Question

***Help Checking Study Guide Answer***
Find the amount of heat energy needed to convert 400 grams of ice at -38°C to steam at 160°C.

Select one:
a. 246840 Joules
b. 331056 Joules
c. 1284440 Joules
d. 159984 Joules

I got A.) but have no idea how to check if my answer is correct or incorrect.

Answer 1

Oh man, these problems take a ton of steps. I'll give it a try though

Answer 2

I'm not getting the exact answer, but my answer is very close to one of those choices, and it's not A. If you worked your answer for A, it's likely that you forgot to add up the melting heat of fusion and vaporization energies. I'll walk you through it.

1. Energy to make ice cube to go melting point (0 degrees cel)
400x2.06x38=

2. Energy for the phase change of solid to liquid
400x333=

3. Energy to make the now liquid water, to boiling point (100 degrees cel)
400x4.19x100=

4. Energy for phase change from liquid to gas
400x2260=

5. Energy for steam to go to 160 degrees cel
400x2.02x60=

add those all up and the answer is very close to one of yours.

Answer 3

Haha, thanks dude. Lemme grab some paper and work it out

Answer 4

What I got was WAY off.

1.31312
2.133200
3.167600
4.904000
5.48480

Added all together I got 2792992

Answer 5

Just redid. Is the answer C?

Answer 6

ya

Answer 7

Ahh! Thanks Dan. You're honestly amazing. I found the formula and it REALLY helped. (>o<)