If the standard molar enthalpy change for combustion of graphite powder is $$-2.48 \times 10^2$$ kJ mol$$^{-1}$$, the amount of heat generated on combustion of 1 g of graphite powder in kJ (Nearest integer):

The combustion of graphite follows the reaction $$\text{C(s)} + \text{O}_2\text{(g)} \to \text{CO}_2\text{(g)}$$, with a standard molar enthalpy of combustion of $$-2.48 \times 10^2 = -248 \text{ kJ mol}^{-1}$$.

The molar mass of carbon (graphite) is $$12 \text{ g/mol}$$. For 1 g of graphite, the number of moles is $$\frac{1}{12}$$ mol. The heat generated is $$\frac{1}{12} \times 248 = 20.67 \text{ kJ}$$.

Rounding to the nearest integer, the answer is $$21$$ kJ.