Question

$X_{(g)} \longrightarrow X^{+}(g)+e^{-}$,
$\Delta H=+720\, kJ\, mol ^{-1}$
Calculate the amount of energy required to convert $110\, mg$ of ' $X$ ' atom in gaseous state into $X^{+}$ion. (Atomic wt. for $X=7 g / mol$ )

• A. 10.4 kJ
• B. 12.3 kJ
• C. 11.3 kJ
• D. 14.5 kJ

Answer 1

Answer: (C)

Energy required for $1 mol=720 \times 10^3 J$
According to question-
Energy required for $110 mg =720 \times 10^3 \times\left(\frac{110 \times 10^{-3}}{7}\right)$
$=11314.2 J=11.3 kJ$