Chemistry 0620 · IGCSE · The mole and the Avogadro constant

The mole and the Avogadro constant — practice question

On heating lead(II) nitrate, two gases are released and solid lead(II) oxide is left behind. The reaction is represented by the equation below. $2\text{Pb(NO}_3)_2(s) \rightarrow 2\text{PbO}(s) + 4\text{NO}_2(g) + \text{O}_2(g)$
(a)[1]

Calculate the $M_r$ for lead(II) nitrate.

(b(i))[2]

Calculate the mass of lead(II) oxide produced.

(b(ii))[2]

Calculate the volume of oxygen, $\text{O}_2$, produced at room temperature and pressure (r.t.p.).

(c)[2]

Describe a test for oxygen. test ........ observation ........

(d(i))[1]

What does the term excess mean?

(d(ii))[1]

How would the student know when the lead(II) oxide has become excess?

(d(iii))[1]

Write a chemical equation that represents the reaction.

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