Question

the heat of fusion for thallium is 21 J/g, and its heat of vaporization is 795 J/g. Thallium's melting point is 304 degrees celsius, and its boiling point is 1457 degrees celsius. The specific heat of liquid thallium is 0.13 J/g degrees celsius. How much heat is needed to change 236 g of solid thallium at 304 degrees celsius to vapor at 1457 degrees celsius and 1 atm?

Answer 1

q1 = heat to melt Tl at 306 C.
q1 = mass x heat fusion.

q2 = heat to move Tl from 306 C to 1457 C.
q2 = mass x specific heat liquid Tl x delta T.

q3 = heat to vaporize Tl
q3 = mass x heat vaporization.

Total Q = q1 + q2 + q3.

Answer 2

12