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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 precipitate...
JD
Answered by Joshua D. • Chemistry tutor
14546 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. bulkie...
EC
Answered by Edmund C. • Chemistry tutor
2614 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. However a...
AC
Answered by Adam C. • Chemistry tutor
18350 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 greater n...
KN
Answered by Kieran N. • Chemistry tutor
4839 Views

Palladium acts as a heterogeneous catalyst in the reaction between an alkene with hydrogen by providing an alternative reaction route. Describe the stages of this reaction route. (3 marks)

The detail required for many A-level questions is indicated in the number of marks available. As this question awards 3 marks, 3 separate points must be made. For example, the first stage of a heterogeneous ...
AS
Answered by Amy S. • Chemistry tutor
2497 Views