Chemistry Reference
In-Depth Information
CH
4
+ 2O
2
2H
2
O + CO
2
x g
3.00 g
# of moles of CO
2
=
mass of sample
3.00 g
44.0 g/mole
=
= 0.0682 moles
molar mass
Mass of water = # of moles × molar mass = 0.136 moles × 18.0 g/mole = 2.45 g
So, 2.45 g of H
2
O are produced as 3.00 g of CO
2
are generated from
the combustion of methane.
Now, complete the practice problems, and then move on to Lesson 7-5.
Lesson 7-4 Review
Use the following balanced chemical equation to answer questions 1-3:
2Mg
(s)
+ O
2(g)
2MgO
(s)
magnesium + oxygen
magnesium oxide
1.
How many grams of magnesium would be required to produce 2.50 g
of magnesium oxide?
2.
How many grams of oxygen would be required to react completely
with 1.18 g of magnesium?
3.
How many grams of magnesium oxide can be formed if 0.875 g of
magnesium react with an excess of oxygen?
Use the following balance chemical equation to answer questions 4-6:
2KClO
3
KCl + 3O
2
potassium chlorate
potassium chloride + oxygen
4.
How many grams of potassium chloride can be produced from the
decomposition of 5.00 g of potassium chlorate?
5.
How many grams of potassium chlorate are required to produce 3.00 g
of oxygen?
6.
How many grams of oxygen are produced from enough potassium
chlorate to produce 4.00 g of potassium chloride?
Complete all of the required steps to answer the following questions:
7.
How many grams of water can be produced from the complete
combustion of 255 g of methane gas?
8.
How many grams of water can be produced from the complete
combustion of 255 g of propane gas?
