Question

Ethyl chloride (C2H5Cl) boils at 12 degrees celcius. When liquid C2H5Cl under pressure is sprayed on a room-temperature (25 degrees celcius) surface in air, the surface is cooled considerably.

a) What does this observation tell us about the specific heat of C2H5Cl(g) as compared with C2H5Cl(l)?

b) Assume that the heat lost by the surface is gained by ethyl chloride. What enthalpies must you consider if you were to calculate the final temperature of the surface?

Answer 1

Ethyl chloride (C2H5Cl) boils at 12 degrees Celsius. When liquid C2H5Cl under pressure is sprayed on a room-temperature (25 degrees Celsius) surface in the air, the surface is cooled considerably.

it is removing heat from the room temperature surface & using it as its "heat of Vaporization" , the required heat to change it from liquid to gas.

much the same as perspiring cools you off   

Answer 2

Answer:

a) Liquid ethyl chloride is a volatile solvent , requires more heat to raise the temperature in each gram of substance, its counterpart grade gas.

b) $\Delta H = \frac{Q_l_o_s_t}{T_e_q}$ (just explicit, no process)