Determine the latent heat of an unknown substance

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To determine the latent heat of the unknown substance X, the relevant energy equation is Q = mL, where Q is the total energy supplied, m is the mass, and L is the latent heat. Given that 3.0g of substance X is vaporized over 1.5 hours with an energy source of 10 kcal/hr, the total energy supplied is 15 kcal. The latent heat can be calculated by rearranging the equation to L = Q/m, which results in L = 15 kcal / 3.0g. The discussion emphasizes the need to show relevant equations and work for effective assistance. Understanding how to apply these principles is crucial for solving the problem.
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I need to determine the latent heat of an unknown substance X in kcal/g if 3.0g of boiling liquid X are completely vaporized in 1.5 hours by an energy source of 10kcal/hr.


Thanks a million!


Dave
 
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Welcome to the PF, dhkdl1. Homework and coursework questions like this need to be posted in the appropriate forum in the Homework Help section of the PF, and not in the general technical forums. I've moved your thread to the Homework Help forums, leaving a redirect in the general technical forum.

And on questions like these, you are required to show us the relevant equations and some of your own work, in order for us to be able to provide some tutorial help to you.

So what equations do you think apply here?
 
still need help!

dhkdl1 said:
I need to determine the latent heat of an unknown substance X in kcal/g if 3.0g of boiling liquid X are completely vaporized in 1.5 hours by an energy source of 10kcal/hr.


Thanks a million!


Dave

The formula my book show for Q=cmdelta T, I guess what I reaaaallllyyy need to know is how to find deltaT given the above problem and then the Lv(latent heat of the unknown substance). This too is a distance learning experience. So please point me in the right direction
 
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