In a CIS fatty acid, the hydrogen atoms are ON THE SAME SIDE of the double bond, which produces a kink in the carbon chain.
In a TRANS fatty acid, the hydrogen atoms are ON OPPOSITE SIDE of the double bond, which gives a carbon chain without any kink.
In unsaturated fatty acids (with one or more double bonds between carbon atoms), the cis double bonds cause the carbon chain to bend (kink), which gives the molecules an irregular shape (see the picture below).
Cis fatty acids are not as close as trans fatty acids, so they have fewer dispersion forces between their carbon chains.
Cis fatty acids have lower melting and boiling points than trans fatty acids.
More about cis and trans isomers: brainly.com/question/10407072
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