Please help! I need these done by wednesday and for the life of me i cannot seem to get the correct answer.(adsbygoogle = window.adsbygoogle || []).push({});

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

How much ice must melt at 0 deg. C to gain 5 g of mass?

2. Relevant equations

I cannot seem to find many equations that relate thermodynamics and mass, maybe that is my biggest problem... The only one i could find was

Q=Lm

3. The attempt at a solution

I know the latent heat of fusion, but i do not know Q. I tried dividing both sides by L, giving me Q/L=m, but i wasn't sure where to go from there.

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

Calculate the entropy change in isotermal transformation of ideal gas at the temperature of 27.5 deg. C if work done by the gas is 3.5 J.

2. Relevant equations

s(b)-s(a)=Cv*ln(Tb/Ta)+nR*ln(Vb/Va)

pV=nRT

dW=pdV

3. The attempt at a solution

since Tb/Ta=1, Cv*ln(Tb/Ta) is reduced to zero, leaving us with

s(b)-s(a)=nR*ln(Vb/Va)

i then attempted to use the ideal gas law combined with dW=pdV but i found myself running in circles trying to figure out what to do with p and n and trying to find Vb and Va at the same time.

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# Homework Help: Two Fairly Basic Thermodynamics Questions

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