Question

1. If you looked at a drawing of a lipid, how could you tell whether it was saturated or unsaturated?

2. Describe an example of kinetic energy being transformed into potential energy.

3. Describe an example of potential energy being transformed into kinetic energy.

4. What makes something an organic molecule?

5. How can you tell if a solution is a good buffer or not?

Answer 1

1) Lipids have two parts: head = glycerol, tails = fatty acid.

The fatty acids are chains of hydrocarbons.

Saturated : there are only single bonds b/w every C-C, this means no double bonds in the fatty acid tail. As it name suggests, the chain is saturated with H atoms hence it is heavily packed. They are solid at room temperature.

Unsaturated : they have a minimum of one double bonds b/w two carbons & due to this double bond, there is reduced space for the H to occupy. So the chain is less saturated with H atoms. The double bond forms a bend in the chain. Liquid at room temperature due to the bend.

2) Example : a stone thrown upwards vertically.

When the stone attains the top height, The entire kinetic energy gets converted into potential energy. The entire potential energy is converted into kinetic energy under free fall of stone.

3) Example : a compressed spring contains potential energy and when it is released it is converted into kinetic energy. Potential energy can be defined as the energy that is stored in something & kinetic energy can be defined as the energy due to motion.

4) Organic molecules are made up of C atoms in long chains/rings & atoms like H, O, N are linked to them. A molecule can be considered organic if it is having both hydrogen & carbon (there are exceptions such as HCN).

hope the answer helps.