Page 29 - Curriculum Visions Dynamic Book
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exothermic reaction: a reaction that gives heat to the surroundings. Many oxidation reactions, for example, give out heat.
noble metal: silver, gold, platinum, and mercury. These
are the least reactive metals.
oxidising agent: a substance that removes electrons from another substance (and therefore is itself reduced).
When a solution of yellow potassium chromate is dropped into a colourless solution of mercuric nitrate, an orange precipitate of mercuric chromate forms.
When water is added,
the mercuric nitrate is dissolved. As the reaction is completed,
a colourless solution of mercuric nitrate remains.
(Notice that there was an excess of mercury used in this demonstration, which remains unchanged at the bottom of the beaker.)
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