Finding latent heat of vaporization from evaporation rate

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Homework Statement



A scientist heats up a substance by applying heat at a constant rate of 75 J/s. She measures that
it takes 1 minute for 100 grams of the substance to evaporate. What is the latent of vaporization
of this substance? If she starts with 1 kg of the substance, how long will it take for it to
evaporate and how much energy will it take to evaporate the substance?

Homework Equations



Q=mL?

3. The Attempt at a Solution [/b

I'm not really sure how to use Q=mL. Does 75 J/s go into Q or is Q the total amount of joules. I know m is the mass and L is the specific latent heat.
 
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Bgerst103 said:

Homework Statement



A scientist heats up a substance by applying heat at a constant rate of 75 J/s. She measures that
it takes 1 minute for 100 grams of the substance to evaporate. What is the latent of vaporization
of this substance?

I will use the formula ##E=mL_v## for easiness.
J/s is the unit of power so if you know the power and the time,you should be able to find the energy supplied.
Use##E=mL_v## to find the ##L_v##.
 
adjacent said:
I will use the formula ##E=mL_v## for easiness.
J/s is the unit of power so if you know the power and the time,you should be able to find the energy supplied.
Use##E=mL_v## to find the ##L_v##.

So, 75 x 60 is equal 4500. 4500= (.1kg)(L) -> L=45000. If it takes 1 minute to vaporize 100g it should take 10 minutes for a kg and 45000 J?
 
Bgerst103 said:
So, 75 x 60 is equal 4500. 4500= (.1kg)(L) -> L=45000. If it takes 1 minute to vaporize 100g it should take 10 minutes for a kg and 45000 J?
Correct.
 
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