WorksheetsChemistry Sem. 2 Midterm Review
Total questions: 60
Worksheet time: 3hrs 10mins
Name
Class
Date
1.
The best definition for a mole provided below is
a)
The SI unit for the mass of something
b)
The SI unit for the amount of a substance
c)
The SI unit for the volume of something
d)
The SI unit for the area of a substance
2.
The number 6.02 x 1023, which is the number of particles found in a mole.
a)
molar mass
b)
mole
c)
Avogadro's number
d)
hydrate
3.
What is the molar mass of copper?
a)
12 g/mol
b)
63.5 g/mol
c)
58.9 g/mol
d)
40.1 g/mol
4.
What is the molar mass of table salt (NaCl)?
a)
116.9 g/mol
b)
35.5 g/mol
c)
23 g/mol
d)
58.4 g/mol
5.
What is the molar mass of B2(CO3)3?
a)
81.6 g/mol
b)
94.8 g/mol
c)
38.8 g/mol
d)
201.6 g/mol
6.
How many moles are in 3.01 x 1022 atoms of magnesium?
a)
0.05 moles
b)
1.81 x 1046 moles
c)
5.00 x 1021 moles
d)
5.00 moles
7.
The mass in grams of one mole of any pure substance.
a)
molecular formula
b)
hydrate
c)
mole
d)
molar mass
8.
How many grams are there is 1.35 x 1025 atoms of K2SO4?
a)
3,909 g K2SO4
b)
174.1g K2SO4
c)
3.53 x 1021 g K2SO4
d)
423 g K2SO4
9.
How many grams are in 1.2 x 1024 molecules of CO?
a)
28 grams
b)
56 grams
c)
6.02 grams
d)
1.2 grams
10.
How many water molecules are in 5.2 moles of water?
a)
6.02 x 1023
b)
5.2
c)
3.1304 x 1024
d)
8.638 x 10-24
11.
What are the units for molar mass?
a)
grams
b)
amu
c)
grams/mole
d)
liters
12.
2H2 + O2 → 2H2O
How many moles of water can be produced if 8 moles H2 are used?
How many moles of water can be produced if 8 moles H2 are used?
a)
4 moles
b)
8 moles
c)
16 moles
d)
2 moles
13.
In the reaction 2 H2 + O2 → 2 H2O what is the mole ratio of oxygen to water
a)
1:2
b)
2:1
c)
3:4
d)
4:3
14.
In the equation 6 CO2 + 6 H2O → C6H12O6 + 6 O2, the mole ratio of water to oxygen is:
a)
6:6
b)
1:6
c)
6:1
15.
2H2 + O2 → 2H2O
How many moles of oxygen are consumed if 4 moles H2 are used?
How many moles of oxygen are consumed if 4 moles H2 are used?
a)
2
b)
4
c)
6
d)
8
16.
How many particles are in 13.5 grams of Beryllium?
a)
1.5 particles
b)
9 particles
c)
4x1023 particles
d)
9x1023 particles
17.
How many moles are in 98.3 g of Aluminum Hydroxide (Al(OH)3)?
a)
2.14 mol
b)
1.26 mol
c)
6.63 mol
d)
5.9 mol
18.
How many grams are in 3.3 mol of Potassium Sulfide (K2S)?
a)
360 g
b)
454 g
c)
238 g
d)
132 g
19.
How many grams are in 1.2 x 1024 molecules of CO?
a)
28 grams
b)
56 grams
c)
6.02 grams
d)
1.2 grams
20.
What is the mass of 2.50 mol of oxygen gas O2?
a)
40 g
b)
80 g
c)
16 g
d)
32 g
21.
How many moles of methane (CH4) are in 1.24 x 1023 molecules of methane?
a)
6.02 x 1023
b)
7.46 x 1046
c)
978
d)
0.206
22.
How many Nitrogen Atoms are in one mole of Calcium Nitrate Ca(NO3)2 ?
a)
6.02 x 1023
b)
1.204 x 1024
c)
2
d)
3.01 x 1023
23.
8.3 moles H2 makes how many moles of H2O?
2H2 (_____) + O2 (_____) −−〉 2H2O (_____)
a)
4.15
b)
8.3
c)
16.6
d)
74.04
24.
2H2 + O2 −−〉 2H2O
3.91 g O2 −−〉g H2O
3.91 g O2 −−〉g H2O
a)
1.905
b)
4.4
c)
2.2
d)
1.1
25.
How many grams are in one mole of Oxygen
a)
16
b)
32
c)
15.99
d)
31.98
26.
Find the percent yield
2Fe2O3 + 3C −−〉 4Fe + 3CO2
38.1 g Fe2O3 −−〉 Fe
9.53 g C −−〉 Fe
Actual yield = 17.41
2Fe2O3 + 3C −−〉 4Fe + 3CO2
38.1 g Fe2O3 −−〉 Fe
9.53 g C −−〉 Fe
Actual yield = 17.41
a)
65.3
b)
29.4
c)
26.65
d)
59.14
27.
How many steps does a grams to grams problem have?
a)
1
b)
2
c)
3
d)
4
28.
If you start with 3.88 x 1024 atoms of Na and an excess of Cl2, how many grams of NaCl should you get?
2Na + Cl2 −−〉 2NaCl
2Na + Cl2 −−〉 2NaCl
a)
376.66
b)
6.45
c)
753.31
d)
188.33
29.
2Al + 3H2SO4 -> Al2(SO4)3 + 3H2
How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?
How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?
a)
0.85 g
b)
290 g
c)
450 g
d)
870 g
30.
4 Al + 3 O2 –> 2 Al2O3 How much aluminum would be needed to completely react with 45 grams of O2?
a)
1.05 moles
b)
3.75 moles
c)
1.875 grams
d)
1.875 moles
31.
In a lab, a scientist calculate he should produce 12.3 grams of product in his experiment. When he is finished collecting his product it weighs 10.1 grams. What is his percent yield?
a)
82%
b)
0.82%
c)
10.1 %
d)
100%
32.
How many particles are in 13.5 grams of Beryllium?
a)
1.5 particles
b)
9 particles
c)
4x1023 particles
d)
9x1023 particles
33.
What is the empirical formula for the following molecular formula: C6H14
a)
C6H14
b)
C3H7
c)
CH2
d)
CH3
34.
What is the molecular formula if the empirical formula is CH2O and the molecular molar mass is 180.18?
a)
CH2O
b)
C2H4O2
c)
C4H8O4
d)
C6H12O6
35.
Whats the empirical formula of a molecule containing 18.7% of Lithium, 16.3% of Carbon and 65.0% of oxygen?
a)
CO2Li3
b)
Li2CO3
c)
Li3CO2
d)
LiCO5
36.
What is the molecular formula if the empirical formula is C2H5 and the molecular molar mass is 58.14 g/mol?
a)
C2H5
b)
C4H10
c)
C1H2.5
d)
C4H8
37.
How many grams are in 2.25 moles of propane, C3H8.
a)
99 g
b)
16.0 g
c)
0.051 g
d)
96.0 g
38.
Find the percent composition of N2S2.
a)
N: 69.6% S: 30.4%
b)
N:36% S: 75.6%
c)
N: 96.6% S: 3.4%
d)
N: 30.4% S: 69.6%
39.
What is the molecular formula of a compound with an empirical formula of C2OH4 and a molar mass of 88 grams per mole?
a)
C2O4H8
b)
C8O2H4
c)
C4O2H8
d)
C4O8H2
40.
What is the empirical formula for the following molecular formula: C5H12
a)
C5H12
b)
CH3
c)
CH2
d)
C2.5H6
41.
How many moles of gas are contained in 890.0 mL at 21.0 °C and 750.0 mm Hg pressure?
a)
.0364
b)
.00474
c)
.5096
d)
.0684
42.
Determine the Kelvin temperature required for 0.0470 mol of gas to fill a balloon to 1.20 L under .998 atm pressure.
a)
0 K
b)
107 K
c)
207 K
d)
307 K
43.
If the pressure exerted by a gas at 25 degrees C in a volume of 0.044 L is 3.81 atm, how many moles of gas are present?
a)
.002766 mole
b)
.0069 mol
c)
2.766 mol
d)
9.887 mol
44.
Calculate the volume that a 0.323-mol sample of a gas will occupy at 265 K and a pressure of 0.900 atm.
a)
7.18 L
b)
7.81 L
c)
4.63 L
d)
4.36 L
45.
A gas at a volume of 4 liters is at a pressure of 2 atm. The volume is changed to 16 Liters, what must the new pressure be?
a)
2 atm
b)
12 atm
c)
10 atm
d)
0.5 atm
46.
A nitrogen gas has a volume of 600mL at a pressure of 1atm. What volume will the gas occupy at a pressure of 3atm, assuming the temperature remains constant?
a)
125mL
b)
300mL
c)
200mL
d)
400mL
47.
There are 65 liters of helium in a balloon at 35 K. If the temperature of the balloon is increased to 40 K, what will the new volume of the balloon be?
a)
40 L
b)
70 L
c)
74.3 L
d)
75.9 L
48.
There are 40 liters of helium in a balloon at 100 K. If the temperature of the balloon is increased to 200 K, what will the new volume of the balloon be?
a)
80 L
b)
45 L
c)
54 L
d)
45.33 L
49.
5 atm = ________ kPa
a)
506.5 kPa
b)
505 kPa
c)
456 kPa
d)
598 kPa
50.
2.35 atm = ___________ mmHg
a)
1675 mmHg
b)
1786 mmHg
c)
5476 mmHg
d)
2.35 mmHg
51.
A sample of neon gas has a volume of 0.00043 L at 24*C. At what temperature in degrees Celsius sill it have at a volume of 0.00057 L?
a)
224 k
b)
-48.9*C
c)
394 K
d)
121 *C
52.
A gas has a pressure of 1.50 atm at a temperature of 273 K. What will be the pressure at 410 K?
a)
.99 atm
b)
2.25 atm
c)
.75 atm
d)
2.5 atm
53.
Convert 0* C to Kelvin
a)
-273 K
b)
273 K
c)
0 K
d)
100 K
54.
I have 130 Liters of gas in a piston at a temperature of 250 * C. If I cool the gas until the volume decreases to 85 Liters, what will the temperature of the gas be?
a)
799 *C
b)
527 K
c)
335 K
d)
69 *C
55.
A sample of Argon gas occupies a volume of 1.8 L at 2.8 atm. What will its volume be at 1.2 atm?
a)
.77 L
b)
1.87 L
c)
3.0 L
d)
4.2 L
56.
What is 50 C in Kelvin?
a)
223
b)
323
c)
100
d)
50
57.
What will happen to the volume of a gas under constant temperature if the pressure increases?
a)
Increase
b)
Decrease
c)
Nothing
d)
Explosion!
58.
If you increase the pressure of a constant volume of gas, what will happen to the temperature?
a)
Increase
b)
Decrease
c)
Stay the same
d)
It will Blow Up
59.
You have a gas that has a pressure of 2 ATM and a volume of 10L. What would be the new volume if the pressure was changed to 1 ATM?
a)
5 L
b)
20 L
c)
It would stay at 10L
d)
1 L
60.
If a balloon is cooled what will happen to the volume?
a)
Volume will increase
b)
Volume will decrease
c)
Volume will not change
100 %
