Incorrect paper 1

Question 1

Answer 1

C

The correct answer is C: Br⁻(aq) can reduce Cl₂(aq) because:

1. Understanding Oxidising and Reducing Agents
   
   • A reducing agent donates electrons and gets oxidised.
   • An oxidising agent accepts electrons and gets reduced.
   • Halogens (X₂) act as oxidising agents, while halide ions (X⁻) act as reducing agents.
2. Oxidising Strength of Halogens (X₂)
   
   • F₂ > Cl₂ > Br₂ > I₂ (fluorine is the strongest oxidising agent).
   • This means Cl₂ is strong enough to oxidise Br⁻ into Br₂ but not the other way around.
3. Reducing Strength of Halide Ions (X⁻)
   
   • I⁻ > Br⁻ > Cl⁻ > F⁻ (iodide is the best reducing agent).
   • This means Br⁻ can reduce Cl₂ to Cl⁻ because Cl₂ is a stronger oxidising agent.
4. Why is C Correct?
   
   • Br⁻ donates electrons to Cl₂, reducing Cl₂ to Cl⁻.
   • Br⁻ itself gets oxidised to Br₂.

Equation:

This matches option C, making it the correct answer.

Question 2

Answer 2

A

Question 3

Answer 3

A

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

B

Question 7

Answer 7

Since Na+ is smaller than K+, the distance between Na+ and O2- is shorter, leading to a stronger attraction and a more exothermic lattice enthalpy.
- Rember atoms and ions aren’t the same thing so you can’t talk about atomic radius ion context of an ion.
- And we know that in this context we are looking at ions as the question states lattice enthalpy which is : The enthalpy change when **one mole of ionic compound is formed from gauseous ions under standard states and conditions. Remember IONS IONS IONS !!!

Question 8

Answer 8

Question 9

Answer 9

Question 10

Answer 10

C

Question 11

Answer 11

C

Question 12

Answer 12

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

Question 16

Calculate the bond enthalpy of the F–F bond.

Answer 16

Or use hess law