levo

Periodicity and Group Chemistry

Halogens as Oxidising Agents and Displacement Reactions

  • 3 things to know
  • Papers 1 and 3

Overview

Oxidising power decreasing down the group, and the colour changes in a displacement reaction.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

What is the trend in oxidising ability of the halogens as you descend Group 7?

Key term

Why does oxidising ability decrease down Group 7?

Key term

What type of reaction occurs when a more reactive halogen is added to a solution containing a less reactive halide ion?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    What is the trend in oxidising ability of the halogens as you descend Group 7?

    Model answer

    Oxidising ability decreases down Group 7.

  2. 2

    Why does oxidising ability decrease down Group 7?

    Model answer

    As atomic radius increases down the group, the ability to attract and gain electrons decreases because the outer shell is further from the nucleus and there is greater shielding.

  3. 3

    What type of reaction occurs when a more reactive halogen is added to a solution containing a less reactive halide ion?

    Model answer

    A displacement reaction occurs.

  4. 4

    What is observed when chlorine water is added to potassium bromide solution?

    Model answer

    The solution turns orange/brown as bromine is formed.

  5. 5

    What is observed when chlorine water is added to potassium iodide solution?

    Model answer

    The solution turns brown/black as iodine is formed.

  6. 6

    What is observed when bromine water is added to potassium iodide solution?

    Model answer

    The solution turns brown/black as iodine is formed.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.

1Closed book
2Open book
3Closed book

The 3-step method, run for you

Answer cold, learn it, then prove it stuck. Levo tracks the jump between your first attempt and your last.

Atomic Structure
Amount of Substance
Bonding
Energetics and Thermodynamics

Cram a whole paper in one sitting

Sort every topic into what you know and what you do not, then drill only the weak ones.

A atom.
nitrogencarbonsulfur

Blank Blitz makes facts automatic

Rapid timed gap-fills on the terms and numbers you need to recall without thinking.

AOxidation is the loss of electrons.
BReduction is the gain of electrons.
CAn oxidising agent is an electron acceptor.

Build It gets the exam shape right

Assemble a full-mark answer from its marking points, in the order an examiner wants them.

The sum of all mole fractions equals 1.
TrueFalse

Test It catches misconceptions

Spot the fault in a statement. The traps are the mistakes students actually make.

721941163128510

Brain Breaks between sessions

Short focus games to reset attention, so the next set lands better than the last.

Every question in Periodicity and Group Chemistry, on a schedule.

Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.

Or £46 a year, about £3.83 a month. Cancel anytime.