lecture 3 Water and Life

These flashcards cover key vocabulary and concepts related to the role of water in life as discussed in the lecture.

Water

A liquid that is essential for all living organisms, making up 70-95% of cells.

Cohesion

The property of water molecules to stick to each other due to hydrogen bonding.

Adhesion

The property of water molecules to stick to other substances.

Hydrogen Bond

A weak bond formed between a hydrogen atom and an electronegative atom like oxygen or nitrogen.

Specific Heat

The amount of heat required to raise the temperature of 1 gram of a substance by 1°C, which is high for water.

Heat of Vaporization

The quantity of heat a liquid must absorb for 1 gram of it to be converted from liquid to gas.

Solvent

The dissolving agent of a solution, with water being the most versatile solvent.

pH Scale

A logarithmic scale used to specify the acidity or basicity of an aqueous solution.

Acid

A substance that increases the concentration of hydrogen ions [H+] in a solution.

Base

A substance that decreases the concentration of hydrogen ions [H+] in a solution.

Buffers

Substances that minimize changes in the concentration of H+ and OH- in a solution.

Hydration Shell

The sphere of water molecules around a solute particle.

Emergent Properties of Water

Properties that arise from the interactions of water molecules, including cohesion, adhesion, temperature moderation, expansion upon freezing, and solvent versatility.