GENERAL CHEMISTRY
Calculations Based on Equations
Sheet No. 1
1.
Calculate the molecular weight of the following compounds.
a.
2.
3.
4.
KClO3
6.
7.
H2NaPO4
a.
8 g of O3
b. 1 g of hydrogen
c.
30.65 g KClO3
d. 8 g of oxygen
Calculate the number of grams in each of the following cases.
a.
.1 mole of oxygen
b. .02 moles of H2SO4
c.
1 x 10-1 mole of HCl
d. 1 x 10-3 moles of hydrogen
How many atoms are there in the
32g of oxygen
b. .1 mole of oxygen
c. .355 g of chlorine
A.
3.1 moles of a compound weigh 52.7 g. Calculate the molecular weight of the compound.
B.
A .02 mole sample of a compound weights 0.6 g. Calculate the molecular weight of the
compound.
A.
How many grams of oxygen are there in 120 g of CuO?
B.
Calculate the percent of oxygen in CuO.
C.
Calculate the percent of Cu in CuO.
A.
Calculate the percent of C in CO2.
B.
How many g of oxygen react with 6 g of C to form CO2 according to:
C + O2
8.
c.
Calculate the number of moles in each of the following cases.
a.
5.
b. O3
CO2
C.
Calculate the weight of CO2 formed from 2 g of C reacting with an excess of oxygen.
A.
How many grams of NaCl are formed from 5 g of NaOH reacting with an excess of HCl
according to
NaOH + HCl
B.
NaCl + H2O
How many moles of NaCl are formed in (A)?
9.
C.
How many moles of H2O are formed in (A)?
D.
How many grams of H2O are formed in (A)?
3 grams of hydrogen and 17 g of nitrogen are allowed to react to form NH3 according to
N 2 + H2
10.
NH3
A.
Which of the two substances is in excess?
B.
How many grams of NH3 are formed in (A)?
Oxygen reacts with C4H8 to give CO2 and H2O. Calculate:
A.
How many moles of oxygen combine with 0.5 moles of C4H8?
B.
How many moles of C4H8 combine with 15 moles of oxygen?
C.
How many g of CO2 are formed from 96 g of oxygen in excess of C4H8?
D.
How many moles of CO2 are formed in (C)?
ANSWERS
Calculations based on Equations
Sheet No. 1
1.
a.
122.6 g/mole
b. 48 g/mole
c.120 g/mole
2.
a.
.17 moles
b. .5 moles
c. .25 moles
d. .25 moles
3.
a.
3.2 g
b. 1.96 g
c. 3.65 g
d. .002 g
4.
a.
2 x 6.02 x 1023
b. 1.204 x 1023
c.
6.02 x 1021
5.
a.
17
b. 30
6.
a.
24.2
b. 20.1%
c.
79.9%
7.
a.
27.3%
b. 16
c.
7.3 g
8.
a.
7.3 (g)
b. .13 moles
c. .13 moles
d. 2.25 g
9.
a.
N2 is in excess by 3 g
b. 17 g of NH3
10.
a.
3 moles
b. 2.5 moles
c. 88 g
d. 2 moles