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Chemistry

A Level

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

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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

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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

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In an experiment a burrette was identified as the largest source of uncertainty, how could this uncertainty be reduced?

A burrette is a measuring apparatus a burrette measures the volume of liquid delivered during a titration. with each measurement there is an uncertainty with the recorded measurement of delivered liquid. ...

Answered by Jarrod G. • Chemistry tutor

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Explain the shape carbon tetrachloride

Tetrahedral because there are 4 areas of electron density around the central carbon atom that repel as far away as possible. The bond angle is 109 degrees

Answered by Louis B. • Chemistry tutor

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