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Chemistry

A Level

In the presence of ultraviolet radiation, cyclohexane reacts with bromine. A mixture of cyclic products are formed, including C6H11Br. Discuss each step of this reaction providing equations to show the mechanism.

INITIATION: Br₂ --> 2Br ^. The breaking of the Br₂ bond from ultraviolet radiation forms two radicals, as one electron from the bond p...

Answered by Lisa K. • Chemistry tutor

17522 Views

State how you would test a solution for the presence of sulfate ions? Explain, using an ionic equation, what you would expect to observe in the presence of sulfate ions.

You would add barium chloride solution to the sample to be tested. Group II sulfate solubility decreases down the group - with barium sulfate being insoluble. We would expect to see a heavy white precipit...

Answered by Joshua D. • Chemistry tutor

12089 Views

give a possible reaction mechanism for the conversion of a haloalkane to alcohol

reaction conditions are reflux (ie with heat) with conc. sodium hydroxide. the mechanism is just a standard Sn1 or Sn2 (uni- or di- molecular nucleophilic substition) depending on the haloalkane used. bul...

Answered by Edmund C. • Chemistry tutor

1884 Views

What is the C-O-H bond angle in propan-2-ol and why is this? [4 marks]

The bond angle is 104.5 degrees. This is because of the pairs of electrons around the oxygen atom: it has 2 bonded pairs and 2 lone pairs. Lone pairs and bonded pairs of electrons repel each other. Howeve...

Answered by Adam C. • Chemistry tutor

15715 Views

Explain how a catalyst can effect the rate of a forward and reverse reaction.

A catalyst can provide a different mechanism or pathway for a chemical reaction through stabalistion of the transition state. The catalyst will lower the activation energy of the reaction meaning a greate...

Answered by Kieran N. • Chemistry tutor

3309 Views