Molecules such as CO2 and H2O are formed through covalent bonding.
2.1 Define the term covalent bonding. (2)
2.2 ONE of the above molecules has lone pairs of electrons on the central atom. Draw the Lewis diagram for this molecule. (2)
2.3 H3O+ is formed when H2O forms a dative covalent bond with an H+ ion.
2.3.1 Draw the Lewis diagram for H3O+. (1)
2.3.2 State TWO conditions for the formation of such a bond. (2)
2.4 The polarity of molecules depends on the DIFFERENCE IN ELECTRONEGATIVITY and the MOLECULAR SHAPE.
2.4.1 Define the term electronegativity. (2)
2.4.2 Calculate the difference in electronegativity between:
(a) C and O in CO2 (1)
(b) H and O in H2O (1)
2.4.3 Explain the difference in polarity between CO2 and H2O by referring to the polarity of the bonds and the shape of the molecules. (6)
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