A student suspects that the power rating on an immersion heater is 50 W but he is not sure.He sets up an apparatus as shown. After the liquid has been brought to its boiling point, he finds that 3.5g of vapor escaped each minute through the outlet tube.The boiling point of the liquid is 80 degrees celcius.(adsbygoogle = window.adsbygoogle || []).push({});

Calculate the heat required to convert 3.5 g of liquid at its boiling point to 3.5g of vapor at the same temperature.

My attempt :

I know that to find the energy required for a phase change would be q=mass x latent heat of vaporization Q=mxl_{v}

But i don't know what it is the latent heat of vaporization of the material.

I'm thinking something like :

50 W = 50 joules per second so in one minute 50x60 3000 joules would be expended....but the answer that my book has is 2940J ! and I don't know where to move from here. Any help at all would be awesome ! Thanksss alot :D

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Heat of vaporization ( thermal physics) helppp pleasee ?

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