- #1

Marcin H

- 306

- 6

## Homework Statement

10g of water at 0˚C added to 100g water at 50˚C

## Homework Equations

Qhot+Qcold=0

Q=mcΔT

Q=mL

Σmc(Tf-Ti)=0

## The Attempt at a Solution

So I understand this problem, but

**I'm not sure when I am supposed to use Q=mL**, L being the latency, I think. So with the problem mentioned you can do:

mw*cw(Tf-0) + mw*cw(Tf-50) = 0 and solve for Tf. Tf= 45.45˚K

What if I had a problem like

10g ice at 0˚C added to 100g water at 50˚C? Do you write the equation step by step starting at ice?

**And do I use Q=mL to account for phase changes only? [solid to liquid] and [liquid to gas]?**

mice*cice(Tf-0) +

**mL**+mw*cw(Tf-50) = 0

Solve for TF. I think this is set up correctly, but I am not sure. Can you explain the

**mL**part more? Is that the mass of ice * the latency of ice? This is where I get confused on how to do these problems.