M/J 2016/P12/Q8
Ethene, C2H4, is a covalent compound with a simple molecular structure.
Which statement about ethene is correct?
A Ethene is a liquid at room temperature and pressure.
B Liquid ethene conducts electricity.
C One ethene molecule contains sixteen protons.
D The total number of shared pairs of electrons in ethene is five.
Answer: C
Explaination
As its physical property, alkene exists as a gas at normal room temperature and pressure not as a liquid. In ethene there is a covalent bond (mutual sharing of electrons) among the atoms so there is no free electron available to conduct electricity. The total shared pair of electrons in ethene with molecular formula C2H4 are 8(4 C=C) and (4 C - H). One ethene molecule contains sixteen protons as:
C2H4: 2(6) +4(1) = 12+4 = 16 protons
