Question

For the following reaction, calculate how much heat will be released when 8 g of hydrogen reacts?

(1 mole of $H_2$ weighs approximately 2 grams.)
$2H_2\left(g\right)+O_2\left(g\right)\to 2H_{2}O\left(g\right)$
$\Delta H=-115.60kcal$

• A. 57.8 kcal
• B. 115.6 kcal
• C. 173.4 kcal
• D. 231.2 kcal

Answer 1

The correct option is D 231.2 kcal

$2H_2\left(g\right)+O_2\left(g\right)\to 2H_{2}O\left(g\right)$ ,$\Delta H=-115.60$ kcal

Through this reaction ,we can infer that 4g of hydrogen is relasing a heat of $-115.60$kcal.

For 8g of hydrogen: the heat libereted$=2(-115.60)=231.2$ kcal