SCH4U - Review Problem Set
The following questions are a sample of the type of questions that you should be able to answer after
completing the SCH3U course.
1. Complete and balance the following chemical equations. Identify the type of reaction.
a) Li + H2O 
b) Pb(NO3)2 + NaCl 
c) Na2CO3 + HCl 
2. Without using a calculator, perform the following arithmetic.
a) (1.0 X 107) X (4.0 X 105)
c) (5.0 X 10-4) X (2.0 X 10-6)
(2.0 X 108)
(1 X 10-12)
4
-5
10
b) (4.0 X 10 ) X (6.0 X 10 )
(3.0 X 10-2)
5
d) (3.0 X 10 ) + (2.1 X 10 )
e) (8.0 X 1012)/(2.0 X 10-3)2
3. In what region of the periodic table are the largest atoms found? Where are the smallest atoms found?
4. How are isotopes of the same element alike? How do they differ?
5. Calculate the formula weight or molecular mass of each substance.
a) Sodium chloride, NaCl
b) Sucrose (table sugar), C12H22O11
c) Calcium propionate, Ca(C3H5O2)2, a food additive
d) Ferrous ammonium sulphate, (NH4)2Fe(SO4)2
6. How many moles of sulphur atoms must be combined with 2.0 mol of iron atoms to give iron pyrite,
FeS2?
7. Sodium bicarbonate, NaHCO3, is one ingredient of baking powder. In one experiment in a series of
tests of different ratios of ingredients, a scientist used 21.0 g NaHCO3. How many moles of NaHCO3
were in this sample?
8. Balance the following equations:
a) Al2O3 + H2SO4  Al2(SO4)3 + H2O
b) KHCO3 + H3PO4  K2HPO4 + H2O + CO2
c) C9H20 + O2  CO2 + H2O
9. Lactic acid, the substance that causes sour milk to taste as it does, has a formula weight of 74 g/mol. It
consists of 48.63% C and 8.18% H, with the rest being oxygen. Calculate the empirical and molecular
formulas of lactic acid, arranging the atomic symbols in alphabetical order.
10. Analysis shows a hydrocarbon to be composed of 80% C and 20% H.
a) What is its simplest formula?
b) Its density is 1.34 g/L at STP. What is its molecular mass?
c) What is its molecular formula?
11. Asbestos, a known cancer-causing agent, has a typical formula, Ca3Mg5(Si4O11)2(OH)2. How many atoms
of each element are given in this formula?
12. a) Write the formulas and names of the elements that exist in nature as molecules that are composed
of 2 atoms.
b) Where are they found on the periodic table?
13. If a steel cylinder with a volume of 1.50 L contains 10.0 mol of oxygen, under what pressure (in atm) is
the oxygen if the temperature is 27.0C?
14. A gas measuring 525 mL is collected at 104.66 kPa. What volume does this gas occupy at 99.33 kPa?
15. A gas occupies 50.0 mL at standard temperature. What volume will it occupy at 335C if pressure
remains unchanged?
16. Does the label "0.500 M NaCl" tell how much solution is in the bottle?
17. Calculate the number of grams of each solute that has to be used to make each of the following
solutions.
a) 250 mL of 0.100 M NaCl
b) 100 mL of 0.440 M C6H12O6 (glucose)
c) 500 mL of 0.500 M H2SO4
18. Give the chemical formula for the combination of the following (if there is more than one possible
answer, list them all:
a) Zinc and Phosphate
d) Mercury and Oxygen
b) Sodium and Nitrite
e) Iron and oxygen
c) Tin and bromine
f)
Copper and chlorine
19. Calculate the mass percentage composition of each compound.
a) MgCl2
d) C7H5N3O6
b) Na2SO4
e) AlBr3 · 6H2O (percent of water)
c) Fe2O3
20. A sample of iron ore weighing 2.80 g is to be analyzed for the percentage of iron. All of the iron in the
sample is converted into iron oxide (Fe2O3) which has a mass of 1.00 g. What is the percentage of iron
in the ore?
21. What is the relationship between first ionization energies and atomic radius of an atom?
22. A clinical thermometer registers a patient's temperature to be 37.13C. What is this temperature in K?
23. The coldest permanently inhabited place on the Earth is the Siberian village of Oymyakon in Russia. In
1964 the temperature reached a shivering -69.12C! What is this temperature in K?
24. Helium has the lowest boiling point of any liquid. It boils at 4 K. What is its boiling point in C?
25. Calculate the number of grams of sodium peroxide, Na2O2, that would be required to produce 50 g of
oxygen by the following reaction; 2 Na2O2 + 2 H2O  4 NaOH + O2
26. How many litres of pure O2 at STP, are required to react completely with 2.43 g of magnesium?
27. Magnesium metal reacts quantitatively with oxygen to give magnesium oxide, MgO. If 5.00 g of Mg
and 5.00 g of O2 are allowed to react, what weight of MgO is formed, and what is the mass of excess
reactant?
28. Give the chemical names for the following:
a) NaClO3
g) NH4NO3
b) HCl (aq)
h) Ni3(PO4)2
c) HCl (g)
i) CuSO4 · 5H2O
d) Ca(CN)2
j) N2O4
e) H3PO4
k) NaC2H3O2
f) NaOH
l) NH3 (common and IUPAC name)
29. State the rules for naming binary acids and oxyacids.
30. Predict whether the following reactions will go to completion.
the equation, if not write N/R for no reaction.
a) Al (s) + Ca(NO3)2(aq) 
b) Cl2 (g) + CaBr2 (aq) 
c) Sn (s) + FeSO4(aq) 
d) I2 (s) + NaCl (aq) 
e) K (s) + Na2CO3 (aq) 
If they do, give products and balance
31. Predict the products of the following reactions and identify the precipitate using solubility rules.
a) Sodium carbonate and hydrobromic acid
b) Phosphoric acid and lithium hydroxide
c) Ammonium chloride and magnesium hydroxide
d) Lead(II) nitrate and silver sulfate
e) Copper(II) hydroxide and phosphoric acid
32. Draw the Lewis Structures for the following compounds.
Show dipoles on the polar bonds.
NH3
CaCl2
H2O
CO2
Fe2(SO4)3
CuCl2
33. Calculate the molar concentration when 4.6g of NaCl is dissolved to make a 250.0mL solution.
34. You need 100.0mL of a 0.8M solution of NaOH. You find a stock solution of 1.2M NaOH. Calculate,
and explain how you will make the solution.
35. In the diagrams, illustrate how NaCl and C6H12O6 behave when they are dissolved in water.
NaCl (aq)
C6H12O6 (aq)
36. On the periodic table provided, indicate the different categories of elements.
a) Colour the six metalloids green
b) Colour the metals blue
c) Colour the non-metals yellow
37. Draw arrows that show the increasing trend for atomic radius, first ionization energy and
electronegativity.