How do saturated triglycerides compare to unsaturated triglycerides in how tightly they pack together?

Answer and Explanation:

In saturated triglycerides structure, the fatty acids chains are composed by  carbon-chains with single bonds between carbons. The chains can be aligned with each other and are more easily packed, thus the interaction strenght is higher. For that reason, saturated triglycerides are solid at room temperature.

By other hand, unsaturated triglycerides are composed by fatty acids which  contain one (monounsaturated) or more (polyunsaturated) double bond(s) between the carbons and in consequence, the molecule bends. The bended chains cannot be packed efficiently, so the interaction strenght is lower and this kind of fats melt at lower temperatures.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.