E-LITE AS level Chemistry Quiz Series 4

The isotopes of magnesium, ²⁴Mg and ²⁵Mg, both form ions with charge 2+. Which of

the following statements about these ions is true?

• Both ions have electronic configuration 1s² 2s² 2p⁶ 3s²

• 
• The ions have the same number of electrons but different numbers of neutrons.

• The ions have the same number of neutrons but different numbers of protons.

. Which equation represents the reaction for which the enthalpy change, ΔH, is the mean bond enthalpy of the C–H bond?

• ¼CH₄(g) → ¼C(g) + H(g

• CH₄(g) → C(s) + 2H₂(g)

• CH₄(g) → C(g) + 4H(g)

• CH₄(g) → C(g) + 2H₂(g)

The first ionization energies, in kJ mol–1, of four elements with consecutive atomic numbers are shown below.

A 1680

B 2080

C 496

D 738

Which element could be an inert gas?

• A

• B

• C

• D

The graph above shows the second ionization energy of a series of elements with consecutive atomic numbers.

Which element could be lithium?

• A

• B

• C

• D

Going down Group 1 from lithium to rubidium

• the radius of the atom decreases.

• the radius of the ion decreases.

• the first ionization energy decreases.

• the polarizing power of the ion increases.

What is the name of this compound?

• ethanol

• ethanal

• ethanone

• methanal

Which compound is a structural isomer of Z-but-2-ene?

• butane

• E-but-2-ene

• cyclobutane

• methylbut-2-ene

Which equation is a propagation step in the conversion of trichloromethane into tetrachloromethane by reaction with chlorine in the presence of ultraviolet light?

• CHCl₃ + Cl₂ ⟶ CCl₄ + HCl

• ●CCl₃ + ●Cl ⟶ CCl₄

• CHCl₃ + ●Cl ⟶ CCl₄ + ●H

• ●CCl₃ + Cl₂ ⟶ CCl₄ + ●Cl

How many structural isomers are there with the molecular formula C₃H₆BrCl?

• 4

• 5

• 6

• 7

How many different alkenes are formed when 2-bromo-3-methylbutane reacts with ethanolic potassium hydroxide?

• 2

• 3

• 4

• 5