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Name:___________________________
Date:___________________
Semester Exam Practice Problems
1) Convert:
a. 43 miles into meters (1 mile = 5280 ft; 1m = 3.28ft)
b. 165 pounds into kg (1 kg = 2.2 lbs)
c. 130 meters per second into miles per hour
d. 721 lbs per week into kg per second
2) A compound with a molar mass of 284 g/mol contains 43.7% phosphorus and 56.3%
oxygen. What is its molecular formula? What is the name of the compound?
3) What is the mass in grams of 9.35 x 1030 atoms of iron?
4) How many molecules are in a sample of SrCrO4 that has a mass of 24.86 g?
5) How many moles are there when you have 6.047 x 1028 atoms of sodium?
6) Use SigFigs: 349 cm + 1.10 cm + 100 cm = ___________________
7) Use SigFigs:
450 meters / 114 seconds = ___________________
8) How many L are 65mL?
9) Convert 45 hg to kg.
10) Write out the chemical equations for the following reactions:
a. sodium carbonate + calcium chloride yields sodium chloride and calcium
carbonate
b. aluminum nitrate + ammonium hydroxide yields aluminum hydroxide +
ammonium nitrate
11) Determine the mass of lithium hydroxide produced when 0.38 grams of lithium nitride
reacts with water according to the following unbalanced chemical equation:
__Li3N (s) + __H2O (l) → __NH3 (g) + __LiOH (aq)
12) Determine the mass of carbon dioxide produced when 0.85 grams of butane (C4H10)
reacts with oxygen according to the following balanced chemical equation:
2C4H10 (l) + 13O2 (g) → 8CO2 (g) + 10H2O(g)
13) What are the shapes of the s and p orbitals? Draw and example of each.
14) Explain how a zinc atom with a mass of 64 amu can exist, but it doesn’t match the mass
on the Periodic Table.
15) Determine the percent composition of carbon in C12H22O11.
16) Give the name or formula of the following compounds:
a. hexaboron silicide
b. iodine pentafluoride
c. dinitrogen trioxide
d. SeF6
e. Si2Br6
17) Draw the orbital notation for Ca2+.
18) Write the full electron configuration for Mn.
19) In the following equations, identify which species is being oxidized and what is being
reduced?
a. NaI + Br2  NaBr + I2
b. Ag + O2  Ag2O
c. Ni+2 + Sr  Sr+2 + Ni
20) If I do this reaction with 35 grams of C6H10 and 45 grams of oxygen, how many grams of
carbon dioxide will be formed?
2C6H10 +17O212CO2 +10H2O
21) Use this equation: N2 + 3 H2 ---> 2 NH3, for the following problems:
a) If you used 1 mole of N2, how many moles of NH3 could be produced?
b) If 10 moles of NH3 were produced, how many moles of N2 would be
required?
c) If 3.00 moles of H2 were used, how many moles of NH3 would be made?
22) Give the name of the following compounds:
a. SrF2
___________________
b. Na2O
___________________
c. CaS
___________________
d. Cs3N2
___________________
e. MgBr2
___________________
23) Give the formula of the following compounds:
a. beryllium nitride
_____________
b. barium iodide
_____________
c. magnesium fluoride
_____________
d. manganese (IV) sulfide
_____________
e. nickel (I) selenide
_____________
f.
_____________
cobalt (II) chloride
24) Complete the following chart.
Element
Atomic
Number
Atomic
Mass
Iron
26
56
Oxygen
8
16
Protons
Electrons
Charge
Symbol
0
10
Neon
10
Magnesium
Neutrons
12
10
0
11
+2
25) How many protons, neutrons, and electrons are there in a neutral atom of sodium?
P=
N=
E=
26) If you obtained an isotope of the atom described in the previous question, how
would this change the number of protons, neutrons, and electrons?
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27. Assess the accuracy (using % error) and precision (using average deviation) of the
data shown below. D = m/V
Trial
Mass
Volume
1
400.0 g
50.0 mL
2
589.5 g
75.0 mL
3
630.0 g
90.0 mL
Density
Average =
Accepted Value = 7.86 g/mL
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28. Classify each of the following pictures as an element (atomic or molecular),
compound, or mixture.
a. __________________
b. __________________