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Chemistry

A Level

What is hybridisation and how can it be used to explain the shapes of molecules?

Before we start on exploring the implications of hybridisation, we should start with a definition. Hybridisation can be thought of as the mixing atomic orbitals into new hybrid orbitals suitable that can ...

Answered by Rebecca M. • Chemistry tutor

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What is the difference between a heterogeneous catalyst and a homogeneous catalyst?

Homogeneous catalyst - catalyst is in the same phase as the reactants. Heterogeneous catalyst - catalyst is in a different phase as the reactants. What ...

Answered by Katie W. • Chemistry tutor

6043 Views

How would you check for halides within a compound and differentiate between them?

Add silver nitrate to the aqueous solution. If a precipitate forms then solution contains halide ions. Chloride: white. Bromide: cream. Iodide: pale yellow. Adding dilute ammonia will dissolve the chlori...

Answered by Artem N. • Chemistry tutor

2076 Views

How do I write the full equation of a cell from two half cells? (basic, with matching electron counts and no water/acid)

Lets use an example:Fe³⁺(aq) + e^- <==> Fe²⁺(aq) E⁰ = +0.771 VLi⁺(aq)+ e^- <==> Li(s) E⁰ = -3...

Answered by Fred P. • Chemistry tutor

1710 Views

Why, in the bromination of phenols, do you not need an acid catalyst like you do in the bromination of benzene?

Benzene's delocalised π electrons means that it is not very nucleophilic and so cannot polarise a neutral molecule and produce the required electrophile. As a result it require a catalyst to form the elec...

Answered by Sian A. • Chemistry tutor

6127 Views