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What is the difference between and exothermic and endothermic reaction and how can you tell the difference?

An exothermic reaction is a reaction which transfers enerygy to its surroudings.And endothermic reaction is one that absorbs energy from its surroundings.An exothermic reaction will make its environment w...

Answered by Kawthar H. • Chemistry tutor

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Explain what is meant by dynamic equilibrium. (2)

The forward reaction and the backward reaction occur at the same time (1) and at the same rate (1).

Answered by Nancy M. • Chemistry tutor

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Draw a dot and cross diagram of a Chlorine molecule showing the outer electrons only.

Chlorine has seven outer electrons. Electrons like to be in pairs. In one Chlorine atom, there are three pairs and one lonely electron which doesn't have a pair. (draw). So two Chlorine atoms form a Chlor...

Answered by Lisa M. • Chemistry tutor

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Write a word equation for the reaction between marble chips and hydrochloric acid. (1) How could the rate of reaction be increased and why? (7)

i) Marble chips are made from calcium carbonate.Hydrochloric acid + calcium carbonate -> Calcium chloride + water + carbon dioxideii) The rate of reaction can be increased by increasing the concentrati...

Answered by Michelle K. • Chemistry tutor

31245 Views

How can you work out, using the changes in oxidation numbers, which compound out of KCl, KBr and KI has the greatest reducing power?

We can work this out by observing the changes in oxidation state of sulphur in concentrated sulphuric acid (H₂SO₄) when this compound reacts with KCl, KBr and KI individually.
A...

Answered by Sarah P. • Chemistry tutor

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