levo

Halogenoalkanes, Alcohols and Organic Analysis

Test-Tube Reactions for Functional Groups

  • 3 things to know
  • Papers 2 and 3

Overview

The reagents and observations that identify alkenes, alcohols, aldehydes and carboxylic acids.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

What reagent is used to test for the presence of an alkene functional group?

Key term

What observation indicates a positive test for unsaturation when testing with bromine?

Key term

What colour change occurs when bromine water is added to an alkene?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    What reagent is used to test for the presence of an alkene functional group?

    Model answer

    Bromine or bromine water

  2. 2

    What observation indicates a positive test for unsaturation when testing with bromine?

    Model answer

    Decolourisation of the bromine (orange/brown colour disappears)

  3. 3

    What colour change occurs when bromine water is added to an alkene?

    Model answer

    Orange/brown to colourless

  4. 4

    What reagent can be used to distinguish between an aldehyde and a ketone?

    Model answer

    Fehling's solution

  5. 5

    What observation indicates a positive test when Fehling's solution reacts with an aldehyde?

    Model answer

    Blue solution produces a brick-red precipitate

  6. 6

    What observation indicates a positive test when Tollens' reagent reacts with an aldehyde?

    Model answer

    Colourless solution produces a silver mirror

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 Halogenoalkanes, Alcohols and Organic Analysis, 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.