Download Chemistry Review: Unit2 - Menno Simons Christian School

Name: ___________________________
Date:____________________________
Chemistry Review: Unit2
Topic 1:
1) List 5 pieces of safety equipment you feel are necessary for a sage school science laboratory.
i. _________________________________________________
ii. _________________________________________________
iii. __________________________________________________
iv. __________________________________________________
v. __________________________________________________
2) Use particle theory to explain what a pure substance is.
All particles in the substance are identical
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3) Use particle theory to explain what a solution is.
Contains at least two different types of particles: the solvent particles(more numerous) and the solute
particles (less numerous) which are evenly mixed.
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4) Use particle theory to explain what a mechanical mixture is.
Two or more types of particles that are not evenly mixed.
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5) Give an example of the following solutions:
i.
Gas dissolved in a gas: _____________air__________________________
ii.
Gas dissolved in a liquid:
iii.
___________carbonated beverage________________
Liquid dissolved in a liquid: _________radiator fluid_____________________
Topic 2:
6) Name 5 observations that indicate a chemical change.
Heat is produced or absorbed, starting material is used up, there is a change in colour, a material with
new properties is formed, gas bubbles form in a liquid, a precipitate forms in a liquid and the change is
difficult to reverse.
7) In the table below list whether there is a chemical or physical change and how you know.
Observation
Sugar dissolves
in water.
Filament of a
light bulb glows
when an electric
current flows
through it.
A watermelon is
crushed with a
hammer.
Physical Change
or
Chemical Change
Physical
Sugar can be returned to a solid form by boiling away the water
Physical
Same looks the same before the switch is turned on as off
Physical
Particles is re-arranged
How do you know? (Hint: Look at your list for #6)
Topic 3:
8) What is the difference between “The Law of Conservation of Mass” and “The Law of Definite
Composition”
Conservation of mass deals with balancing the mass in a chemical reaction, whereas the law of definite
composition deals with the combining ratios in a compound and not chemical changes.
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9) According to Dalton, what is the difference between an element and a compound?
An element cannot be broken down into simpler substances by means of a chemical change whereas a
compound can be.
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10) True or False: Is a theory based on observation?
Circle your answer: T or F
_because a theory is an educated guess based on observations.
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Explain why:
Topic 4:
11) Fill in the following table with the chemical families have we learned about in this unit and their respective
charges.
Family
Alkali metal
Alkali Earth Metal
Halogen
Noble Gases
Charge (example: +2, +1, 0, -1, -2)
+1
+2
-1
0
12) What are “Coinage Metals”?
Metals that are used to make coins (money)
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13) What are the three physical properties of Coinage Metals?
iii.
_______________________
Do not readily combine with oxygen.__________________________
Are malleable_____________________________________
iv.
Conductive
i.
ii.
Unreactive with most acids _____________
Topic 5:
14) What purposes might modern scientist use the periodic table for?
Make predictions about new chemical reactions or new elements and to discover which elements have
similar properties.
Properties
Element
Name
15) Choose 3 of the first 18 elements and fill in the following table with 4 properties for each element.
Topic 6:
16) What is an ion?
_an ion is a particle or group of particles with a positive or negetive charge.
17) What is a molecule?
_a molecule is the smallest independent unit of a pure substance and is generally a cluster of atoms joined
together ie)diatomic molecule. _
18)
What is a diatomic molecule?
_a molecule made up of two atoms of the same element.
What is the difference between a molecule and diatomic molecule?
Diatomic molecules have to be made up of the same element whereas molecules do not.
Topic 7:
19) Express the following chemical reaction in words:
Na + Cl  NaCl
Sodium + chlorine  sodium chloride
20) Express the following chemical reaction using a formula:
Methane burning in oxygen producing carbon dioxide and water.
CH4 + 2 O2  CO2 +2 H2O + Energy
Topic 8:
21) List 5 ways you could increase the rate of a chemical reaction.
Increase temperature, increase surface area, increase the concentration of a product & adding a catalyst
22) What is the difference between:
i.
Reactant & Product:
Reactants are the substances that are combined in a chemical reaction whereas the products are the new
substances creased by the reaction.
ii.
___________________________________
Catalyst and Inhibitor:
_both change the rate of reaction but catalysts speed it up while inhibitors slow it down.
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iii.
Chemical reaction and rate of reaction:
_chemical reaction is one in which a chemical change takes place and new substances are formed whereas
the rate of a reaction is the speed at which the reaction occurs
23) Write down a word equation for corrosion.
Iron + oxygen = iron oxide
24) List 3 harmful effects of burning fossil fuels.
Toxic compounds, global warming, acid rain etc.
25) Is the following reaction exothermic or endothermic?
2C2H2 + 5O2  4 CO2 + 2 H2O + Energy
i.
ii.
_exothermic_____________________________________________
_____
How do you know that it is endothermic or exothermic?
__because exothermic reactions produce energy and energy is one of the product on the right hand side of
the equation.
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27. Label the following chemical compounds as ionic or molecular then identify their chemical name.
Chemical
______Ionic/Molecular_______
_________Chemical Name___________
a. O2
molecular
dioxide
b. H2O
molecular
dihydrogen monoxide
c. KCl
ionic
potassium chloride
d. HBr
molecular
hydrogen bromide
e. SeO2
molecular
selenium dioxide
f. BF3
molecular
boron trifloride
g. LiF
ionic
lithium flouride
h. NO
molecular
nitrogen monooxide
i.
K3 N
ionic
potassium nitride
j.
Na2O
ionic
sodium oxide
k. CO
molecular
carbon monoxide
l.
ionic
calcium oxide
CaO