Font size
WorksheetsPS Ch 7 Review
Total questions: 54
Worksheet time: 34mins
The substances that undergo change in a chemical reaction are called
(a)
A solution of silver nitrate, AgNO3, is added to a solution of sodium chloride, NaCl. After the reaction is complete, solid AgCl (silver chloride) and NaNO3 (sodium nitrate) remain as precipitates. What are the products of this chemical reaction?
AgNo3 and NaCl
AgNO3 and AgCl
AgCl and NaNO3
NaCl and NaNO3
What does the ARROW in a chemical equation mean?
(a)
Which of the following is a balanced chemical equation for the synthesis of NaBr from Na and Br2?
Na + Br2 --> NaBr
2Na + Br2 --> NaBr
Na + Br2 --> 2NaBr
2Na + Br2 --> 2NaBr
The coefficients in a balanced chemical equation always express the ratio of
moles of reactants and products
volume of reactants and products
atoms of reactants and products
mass of reactants and products
A (a) is the number that appears before a formula in a chemical equation.
A (a) is a representation of a chemical reaction in which the reactants and products are expressed as formulas.
A (a) is an amount of a substance that contains approximately 6.02 x 1023 particles of that substance.
How many atoms are present in 3 moles of silicon?
6.02 x 1023 atoms
1.80 x 1023 atoms
28.086 atoms
3 x (6.02 x 1023) atoms
The molar mass of carbon is (a) g.
How many grams of CO2 are there in 3.2 mol of the compound?
140.8 g
6.02 x 1023 g
13.75 g
38.4 g
The molar mass of NaCl is 58.5 g. A sample of NaCl contains 188g of the compound. The sample contains _____ of NaCl.
3.21 mol
58.5 mol
6.02 x 1023 mol
10998 mol
A + B ---> AB
synthesis
single replacement
decomposition
double replacement
AB ---> A + B
synthesis
single replacement
decomposition
double replacement
A + BC ---> B + AC
synthesis
single replacement
decomposition
double replacement
AB + CD ---> AD + CB
synthesis
single replacement
decomposition
double replacement
A reaction in which a substance reacts rapidly with oxygen, often producing heat and light. Products always include H2O and CO2.
(a)
The process in which an element loses electrons during a chemical reaction is called (a) .
The process in which an element gains electrons during a chemical reaction is called (a) .
Zn + CuCl2 ---> Cu + ZnCl2
synthesis
single replacement
combustion
double replacement
CaO + H2O ---> Ca(OH)2
synthesis
single replacement
combustion
double replacement
2C2H6 + 7O2 ---> 4CO2 + 6H2O
synthesis
single replacement
combustion
double replacement
Energy stored in the chemical bonds of a substance is called (a) energy.
Chemical reactions involve the _____ of chemical bonds in the reactants, and the _____ of chemical bonds in the products.
breaking, formation
formation, breaking
gaining, losing
losing, gaining
Breaking chemical bonds _____ energy.
requires
releases
destroys
creates
The formation of chemical bonds _____ energy.
requires
releases
destroys
creates
A chemical reaction that releases energy to its surroundings is called an (a) reaction.
A chemical reaction that absorbs energy from its surroundings is called an (a) reaction.
2HgO + heat ---> 2Hg + O2
endothermic reaction
exothermic reaction
C3H8 + 5O2 ---> 3CO2 + 4H2O + heat
endothermic reaction
exothermic reaction
Endothermic or exothermic reaction?
endothermic
exothermic
Endothermic or exothermic reaction?
endothermic
exothermic
A (a) is the rate at which reactants change into products over time.
An decrease in temperature will _____ the reaction rate.
increase
decrease
not affect
An increase in surface area will _____ the reaction rate.
increase
decrease
not affect
Stirring the reactants will generally _____ the reaction rate.
increase
decrease
not affect
A (a) is a substance that affects the reaction rate without being used up in the reaction.
Increasing the concentration of a reactant will _____ the reaction.
increase
decrease
not affect
Chemical reactions involve collisions between particles of reactants. If these collisions occur more frequently, then the reaction rate will _____.
increase
decrease
not change
When a catalyst is used in a chemical reaction, the catalyst is written
above the arrow
in the reactants
in the products
in parentheses
When you add baking soda to vinegar, the mixture fizzes as CO2 gas is produced. If you added water to the vinegar before you mixed it with the baking soda, what effect would this have on the rate of CO2 production?
in would increase
it would decrease
it wouldn't change
Which of the following does NOT affect the reaction rate of chemical reactions?
temperature
surface area
stirring
size of container
In a chemical reaction that is at equilibrium, which of the following is true?
All of the reactants have been converted to products.
The reaction stops even though some reactants remain.
Forward and reverse reactions occur at the same rate.
All of the products are gases.
In the chemical reaction shown, how could you shift the equilibrium toward water?
increase the temperature
increase the pressure
decrease the amount of oxygen
add steam to the mixture
A _____ reaction is a reaction in which the conversion of reactants into products and the conversion of products into reactants can happen simultaneously.
reversible
chemical
exothermic
single replacement
During chemical equilibrium, the reactants change into products just as fast as the products change back into reactants.
true
false
When a change is introduced to a system in equilibrium, the equilibrium shifts in the direction that relieves the change.
true
false
According to Le Châtelier’s principle, if you added heat to the system, the equilibrium would shift in the direction that _____heat from the system.
adds
removes
According to Le Châtelier’s principle, if you increased the pressure, the equilibrium would shift in the direction that _____the pressure of the system.
increases
decreases
Le Châtelier’s principle tells you that if you decreased the ammonia concentration by removing ammonia from the system, the equilibrium would shift in the direction that _____ammonia.
removes
produces
The synthesis of ammonia is
endothermic
exothermic
The decomposition of ammonia is
endothermic
exothermic
If we added heat to this system, equilibrium would shift to _____.
remove heat
add heat
If we added heat to this system, equilibrium would shift to _____.
increase the amount of ammonia
decrease the amount of ammonia
