# Finding how much heat it takes to vaporize

## Homework Statement

How much heat does it take to vaporize 600g of lead that is initially at 34°C?

## Homework Equations

heat capacity=1.3X102

## The Attempt at a Solution

ΔT = 1750°C - 34°C
= 1716 ° C

Q= m X c X ΔT
= 0.6 X 1.3X102 X 1716
=133,848 J

Am I suppose to factor in the change of state? Is there latent vaporization?

## Answers and Replies

You've answered your own question. Think about the analogy of turning water to vapor.

rock.freak667
Homework Helper
Q= m X c X ΔT
= 0.6 X 1.3X102 X 1716
=133,848 J

Am I suppose to factor in the change of state? Is there latent vaporization?

Yes you are, Q = mcΔT just gives you the heat required to raise the temperature from 34°C to 1716°C.

You just need to use Q=mlvap now and add them.

PeterO
Homework Helper

## Homework Statement

How much heat does it take to vaporize 600g of lead that is initially at 34°C?

## Homework Equations

heat capacity=1.3X102

## The Attempt at a Solution

ΔT = 1750°C - 34°C
= 1716 ° C

Q= m X c X ΔT
= 0.6 X 1.3X102 X 1716
=133,848 J

Am I suppose to factor in the change of state? Is there latent vaporization?

I not sure lead will even by molten at 34o, so you may have to melt it too. ANd is the heat capacity of solid lead and liquid lead the same?