Fats that contain double bonds are liquids at room temperature, whereas fats that contain double bonds are solids at room temperature.

The answer ;  double,   single

In unsaturated oils, the double bonds cause the hydrocarbon chains to have kinks hence do not allow adjacent hydrocarbon chains to form enough hydrogen bonds between each other. Therefore, chains are not compact enough even at low energetic levels (at room temperature).

In saturated oils, the single-bond hydrocarbon chains have numerous hydrogen bonds between adjacent chains that they become compact at room temperature (when their molecules have low energy levels)  

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