When 6.00 g of an impure sample of reacts completely with excess hydrochloric acid at…

CHEMISTRY · Single correct · A Level · Chemistry · Amount of substance · Amount of substance

Problem

When 6.00 g of an impure sample of

\text{Mg}

reacts completely with excess hydrochloric acid at 298 K and 1.00 atm, 2.24 L of

\text{H}_2

gas is collected.

\text{Mg}(\text{s})+2\,\text{HCl}(\text{aq})\rightarrow\text{MgCl}_2(\text{aq})+\text{H}_2(\text{g})

Which pair of values best represents (i) the mass of pure

\text{Mg}

present in the sample and (ii) the percent purity of the sample? (a)

4.86\,\text{g}

and

81.0\%

(b)

2.23\,\text{g}

and

37.1\%

(c)

2.43\,\text{g}

and

40.5\%

(d)

2.43\,\text{g}

and

59.5\%