.