Anonymous
Anonymous asked in Science & MathematicsChemistry · 5 months ago

# Help with checking my answers?

First question is, “Suppose that we have a container of 500 grams of water to which we apply 2000 calories of heat energy (assume no other sources or sinks of heat). The specific heat of water is 1 calorie per gram per Celsius degree. Assume the water has an initial temperature of 10oC. What will the temperature be after the heat energy is applied?” I think I misinterpreted how to do the problem, but I got 40 degrees Celsius. That doesn’t feel right to me.

Second one, “We have a container of 500 grams of sand to which we apply 2000 calories of heat energy (assume no other sources or sinks of heat). The specific heat of sand is 0.188 calories per gram per Celsius degree. Assume the sand has an initial temperature of 10oC. What will the temperature be after the heat energy is applied?” When I did this problem the way I think I should’ve done the other, I got a decimal. I think I am confusing myself with these problems and how to complete them. Any help?

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• 5 months ago

(2000 cal) / (1 cal/g·°C) / (500 g) = 4°C change

10°C + 4°C = 14°C

(2000 cal) / (0.188 cal/g·°C) / (500 g) = 21.276°C change

10°C + 21.276°C = 31°C

• 5 months ago

I use the following equation to calculate the increase of the temperature of the water.

Q = mass * specific heat * ∆ T

2,000 = 500 * 1 * ∆ T

∆ T = 4˚

The final temperature is 14˚ C. Let’s use the same equation to calculate the increase of the temperature of the sand.

2,000 = 500 * 0.188 * ∆ T

∆ T = 2,000 ÷ 94

This is approximately 21.3˚C. The final temperature is approximately 31.3˚. I hope this is helpful for you.

• 5 months ago

water is measured in millilitres.

• 5 months ago

I think it should be 14 degrees Celcius for the first one. I took Chem last year, but I thought each calorie heats 1 gram, 1 degree. 2000/500 = 4, so the entire container is increased by 4 degrees to 14 (started at 10). Is this not correct?

Likewise, for the second problem, I reached an answer of 31.28 degrees Celcius, which makes sense if the first answer is right, because water has a very high specific heat, so for the same mass and energy, the sand should reach a greater temperature.