Question

What will be the work done, when one gram of ice at -10° C is converted into steam at 100°?

Options

• 3045 J

• 6056 J

• 721 J

• 616 J

Answer 1

3045 J

Explanation:

Ice (- 10° C) converts into steam as follows (c_i = Specific heat of ice, c_w= Specific heat of water, L_f = Latent heat of fusion and L_v = Latent beat of vaporization)

Total heat required

`"Q" = "Q"_1 + "Q"_2 + "Q"_3 + "Q"_4`

`= "mc"_"i" Delta theta_1 + "mL"_"f" + "mc"_"W" Delta theta_2 + "mL"_"V"`

`= 1 xx 0.5 (10) + 1 xx 80 + 1 xx 1 xx (10 - 0) + 1 xx 540`

`= 725  "cal"`

Work done W = JQ

= 4.2 x 725

= 3045 J