Thermodynamics: heat needed to melt block of a metal

[teggenspiller]

Homework Statement

the latent heat of fusion for this metal is 500Cal/kg. The latent heat of vaporization is 600Cal/kg and specific heat of the liquid metal is 500C/kg K. How much heat is needed to melt an 8kg block of this metal when its temperature is exactly at the melting point?

Homework Equations

T= kelvins
c=specific heat
Q is heat needed

Q= m*c*delta T
Q=m*Latent heat (either fusion or vapor)

The Attempt at a Solution

Q= 8 * 500Cal/kg


Will someone please sho wme how to do this>?

 

[danago]

What makes you think your answer is wrong?

 

[teggenspiller]

The answer was 1600..?

 

[teggenspiller]

thats the problem. my coices are 400, 100, 200, 1600 and none of the above. and i answered none the above, but answer is 1600.

 

[gneill]

thats the problem. my coices are 400, 100, 200, 1600 and none of the above. and i answered none the above, but answer is 1600.

But the answer is clearly NOT 1600. So apparently the marker (or marking program) or the question statement is wrong.

 

[danago]

What units are the answers given in? The only thing i can think of is that the answers are given in some unit besides Calories? Either that, or the answers are wrong.

 

[mukundpa]

what are the units of energy, cal or cal/kg ?

 

[teggenspiller]

ahg i see.