Need some help with heat homework

In summary, a 1.0kg sample of metal with a specific heat of 0.50 KJ/KgC is heated to 100.0C and then placed in a 50.0g sample of water at 20.0C. The final temperature of the metal and the water can be found by using the equation for heat energy, where the heat energy of the metal is equal to its mass multiplied by the difference between the final and initial temperatures, multiplied by its specific heat. The heat energy of the water can be found in a similar manner, using the mass of the water and its specific heat.
  • #1
defult986
1
0
A 1.0kg sample of metal with a specific heat of 0.50 KJ/KgC is heated to 100.0C and then placed in a 50.0g sample of water at 20.0C. What is the final temperature of the metal and the water?



Heat energy=mass*(Final temp.-initial temp.)*Specific Heat



i have no idea how to even start
 
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  • #2
Let the initial temp. of the metal be [itex]\theta[/itex]

Assuming no heat losses,all the heat from the metal goes into increasing the temperature of the water.

Heat energy=mass*(Final temp.-initial temp.)*Specific Heat

Find the heat energy the metal has when it's final temperature is 100 and initial is [itex]\theta[/itex].

For the water, the initial temperature is 20. Can you find a similar expression for heat energy?
 
  • #3
this

Hello,

I can assist you with this problem. To find the final temperature of the metal and water, we will use the equation you provided:

Heat energy = mass * (final temp. - initial temp.) * specific heat

First, let's calculate the heat energy of the metal. We know the mass of the metal is 1.0kg and its specific heat is 0.50 KJ/KgC. We also know that the initial temperature of the metal is 100.0C and we want to find the final temperature. So, we can rewrite the equation as:

Heat energy of metal = 1.0kg * (final temp. - 100.0C) * 0.50 KJ/KgC

Next, let's calculate the heat energy of the water. We know the mass of the water is 50.0g, which is equivalent to 0.050kg. We also know the initial temperature of the water is 20.0C and we want to find the final temperature. So, we can rewrite the equation as:

Heat energy of water = 0.050kg * (final temp. - 20.0C) * 1 KJ/KgC

Now, we can set these two equations equal to each other since the heat energy of the metal and the water will be the same when they reach thermal equilibrium:

1.0kg * (final temp. - 100.0C) * 0.50 KJ/KgC = 0.050kg * (final temp. - 20.0C) * 1 KJ/KgC

Simplifying this equation, we get:

0.5(final temp. - 100.0C) = final temp. - 20.0C

0.5final temp. - 50.0C = final temp. - 20.0C

0.5final temp. - final temp. = 50.0C - 20.0C

-0.5final temp. = 30.0C

Finally, we can solve for the final temperature of the metal and water by dividing both sides by -0.5:

final temp. = 30.0C / -0.5

final temp. = -60.0C

So, the final temperature of both the metal and water will be -60.0C
 

What is heat?

Heat is a form of energy that is transferred from one object to another due to a difference in temperature.

What are the units of heat?

The units of heat are joules (J), calories (cal), and British thermal units (BTU).

How is heat measured?

Heat is measured using a thermometer and the unit of measurement is degrees Fahrenheit (°F) or degrees Celsius (°C).

What is the difference between heat and temperature?

Heat is the energy that is transferred between objects, while temperature is a measure of the average kinetic energy of the particles in an object.

How does heat transfer occur?

Heat transfer can occur through three main methods: conduction, convection, and radiation. Conduction is the transfer of heat through direct contact, convection is the transfer of heat through the movement of fluids, and radiation is the transfer of heat through electromagnetic waves.

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