Hydrogenation of ethene is represented by C H (g) + H (g) → C H (g)

CHEMISTRY · Single correct · A Level · Chemistry · Energetics · Energetics

Problem

Hydrogenation of ethene is represented by C

_2

_4

(g) + H

_2

(g) → C

_2

_6

(g)

\Delta H_{\text{rxn}} = -136\,\text{kJ}\,\text{mol}^{-1}

. A chemical plant needs this reaction to release

4.08\times10^{3}\,\text{kJ}

of heat. If the process operates at a

75\%

yield with respect to C

_2

_4

, what mass of ethene (in grams) must be fed into the reactor? (a)

8.40\times10^{2}\,\text{g}

(b)

6.30\times10^{2}\,\text{g}

(c)

1.12\times10^{3}\,\text{g}

(d)

1.20\times10^{3}\,\text{g}