Malavika had it all set for a chemical change to take place. She took Potassium Chlorate on a petri dish and kept it outside exposed to the air on the table for two hours. She knew that potassium placed highest on the reactivity chart will breakdown into its constituent elements when exposed to the atmosphere. However, that did not happen. Can you explain the reason why? [3 MARKS]

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Solution

Reason out: 1.5 Marks
Explanation: 1.5 Marks

We know that Potassium being most reactive is placed highest in the reactivity chart. However when in the form of a compound, for a decomposition reaction to happen it is a must that this reactant is heated to undergo a chemical change i.e.
Potassium Chlorate upon heating decomposes to produce two new products, Potassium Chloride and Oxygen. Since Malavika did not heat the reactant, she could not obtain the desired products.

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