An average person needs about 10000 kJ energy per day. The amount of glucose (molar mass = 180.0 g ) — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

**Step 1: Identify the combustion reaction and energy released** The combustion of glucose is: C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l) The standard enthalpy of combustion is ΔH = -2800 kJ/mol (energy released per mole of glucose burned) **Step 2: Calculate moles of glucose needed** Using the formula: $$\text{Moles of glucose} = \frac{\text{Total energy required}}{\text{Energy per mole}}$$ $$\text{Moles} = \frac{10000 \text{ kJ}}{2800 \text{ kJ/mol}} = 3.571 \text{ mol}$$ **Step 3: Convert moles to grams** Use molar mass of glucose = 180.0 g/mol $$\text{Mass} = \text{Moles} \times \text{Molar mass}$$ $$\text{Mass} = 3.571 \text{ mol} \times 180.0 \text{ g/mol} = 642.9 \text{ g}$$ **Step 4: Round to nearest integer** Mass ≈ 643 g *Note: If the given ΔH = -2700 kJ/mol is used instead:* - Moles = 10000/2700 = 3.704 mol - Mass = 3.704 × 180.0 = 666.7 ≈ **667 g** Therefore, the answer is 667.00.