How much heat q is needed to warm 300 g of water from 27 °C to 70 °C? The specific heat of water is 4.18 J/(g·°C). Give the answer in kJ.
Calorimetry & enthalpy worksheet with answers
25 kJ of heat is added to 200 g of water (c = 4.18 J/(g·°C)). Find the temperature rise ΔT.
A 200 g block of lead (c = 0.129 J/(g·°C)) at 120 °C is dropped into 200 g of water (c = 4.18 J/(g·°C)) at 15 °C in an insulated cup. Find the final temperature Tf.
A 100 g block of aluminium (c = 0.897 J/(g·°C)) at 150 °C is dropped into 250 g of water (c = 4.18 J/(g·°C)) at 23 °C in an insulated cup. Find the final temperature Tf.
Use the standard enthalpies of formation to find the heat q released when 10 g of C3H8 (M = 44.1 g/mol) burns completely: C3H8 + 5O₂ → 3CO₂ + 4H₂O(l). Give q as a positive number.
Use the standard enthalpies of formation to find the heat q released when 20 g of CH3OH (M = 32.04 g/mol) burns completely: 2CH3OH + 3O₂ → 2CO₂ + 4H₂O(l). Give q as a positive number.
Answer key
- 1. q = 53.92 kJ
- 2. ΔT = 29.9 °C
- 3. Tf = 18.14 °C
- 4. Tf = 33.04 °C
- 5. q = 503.4 kJ
- 6. q = 453.4 kJ
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