MYP 5 Chemistry Practice

Which of the following is the best definition for a mole in chemistry?

• A unit that measures the mass of an element

• A measure of the volume of a gas at standard temperature and pressure.

• A unit that represents the concentration of a solution.

• A unit that represents the number of molecules of a substance

Which of the following is the best definition for molarity in chemistry?

• The mass per liter

• The total volume of a solution divided by the number of particles

• The concentration of a solution measured in grams per liter

• The concentration of a solution measured in moles per liter (number of molecules per liter)

For the reaction A+3B --> 2C

How does the rate of disappearance of B compare to the rate of production of C?

• The rate of disappearance of B is 1/2 the rate of appearance of C

• The rate of disappearance of B is 3/2 the rate of appearance of C

• The rate of disappearance of B is 2/3 the rate of appearance of C

• The rate of disappearance of B is 1/3 the rate of appearance of C

For the reaction A+3B --> 4C +5D

the rate of reaction in terms of ΔA would be written as...

• -ΔA/Δt

• +0.5(^ΔA/_Δt)

• -0.5(^ΔA/_Δt)

• -2(^ΔA/_Δt)

For the reaction A+3B --> 4C +5D

the rate of reaction of B in terms of ΔA would be written as...

• -ΔA/Δt

• +0.5(^ΔA/_Δt)

• 3(^ΔA/_Δt)

• -2(^ΔA/_Δt)

In the combustion of methane, CH₄(g) + 2O₂(g) --> CO₂(g) + 2H₂O(g)

Which reactant has the greatest rate of disappearance?

• CH₄

• O₂

• H₂O

• O₂ and H₂O have the same rate of disappearance

Which is NOT a possible graph of concentration versus time for a REACTANT?

• a

• b

• c

• d

Assuming that each of the following graphs has the same concentration and time axes, which has the greatest rate of disappearance of reactant?

• a

• b

• c

• d

• a

• b

• c

• d

In the graph above which graph could represent a product?

• dashed

• gray

• black

• None of them