A-Level Chemistry Fundamentals 2

Question 1

Which statement about the reaction between sodium and water is correct?

Accepted Answer

Sodium floats, melts into a ball, and produces hydrogen gas and sodium hydroxide

Answer

Sodium sinks and reacts slowly to produce sodium oxide

Answer

Sodium reacts violently producing sodium chloride and oxygen

Answer

Sodium dissolves without any gas being produced

Question 2

What type of reaction mechanism does the hydrolysis of a primary halogenoalkane with aqueous NaOH follow?

Accepted Answer

SN2 (nucleophilic substitution, bimolecular)

Answer

SN1 (nucleophilic substitution, unimolecular)

Answer

Electrophilic addition

Answer

Free radical substitution

Question 3

Le Chatelier's principle predicts that increasing the pressure of a gaseous equilibrium will favour which side?

Accepted Answer

The side with fewer moles of gas

Answer

The side with more moles of gas

Answer

The exothermic direction

Answer

Neither side — pressure has no effect on equilibrium

Question 4

What is the enthalpy change for the reaction if 50 cm³ of 1.0 mol dm⁻³ HCl reacts with 50 cm³ of 1.0 mol dm⁻³ NaOH, raising the temperature by 6.8°C? (Assume c = 4.18 J g⁻¹ K⁻¹, density = 1 g cm⁻³)

Accepted Answer

-56.8 kJ mol⁻¹

Answer

-2.84 kJ mol⁻¹

Answer

+56.8 kJ mol⁻¹

Answer

-28.4 kJ mol⁻¹

Question 5

In mass spectrometry, what does the peak with the highest m/z value in the spectrum of a compound typically represent?

Accepted Answer

The molecular ion (M⁺)

Answer

The base peak

Answer

The most stable fragment

Answer

A doubly charged ion

Question 6

Which of the following is the correct order of increasing boiling points?

Accepted Answer

CH₄ < NH₃ < H₂O

Answer

NH₃ < CH₄ < H₂O

Answer

H₂O < NH₃ < CH₄

Answer

CH₄ < H₂O < NH₃