IB Chemistry SL - Round 2

When an aqueous solution of sulfuric acid is added to an aqueous solution of potassium hydroxide the temperature increases. Which describes the reaction taking place?

• Exothermic, sign of ΔH +

• Exothermic, sign of ΔH −

• Endothermic, sign of ΔH +

• Endothermic, sign of ΔH −

Which is an appropriate unit for the rate of a reaction?

• mol dm^-3 s

• mol dm^-3 s^-1

• mol dm^-3

• s

What is the best definition of rate of reaction?

• The time it takes to use up all the reactants

• The rate at which all the reactants are used up

• The increase in concentration of a product per unit time

• The time it takes for one of the reactants to be used up

What is the pH of 1.0 x 10^-4 mol dm^-3 sulfuric acid?

• −4

• between 3 and 4

• 4

• between 4 and 5

The value of K_c for the reaction between hydrogen and bromine in the gas phase to produce hydrogen bromide is 4.0 x 10^-2. What is the value of K_c for dissociation of gaseous hydrogen bromide into hydrogen and bromine?

• 4.0 x 10^-2

• 2.0 x 10^-2

• 25

• 400

Which of the following is not a conjugate acid-base pair?

• HNO₃ / NO₃⁻

• H₂SO₄ / HSO₄⁻

• NH₃ / NH₂⁻

• H₃O⁺ / OH⁻

What is the IUPAC name for C(CH₃)₃CH₂CH₃?

• 2-methyl-2-ethylpropane

• hexane

• 2,2-dimethylbutane

• 2-methylpentane

The reaction between bromine and ethene in the dark is an example of:

• free radical substitution

• esterification

• nucleophilic substitution

• addition

Which compound is an ester?

• CH₃COOH

• CH₃OCH₃

• C₂H₅CHO

• HCOOCH₃

The mass spectrum of a compound shows peaks with m/z values of 88, 73, 59 and 43. Which compound could give this spectrum?

• HCOCH₂CH₂CH₃

• CH₃CH₂COOCH₂CH₃

• CH(CH₃)₂COOH

• CH₃CH₂CH₂COOH