Name____ANSWER KEY_______________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the
question.
1) What is the empirical formula for C4H10O2?
1) __C__
A) CHO
B) CH2O
2) Write the formula for strontium nitride.
2) __E__
A) Sr(NO3)2
B) SrN
C) C2H5O
D) C2H4O
E) CHO2
C) Sr(NO2)2
D) Sr2N3
E) Sr3N2
3) Write a balanced equation to show the reaction of sulfurous acid with lithium hydroxide to form
water
and lithium sulfite.
H2SO3 + 2 LiOH
→
Li2SO3
+ 2 HOH
4) What is the mass (in kg) of 6.89 × 1025 molecules of CO2? The molar mass of CO2 is 44.01 g/mol.
4) __A__
A) 5.04 kg
B) 6.39 kg
C) 3.03 kg
D) 2.60 kg
E) 3.85 kg
5) Determine the volume of hexane that contains 5.33 × 1022 molecules of hexane.
The density of hexane is 0.6548 g/mL and its molar mass is 86.17 g/mol.
5) __C__
A) 8.59 mL
B) 7.40 mL
C) 11.7 mL
D) 13.5 mL
E) 12.4 mL
6) How many molecules of HCl are formed when 50.0 g of water reacts according to the
following balanced reaction? Assume excess ICl3.
2 ICl3 + 3 H2O → ICl + HIO3 + 5 HCl
6) __D__ A) 6.09 × 1025 molecules HCl
B) 3.65 × 1024 molecules HCl
D) 2.78 × 1024 molecules HCl
E) 5.02 × 1025 molecules HCl
C) 1.67 × 1024 molecules HCl
7) What volume of 0.305 M AgNO3 is required to react exactly with 155.0 mL of 0.274 M Na 2SO4
solution?
Hint: you will want to write a balanced reaction.
7) __B__
A) 173 mL
B) 278 mL
C) 139 mL
D) 345 mL
E) 581 mL
*8) According to the following reaction, what amount of Al 2S3 remains when 20.00 g of Al2S3 and 2.00 g
of H2O are reacted? A few of the molar masses are as follows: Al 2S3 = 150.17 g/mol, H2O = 18.02
g/mol.
* this problem has been CORRECTED from what was on the sheet handed out originally.
Al2S3(s) + 6 H2O(l) → 2 Al(OH)3(s) + 3 H2S(g)
8) __C_
A) 19.78 g
B) 28.33 g
C) 11.67 g
D) 14.00 g
E) 8.33 g
9) Determine the theoretical yield of HCl if 60.0 g of BCl3 and 37.5 g of H2O are reacted according to the
following
balanced reaction. A possibly useful molar mass is BCl3 = 117.16 g/mol.
BCl3(g) + 3 H2O(l) → H3BO3(s) + 3 HCl(g)
9) __C__
A) 75.9 g HCl
B) 25.3 g HCl
C) 56.0 g HCl
D) 132 g HCl
E) 187 g HCl
10) How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following
reaction?
The molar mass of KNO3 is 101.11 g/mol.
10) __A__
mol O2
4 KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)
A) 0.724 mol O2
B) 23.2 mol O2
C) 1.73 mol O2
D) 0.580 mol O2
E) 18.5