Answer to Question #177395 in Organic Chemistry for Shyana Mendis

Question

How much heat is needed to completely vapourize 3.6 g of propane (C₃H₈) at its boiling point?

Given: ΔH_vap = 15.7 kJ/mol

Answer 1

Molar mass of Propane gas =

3 ×12 + 1×8 = 44 g / mol.

Moles of Propane gas = 3.6 / 44

= 0.0818 mol.

Heat needed to Vapourise =

( 15.7 × 0.0818 ) Kj.

= 1.29 Kj .