Environmental Chemistry 9

What are cells made out of?

• 72% water

• 25% carbon compounds (carbohydrates, lipids, proteins, and nucleic acids)

• 3% salts (Na, Cl, K…)

What is organic chemistry?

The study of carbon compounds

• CO2 is not an organic compound

What are carbon atoms so important?

they are versatile building blocks as they have:

• 4 stable valence electrons

and can form:

• 4 single bonds

• 2 double bonds

• triple bond

• single bond

What is a polar covalent bond?

when the electronegativity difference between atoms is higher than 0.5

• the more electronegative atom pulls the electrons towards them and hogs it

What is a non-polar covalent bond?

when the electronegativity difference between atoms is less than 0.5

• the electrons are shared pretty evenly

What are hydrocarbons?

combinations of hydrogen and carbon

• non-polar

• hydrophobic

• stable

• source of energy

• not soluble in water

• can grow and gain complexity

What are macromolecules?

smaller organic molecules joined together to form larger molecules

What are the 4 major classes of macromolecules?

• carbohydrates (carbon, hydrogen, oxygen)

• lipids

• proteins

• nucleic acids

What are carbohydrates?

Made up of carbon, hydrogen, and water

Function

• energy, energy storage, raw and structural materials

Monomers

• ex. sugars, starches,

• Monosaccharides - simple single monomer sugars (ex. glucose)

• Polysaccharides - large polymers, many sugar molecules (ex. starch)