Homework 6 (due before 11th May 2009) (part 1)

Dear CH304

There are two questions in today's assignment. Please copy question 1 and answer it on a piece of writing paper. Submit you answers before Tuesday's assembly.

Question 1 - Done in writing paper.
(a) Draw the dot and cross diagrams of (i) N₂O (ii) O₃ (iii) HNO₃ (iv) H₃PO₄.
[Hint: (iii) and (iv) are mineral acids. As they are mineral acids they have at least one O-H.]

(b) Draw the lewis structure of H₂O₂. On this diagram, label all bond angles. In addition, determine the shape of H₂O₂.

(c) XeF₂ is one of the most stable Xenon compounds. (i) Draw the dot and cross diagram of XeF₂. (ii) Predict with explanation which bond is stronger Xe-F or He-F.

(d) Suggest an explanation for the following suitations. (i) MgCl₂ has stronger interatomic bonds than NaCl. (ii) Given that the bond energy of C-Cl is 328 kJmol^-1 and while the C-N is 292 kJ mol^-1.

[Marks allocation for Q1: 3 + 4 + 4 + 4]

Suggested Solutions




Comments
(1) Becareful with your explanation in (c)(ii) - It cannot be a contradiction.

(2) Becareful with your explanation in (d)(ii) - It cannot contradict the given data. Hence, atom size for effective overlap isn't suitable. Lone pair repulsion is irrelevant as C does have that.