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Chemical formulae, equations and calculations

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Question 35

Potassium chlorate(V) ( $KClO3\text{KClO}_3$ ) decomposes when heated to form potassium chloride ( $KCl\text{KCl}$ ) and oxygen ( $O2\text{O}_2$ ), as shown by the balanced chemical equation:

2\text{KClO}_3\text{(s)} \rightarrow 2\text{KCl(s)} + 3\text{O}_{2}\text{(g)}

A 4.90 g sample of potassium chlorate(V) ( $M_r = 122.5$ ) is completely decomposed.

Calculate the mass, in grams, of potassium chloride ( $M_r = 74.5$ ) formed.

[3]

Markscheme

Chemical formulae, equations and calculations Questions

IGCSE
Chemistry
Chemical formulae, equations and calculations

80 exam-style questions on Edexcel IGCSE Chemistry Chemical formulae, equations and calculations. Each one has a worked solution and a mark scheme showing where the marks go.

Chemical formulae, equations and calculations

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Chemical formulae, equations and calculations

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Question 35

Potassium chlorate(V) ( $KClO3\text{KClO}_3$ ) decomposes when heated to form potassium chloride ( $KCl\text{KCl}$ ) and oxygen ( $O2\text{O}_2$ ), as shown by the balanced chemical equation:

2\text{KClO}_3\text{(s)} \rightarrow 2\text{KCl(s)} + 3\text{O}_{2}\text{(g)}

A 4.90 g sample of potassium chlorate(V) ( $M_r = 122.5$ ) is completely decomposed.

Calculate the mass, in grams, of potassium chloride ( $M_r = 74.5$ ) formed.

[3]

Markscheme

Chemical formulae, equations and calculations Questions

IGCSE
Chemistry
Chemical formulae, equations and calculations

80 exam-style questions on Edexcel IGCSE Chemistry Chemical formulae, equations and calculations. Each one has a worked solution and a mark scheme showing where the marks go.