Question

What is the amount of heat given off by 100g of $O_2$ when it is used to burn an excess of sulfur according to the following reaction?
$S\left(s\right)+O_2\to S{O}_2\left(g\right)$ $\Delta H=-296kJ/mole$

• A. 925,000 J
• B. 29,000 J
• C. 1,850 J
• D. 296 J
• E. 100 J

Answer 1

The correct option is A 925,000 J

Here $\Delta H$ is negative, which means heat is produced or given out by a reaction. The equation says-

$S$ $+$ $O_2$ $\to$ $S{O}_2$, which gives off $296kJ$ or $296000J$ of heat.

One mole of Oxygen is equal to $32grams$

From the equation, it is seen that-

$32grams$ of Oxygen gives off $296000J$ of heat

$1gram$ of Oxygen gives off $\frac{296000}{32}$$J$ of heat

Thus, $100grams$ of Oxygen gives off $\frac{296000}{32}$$\ast$$100J$, that is equal to $925000J$ of heat.

Option $A$ is the correct answer.