WorksheetsUnit 9 Practice
Total questions: 22
Worksheet time: 22mins
Name
Class
Date
1.
In the reaction
2Ca(s) + O2(g) --> 2CaO(s), calcium is __________
2Ca(s) + O2(g) --> 2CaO(s), calcium is __________
a)
Reduced
b)
Synthesized
c)
Oxidized
d)
None of the above
2.
Which of the following elements does NOT have an oxidation number of +2?
a)
Ca
b)
Sr
c)
K
d)
Ba
3.
What element always has an oxidation number of -1?
a)
Hydrogen
b)
Fluorine
c)
Chlorine
d)
Iodine
4.
What is the oxidation number of Fe in FeO?
a)
+1
b)
-1
c)
+2
d)
-2
5.
Is calcium oxidized or reduced in the following reaction?
2CaO--> 2Ca + O2
2CaO--> 2Ca + O2
a)
Oxidized
b)
Reduced
6.
Which does not occur in oxidation?
a)
loss of oxygen
b)
loss of hydrogen
c)
loss of electrons
d)
increase in oxidation number
7.
Define 'Enthalpy'
a)
a) Energy stored in the movement of molecules in a substance
b)
b) The opposite of temperature
c)
c) The temperature of a molecule
d)
d) Energy stored in the chemical bonds in a substance
8.
What is meant by the Law of Conservation of Energy'?
a)
a) Energy lost can not be conserved
b)
b) Energy can neither be destroyed or created
c)
c) Temperature at start of reaction = Temperature at end of reaction
d)
d) Energy = Mass of products - Mass of Reactants
9.
Which statement is true regarding exothermic reactions?
a)
a) Temperature change is positive and enthalpy change is positive
b)
b) Temperature change is positive and enthalpy change is negative
c)
c) Temperature change is negative and enthalpy change is positive
d)
d) Temperature change is negative and enthalpy change is negative
10.
Energy in exothermic reactions are
a)
released
b)
absorbed
11.
Endothermic reactions feel
a)
warm
b)
cold
12.
Calculate the enthalpy of reaction (ΔH) and state whether each reaction is exothermic or endothermic
4CO2 (g) + 6H2O (g) → 2C2H6 (g) + 7O2 (g)
4CO2 (g) + 6H2O (g) → 2C2H6 (g) + 7O2 (g)
a)
550.647 KJ/mol
b)
2855.584 KJ/mol
c)
-550.647 KJ/mol
d)
-2855.584 KJ/mol
13.
Calculate the enthalpy of reaction (ΔH) and state whether each reaction is exothermic or endothermic.
2H2S (g) + SO2 (g) → 3S (s) + 2H2O (l)
2H2S (g) + SO2 (g) → 3S (s) + 2H2O (l)
a)
233.57 JK/mol
b)
31.63 JK/mol
c)
-31.63 JK/mol
d)
-233.57 JK/mol
14.
What type of reaction is shown in the reaction pathway?
a)
endothermic reaction
b)
exothermic reaction
15.
Specific heat capacity is
a)
heat energy needed to raise temp by 1C
b)
heat energy needed to raise temp of 1g of substance by 1C
c)
heat energy absorb to raise 1g of substance to higher temp
d)
heat energy need to raise temp for 1g of substance
16.
How do you calculate Enthalpy of a reaction?
a)
ΔH = ΔHproducts - ΔHreactants
b)
ΔT = q / mC
c)
ΔG = ΔH -TΔS
d)
E = mc2
17.
What is standard enthalpy of formation, ΔHfo?
a)
Heat change when 1 mole of gaseous ions is hydrated in water at 25oC and 1 atm
b)
Heat change when 1 mole of compound is formed from its elements in their standard states at 25oC and 1 atm
c)
Heat change when 1 mole of gaseous atom is formed from its elements at 25oC and 1 atm
d)
Heat change when 1 mole of electrons is removed from 1 mole of gaseous atoms at ground state at 25oC and 1 atm
18.
Finding Nemo was a story of a father trying to find his son. The sequel came out and it was titled
a)
Finding Nemo again
b)
Finding Merlin
c)
Finding Water
d)
Finding Dory
19.
How many days are there in a leap year?
a)
365
b)
356
c)
366
d)
29
20.
What is this note?
a)
C
b)
G
c)
D
21.
Which label on the diagram accurately identifies the Activation energy for an exothermic reaction?
a)
A
b)
B
c)
C
d)
D
22.
What is the value of
ΔH for the reaction represented in the graph?
ΔH for the reaction represented in the graph?
a)
20 kJ
b)
-20 kJ
c)
60 kJ
d)
-60 kJ
100 %
