Q = cm t (raising water temperature -- answer given looks wrong)

Thread starter Stacie Worrel
Start date Apr 16, 2015
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Temperature Water

In summary, the equation Q = cm t is used to calculate the amount of heat required to raise the temperature of a substance. It considers the mass of the substance, the change in temperature, and the specific heat capacity (c) of the substance. This equation can be used for all substances, but the specific heat capacity will vary. It is commonly used in real-world applications such as cooking, heating and cooling systems, and industrial processes. However, there is a limit to its accuracy when used with water at very high temperatures, as the specific heat capacity and mass of water can change.

Apr 16, 2015

Stacie Worrel

Hey ya'll my question reads:
Use the formula Q = cmt to show that 300 cal are requited to raise the temperature of 300g of water from 22 degrees C to 30 degrees C. For the specific heat capacity c, use 1 cal/g degrees C.

now i don't see how this math adds up, doesn't that equal 2400?

Thanks in advance!

Last edited by a moderator: Apr 16, 2015

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Apr 16, 2015

nasu

Homework Helper

It seems like you are right. Assuming you wrote the problem as it is in the source.

FAQ: Q = cm t (raising water temperature -- answer given looks wrong)

1. How does the equation Q = cm t relate to raising water temperature?

The equation Q = cm t is known as the heat equation, where Q represents the amount of heat transferred, c is the specific heat capacity of the substance, m is the mass of the substance, and t is the change in temperature. This equation shows that the amount of heat required to raise the temperature of a substance is directly proportional to its mass and the change in temperature.

2. What is the specific heat capacity (c) in the equation Q = cm t?

The specific heat capacity (c) is a physical property of a substance that describes how much heat energy is required to raise the temperature of a unit mass of that substance by one degree. It is measured in units of joules per gram per degree Celsius (J/g°C).

3. Can this equation be used for all substances?

Yes, this equation can be used for all substances, as long as the values for Q, c, m, and t are given in the appropriate units. However, the specific heat capacity (c) will vary for different substances, as it depends on the molecular structure and composition of the substance.

4. How is this equation used in real-world applications?

The heat equation (Q = cm t) is used in various real-world applications, such as in cooking, heating and cooling systems, and industrial processes. It helps in calculating the amount of heat energy needed to raise the temperature of a substance, which is essential in controlling and regulating temperature in various processes.

5. Is there a limit to how much the temperature of water can be raised using this equation?

Yes, there is a limit to how much the temperature of water can be raised using the equation Q = cm t. This is because the equation assumes that the specific heat capacity (c) and the mass (m) of the substance remain constant, which is not the case for water at very high temperatures. At high temperatures, the specific heat capacity of water decreases, and its mass can also change due to evaporation. Therefore, the equation becomes less accurate as the temperature of water increases beyond a certain point.