Question

1 The melting point of copper is 1083C it’s heat of fusion is 32 cal/g and it’s heat capacity (specific heat) is 0.093 cal/gC. Starting at 20C, how much heat would it take to melt 30g of copper ?

2 How do you know when molecule is ionic, diapole diaploe or non polar ?

Answer 1

Question 1.

The heat (q_total) that would be taken by 30 g of copper to melt from 20 ^oC, can be calculated as shown below.

q_total = (q)_Cu(s) + (q)_fusion

= {m.C.(T2-T1)}_Cu(s) + m.(H_fus)

Where 'm' is the mass of copper.

'Ç' is the specific heat of copper = 0.093 cal/g.^oC

H_fus is the heat of fusion (heat required to melt copper, i.e. from solid to liquid phase) = 32 cal/g

Therefore, q_total = 30 g*0.093 cal/g.^oC*(1083 - 20) ^oC + 30 g*32 cal/g

= 2965.77 cal + 960 cal

Therefore, the amount of heat that would be taken by 30 g of copper to melt from 20 ^oC (q_total) = 3925.77 cal or 3.926 kcal