Question

If you mixed 50 mL of 50°C hot water and 50 mL of 10°C cold water, what do you think the temperature of the mixture would be?

a) 30°C
b) 35°C
c) 40°C
d) 45°C

Answer 1

When mixing equal volumes of water at different temperatures without considering heat loss to the environment, the final temperature is the average of the initial temperatures, resulting in a mixture temperature of 30°C.

Step-by-step explanation:

When you mix 50 mL of 50°C hot water with 50 mL of 10°C cold water, the temperature of the mixture can be predicted by assuming that heat lost by the hot water will be equal to the heat gained by the cold water. Since the volumes and the specific heat capacities of the two water samples are assumed to be the same, the final temperature of the mixture will simply be the average of the two initial temperatures. Therefore, the temperature of the mixture would be:

• (50°C + 10°C) / 2 = 30°C

The correct answer is a) 30°C.