Ethane, C2H6, and ammonia, NH3, are covalent compounds. The dot-and-cross diagrams of these compounds are shown. [Dot-and-cross diagrams for ethane (C2H6) and ammonia (NH3)]. Which statements are correct? 1 A molecule of ethane contains twice as many hydrogen atoms as a molecule of ammonia. 2 An unreacted nitrogen atom has five outer-shell electrons. 3 In a molecule of ethane, the bond between the carbon atoms is formed by sharing two electrons, one from each carbon atom.

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