Chemistry

When you multiply a balanced equation by 3, you're tripling the amount of reactants and products involved—so the total heat released or absorbed also triples. The key insight is that $\Delta H^\circ$ is an extensive property: it scales with the quantity of reaction. Think of it like doubling a recipe; you don't just make twice as much food, you also use twice as much energy to cook it. So if the original $\Delta H^\circ$ was $-100$ kJ, multiplying the equation by 3 gives $3 \times (-100) = -300$ kJ.

When you multiply a balanced equation by 3, you're tripling the amount of reactants and products involved—so the total heat released or absorbed also triples. The key insight is that $\Delta H^\circ$ is an extensive property: it scales with the quantity of reaction. Think of it like doubling a recipe; you don't just make twice as much food, you also use twice as much energy to cook it. So if the original $\Delta H^\circ$ was $-100$ kJ, multiplying the equation by 3 gives $3 \times (-100) = -300$ kJ.