Question

Consider the following hydrides and their boiling points: H20, 373 K HF, 293 K NH3, 240 K CH4, 111 K (0) Draw the Lewis structure of each of these hydrides [2 marks]. (ii) Explain the origin of the difference in boiling points between them. (3 marks (Hint: Consider the structures of these compounds and the main type of intermolecular forces.)

Answer 1

CHy NH2 H-F H-A H H-CH H2O, HF, NH Can fom Aydrogen lorerding dueto high electronegativihy of F,o,N. it i one d the tyfe of eleetmeegad electoostatic force f athaction ebist between moee electoonegathue atom (F0,N) and Hydrogen atom brodea eith theve atom uoith othoe Bame molecule one moleaule of oatee Gn form hpnoit Ra Righ booiling point than HF and Nt Deto igh eleetronegativity o fluorine atom than nitoogen it an form strong hydogen bord than Nitoogen o it Aau high boiling point than NH force woulo eoist that's wohy it Ra lous Dei ling point H-FH-.- H H H H