NJC 5T Chemical Bonding Tutorial Student

National Junior College SH1 H1 Chemistry 1 CHEMICAL BONDING TUTORIAL Interatomic Bonding 1 Using the list below, give one example to each of the following solid lattices showing the given properties. Name the structure and type of bonding found in each lattice. graphite, diamond, copper, iodine, sodium chloride (a) A hard and brittle solid. (b) A solid that conducts electricity and melts at 1085 C. (c) A solid that cuts through metal and does not conduct electricity. (d) A substance that sublimates when heated. (e) A solid that can be used as a lubricant. 2 Which statement(s) are correct? I HCl (g) can conduct electricity. II Covalent bond is a weak bond compared to ionic bond as boiling point of H2O is lower than that of MgO. III Ionic bonds and covalent bonds can both occur in the same compound. IV Metals can be distinguished from ionic compounds by their electrical conductivity in the solid and liquid state. A Statements I and III are correct. B Statements II and IV are correct. C Statement III and IV are correct. D Statements I, III and IV are correct 3 Boron trifluoride and ammonia reacts in a 1:1 mole ratio to form a single compound. Describe the type of bond formed during this reaction. 4 Explain the following observations in terms of structure and bonding. i. MgO has a higher melting point than NaCl. ii. At room temperature and pressure, CO 2 is a gas, while SiO2 is a solid of high melting temperature.

National Junior College SH1 H1 Chemistry 2 Dot-and-Cross Diagram and VSEPR 5 Fill up the table below for the following compounds: compound ‘dot-and-cross’ diagram (i) Draw and name the shape of the covalent molecule or polyatomic ion (ii) Indicate the bond angle in the diagram Bonds or intermolecular forces broken during melting or boiling process (i) Al2O3 (m.p. 2072C) Ionic compound Ionic bond (ii) AlCl3 (m.p. 192C) Covalent molecule Weak intermolecular forces (iii) PCl3 (l) (iv) CH2Cl2(l) (v) PCl5(s) (vi) HCN

National Junior College SH1 H1 Chemistry 3 compound ‘dot-and-cross’ diagram (i) Draw and name the shape of the covalent molecule or polyatomic ion (ii) Indicate the bond angle in the diagram Bonds or intermolecular forces broken during melting or boiling process (vii) SO2 (viii) SO3 (ix) H2O2 (H-O-O-H arrangement) (x) (NH4)2SO4 Ionic bond

National Junior College SH1 H1 Chemistry 4 6 A stable molecule containing atoms of the elements, X, Y and Z has the following structure. Which option is a possible combination of the elements? X Y Z A N P Cl B O S Cl C B N H D P O F 7 MTBE is a constituent of petrol. What are the values of angle P and angle Q in a molecule of MTBE? angle P angle Q A 90o 105o B 90o 180o C 109o 105o D 109o 180o 8 Using VSEPR theory, predict which compound in each of the following pair of