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Chemistry

A Level

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

2230 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

1864 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

6619 Views

Write an ionic equation, with state symbols, to show the reaction of calcium with an excess of water.

Ca(s)+ 2H2O(l) ---> Ca2+(aq) + 2OH– (aq) + H2(g)

Answered by Owais M. • Chemistry tutor

13765 Views

Which chemical would have a higher boiling point 1,3-dimethylbutane or hexane

Hexane would have the higher boiling point, due to the fact it's unbranched unlike 1,3-dimethlybutane, hexane would have more surface contact and hence more London forces acting upon it. As a result it wo...

Answered by Talvin R. • Chemistry tutor

2864 Views