How much heat q is needed to warm 250 g of water from 15 °C to 75 °C? The specific heat of water is 4.18 J/(g·°C). Give the answer in kJ.
Calorimetry & enthalpy worksheet with answers
40 kJ of heat is added to 250 g of water (c = 4.18 J/(g·°C)). Find the temperature rise ΔT.
A 200 g block of aluminium (c = 0.897 J/(g·°C)) at 170 °C is dropped into 250 g of water (c = 4.18 J/(g·°C)) at 24 °C in an insulated cup. Find the final temperature Tf.
A 250 g block of lead (c = 0.129 J/(g·°C)) at 170 °C is dropped into 300 g of water (c = 4.18 J/(g·°C)) at 21 °C in an insulated cup. Find the final temperature Tf.
Use the standard enthalpies of formation to find the heat q released when 250 g of C4H10 (M = 58.12 g/mol) burns completely: 2C4H10 + 13O₂ → 8CO₂ + 10H₂O(l). Give q as a positive number.
Use the standard enthalpies of formation to find ΔH° for the reaction C6H12O6 + 6O₂ → 6CO₂ + 6H₂O(l).
Answer key
- 1. q = 62.7 kJ
- 2. ΔT = 38.28 °C
- 3. Tf = 45.39 °C
- 4. Tf = 24.74 °C
- 5. q = 12377 kJ
- 6. ΔH° = −2802 kJ
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