An alkane is a carbon-based molecule comprised of only single bonds (-), whereas an alkene is comprised of at least one double bond (=). If a molecule has no double bonds, it can be classified as an alkane, but if it has at least one double bond it can no longer be classified as such.
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The answer is C because kinetic energy is energy which a body possesses by virtue of being in motion.
Mass of 1mole of Na is weight for 24g
Where as,1mole of Fe weight for 56g