Chemistry 5070 · O Level · The mole and the Avogadro constant

The mole and the Avogadro constant — practice question

Potassium chlorate, KClO$_3$, breaks down to give potassium chloride and oxygen. 2KClO$_3$(s) $\rightarrow$ 2KCl(s) + 3O$_2$(g)
(a)[2]

Calculate the percentage by mass of oxygen in potassium chlorate.

(b)[3]

Calculate the maximum volume of oxygen formed at room temperature and pressure when 12.25 g of potassium chlorate is completely decomposed.

(c(i))[3]

Explain in terms of gain and loss of electrons, how potassium ions and chloride ions are formed when potassium reacts with chlorine.

(c(ii))[2]

Predict two physical properties of potassium chloride.

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