Mr. Storie
20S Science
Chemistry Review
Chemistry Unit Review
ANSWER KEY
1. What color does litmus paper turn in
a. stays/turns red
b. stays/turns blue
2. The number of protons in an atom can be determined from the ________________.
atomic number on the periodic table.
3. How many of each type of atom is in the compound dinitrogen pentoxide?
two nitrogen, 5 oxygen
4.
Write the formula for the above compound
N2O5
5. Ionic compounds form between __________ and ______________.
metal and non-metal.
6. Covalent compounds from between two ______________.
non-metals.
7. Define the following terms:
a. Period is a row of the periodic table where all elements have the same valence shell number.
b. family is the column of the table that has elements arranged into similar properties.
8. Name 5 families on the periodic table.
 Alkali metals
 Alkaline earth metals
 Chalcogens
 Halogens
 Noble gases
9. Which of the above families does not react?
Noble gases.
10. Give an example for each of the following reaction types:
a. Addition (synthesis)
Na + Cl2  NaCl
b. Decomposition
KI  K + I2
c. Single replacement
Mg + CaO  MgO + Ca
d. Double replacement
LiF + CsI  LiI + CsF
e. Combustion
CH4 + O2  H2O + CO2
11. Name 4 characteristics for acids and 4 characteristics for bases
Mr. Storie
20S Science
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Chemistry Review
sour
corrosive
release gas (hydrogen) when reacted with metals
contains hydrogen
bitter
corrosive
usually contains hydroxide ion
neutralizes acids
12. The element lithium has an atomic number of 3 and a mass number of 7. How many neutrons does it have?
Mass # = #p + #n; 4 neutrons
13. How many electrons are in the outer orbit of rubidium (atomic number 37, atomic mass 85), a member of the
alkali metals?
1; all members of the alkali family have 1 electron in the outer shell.
14. What is a chemical family?
a group of elements located in a vertical column on the periodic table which share similar
characteristics, including # of electrons in the outer shell.
15. How are ionic compounds formed? What subatomic particle is involved?
Ionic compounds are formed between metals and nonmetals, electrons are transferred from one
element to the other and the resulting +/- charge holds then together.
16. How do covalent compounds form?
The sharing of electrons between atoms.
17. What is the charge on calcium when it forms an ion?
+2
18. What information does the combining capacity of an element provide?
The number of electrons the atom would like to donate or accept to become stable (full outer shell).
19. What is the charge that results when a halogen forms an ion?
-1
20. What are the characteristics of acids?
sour taste, turn litmus paper red, phenolphthalein clear, conducts electricity (some) when dissolved in
water, (aspirin, vinegar, coke).
21. How do you carry out a neutralization reaction? (what do you mix)
mix an acid and base to get salt and water.
22. What family is the most unreactive. Why?
Noble gases, outer shell (valance) is full and does not want to donate or accept any electrons.
23. Which chemical bonds are the result of electron transfer?
Ionic bonds.
Mr. Storie
20S Science
Chemistry Review
24. When sodium and chlorine react together to produce sodium chloride, what type of reaction is occurring?
Na + Cl2  NaCl ; is a synthesis reaction.
25. Which of the following is a correctly balanced chemical equation?
a. H2 + O2  H2O
b. H2 + 2 O2  H2O2
c. H2 + O2  2 H2O
d. 2 H2 + O2  2 H2O
26. What is an endothermic reaction?
A reaction that requires that energy (heat) he added (on the reactants side) for the reaction to proceed
(baking).
27. What is the general form of a single replacement reaction?
Z + AB  ZB + A
28. When performing a chemistry lab for Mr. Storie, you mix two solutions together. You observe that the
beaker containing the solutions felt hot to the touch. What kind of a reaction is this?
Exothermic (heat is given off as a product).
29. What is the general form of a double replacement reaction?
AB + ZY  AY + ZB
30. You add aluminum to a blue solution of CuCl2 , after some evidence that a chemical reaction has occurred,
you notice a reddy-brown solid forming on the bottom of the beaker. What is this brown substance? What
kind of a reaction is this?
Copper (Cu); single replacement reaction.
31. What happens in a chemical reaction?
atoms are rearranged.
32. What kind of information is provided by a chemical equation?
elements present, and in what proportions, what happens when these substances are mixed.
33. Match the following terms:
__F_
__H_
_I__
_D__
_C__
_A__
_G__
_E_ 8.
1. Ion
2. Atom
3. Electron
4. Proton
5. Ionic bond
6. Covalent bond
7. Isotopes
Endothermic reaction
a. results from electron sharing
b. a reaction that gives of heat
c. the attraction between positive and negative ions
d. a positively charged particle
e. a reaction that absorbs energy
f. an atom/group with a charge on it
g. a negatively charged particle
h. the smallest particle of an element that exists by itself
i. atoms of the same element with different masses
j. a neutral particle
Mr. Storie
20S Science
Chemistry Review
34. Use the following information to answer the following questions: Mr. Storie spends his free time trying to
find new elements. Recently she discoved a new element called Storium – its symbol is St. The only Thing
we know about this new element is that it is an alkali metal.
Write the formula when it combines with the following:
a. Iodine:
StI
b. Sulphur:
St2S
c. Carbonate (polyatomic – look through your notes)
St2CO3
35. The following are covalent compounds. Write the formula for the following element pairs:
a. dinitrogen trioxide –
N2O3
b. carbon tetrachloride –
CCl4
36. Name the following covalent compounds:
a. CF4
carbon tetrafluoride
b. P2O3
diphosphorus trioxide
37. Write the products of the following reaction:
Acid + base 
salt + water
38. Balance the following equations. Leave the space blank or add a “1” if no coefficient is required.
a.
2 HgO  2 Hg + 1 O2
b.
3 Fe +
4 H2O 
1 Fe3O4 + 4 H2
c.
2 Pb3O4  6 PbO +
1 O2
39. Name all of the above compounds in each reaction:
a. decomposition
b. single replacement
c. decomposition
40. How many sulfur atoms are in disulphur trioxide?
2
41. What is a mass number?
#p + #n
42. What is a period?
horizontal row of periodic table
43. What are diatomic molecules? What elements does this apply to?
elements that never exist in nature alone (often found bonded to self); I H N Br O Cl F.
Mr. Storie
20S Science
Chemistry Review
44. List the characteristics of a base. Give some examples?
Tastes bitter; turns phenolphthalein pink, turns litmus blue; corrosive; draino, windex, oven cleaner
45. What is phenolphthalein? What does it do?
a substance the indicates whether an unknown is an acid or base by changing colour when mixed with
either. Turns pink in presence of base, clear in acid.
46. Name the following ionic compounds:
a. NaCl Sodium chloride
b. BeCl2 Beryllium chloride
c. Fe2O3 Iron (III) oxide
47. Write formulas for the following ionic compounds:
a. Potassium iodide PI
b. Silver nitrate AgNO3
c. Gold (II) oxide AuO
48. What is combustion? What are the products?
Oxygen reacts with another substance (usually a carbon compound) to product heat and light, water
and carbon dioxide gas.
49. What is a cation? How is it different from an anion?
Cations are positively charged particles, anions have a negative charge.