Question 17
Quantity of Heat200g of water at 90°C is mixed with 100g of water at 30°C. What is the final temperature?
- A.50°C
- B.60°C
- C.70°C
- D.80°C
Show the answer and explanation
Answer: C (70°C)
Explanation
Heat lost = heat gained: 200(90 − θ) = 100(θ − 30), so 18 000 − 200θ = 100θ − 3000 and θ = 70°C.