Question

diethyl ether (MM= 74.14g/mol) is often sprayed into carburetors to help get cars started on very cold winter mornings. How many kilojoules are required to vaporize 15.8 g of diethyl ether? The heat of vaporization is 27.8 kJ/mol

a) 5. 92 kJ

b) 42. 1 kJ

c) 13.0 kJ

d) 439 kJ

Answer 1

The energy required in KJ to vap ourize diethyl ether can be calculated as. q=nX AHV. where, q= Energy in KJ. n= No. of moles of diethyl ether. sHv = Heat of vapourization = 27.8 KIlmu). Now, calculate number of moles (n). in where, W = given mass of diethyl ether=15. 8g M = molar mass of diethyl ether = 74.14 gimol, in=15.8 g = 0.213 Moles. 74.14 g/mol. - n=0.213 moles. :. The energy required will be. to rapourize diethyl ether q=nx AHV. q = 0.213 mol X 27.8 Kolmo). 19=5.92 KJ / option =a