Atom
Element
Isotopes
Pure substance
Compound
Molecule
Chemical Bond
Ionic bond
Ion
Covalent bond / THE CHEMISTRY OF LIFE
- anything that has mass and takes up space.
- basic unit of matter.
contains subatomic particles:
proton: + charge, found in nucleus.
neutron: no charge, found in nucleus.
electron: - charge, orbits nucleus.
atoms are neutral: #protons = #electrons.
atomic number = #protons = identity of element
atomic mass = #protons + #neutrons.
- atoms of element with different # neutrons
radioactive isotopes
unstable nucleus breaks down and gives off energy = radiation.
uses: medical tracers, kill bacteria,
cancer treatment, etc.
- matter made up of 1 types of particle.
- formed by combination of 2 or more elements.
e.g. Na: explosive solid in water.
Cl: poisonous gas.
NaCl: table salt
- smallest particle of a compound.
tells # atoms of each element in compound.
- energy that holds atoms together in molecules.
- electrons are transferred from 1 atom to another.
- atom with charge.
if atom gains electrons (- charged ion).
- electrons are shared between atoms.
Water is important
Why??
Polar
Hydrogen bonds
Cohesion
Adhesion
capillary action
/ WATER: THE ELIXIR OF LIFE
- 75% of earth is water.
- 98% is in liquid state
- liquid, solid and gas found on earth
- life began in water.
- covalent bonds betw/ H and O atoms.
- O has slight – charge.
- H has slight + charge.
- O of one H2O attracts H of another H2O.
- H2O molecules “stick” to each other.
causes surface tension, droplet formation.
- wqter molecules “stick” to other substances.
- water moves in tiny tubes.
adhesion to another surface.
- e.g plants, filter paper, paper towels.
“Universal” solvent
Hydrophilic
Hydrophobic
Solution
Suspension
Density
Heat /
- dissolves many other polar substances.
- “water loving” molecules like sugars dissolve in water.
- “water fearing” molecules like fats don’t dissolve.
- even mixture of 2 or more substances.
solute = substance with lesser amount.
- mixture of water and undissolved material.
- ice is less dense than liquid water.
- heats up and cools more slowly than surroundings.
pH scale
Acid
Base
Neutral
Buffers / Acids and Bases
- measurement system from pH 0-14.
- compound that forms H+ ions in solution.
pH below 7.
e.g. stomach acid, lemon juice, etc.
- compound that forms OH- ions in solution.
pH above 7.
e.g. bleach, detergents, etc.
- concentration H+ = concentration OH-.
- weak acids or bases that react with strong acids or bases to prevent sudden pH changes.
buffers in organisms to maintain pH.
Organic compounds
Why is carbon special?
Macromolecule
4 groups of macromolecules in living things.
Carbohydrates
monomer
function
/ Chemistry of Carbon
- contain carbon (CO2 is INORGANIC)
- has 4 valence electrons
- forms covalent bonds with many other elements
- can bond to other carbons
- can form millions of different compounds.
- large molecule made of smaller subunits.
polymer: chain of monomers bonded together.
polymerization: process of making polymer
from monomers.
- proteins, lipids, carbohydrates, nucleic acids.
- made of C, H, N, O, P, S
- made of C, H, O (1:2:1 ratio)
- made by plants
- monosaccharide = simple sugar
- polysaccharide = long chains of monosaccharides
- energy source and structure.
glycogen: short-term energy storage: animals
starch: short term energy storage: plants
cellulose: cell walls: plants (“fiber”)
Lipids
made of
function
Proteins
monomer
function
/
- made of C, H, O (mostly C, H )
- not soluble in water
- fatty acid (tails) and glycerol (backbone)
unsaturated fatty acid: 1 C=H bond.
- energy storage
e.g. lard, butter, etc.
unsaturated fat: long-term: plants
e.g. olive oil, canola oil, corn oil, etc.
- membranes
- steroids
e.g. hormones, cholesterol, etc.
- waxes: protective water-proof coverings.
plant leaves/fruit
insect exoskeletons
- also called: polypeptide chains.
- made of C, H, N, O S
- amino acid: amino group, carboxyl group, R group
- depends on shape and amino acid sequence.
enzymes: regulate reaction rates
immune system: fight disease
nutrient storage in cell:
chemical messengers
Nucleic acids
monomer
function
/
- stores genetic information, codes for proteins.
2 types: deoxyribonucleic acid (DNA)
ribonucleic acid (RNA)
- nucleotide (3 parts)
phosphate group
nitrogen base
- DNA: stores genetic information
- RNA: transmits code to build proteins
News flash!!
Chemical reaction
Reactants
Products
Chemical Equation / Chemical Reactions
- EVERY PROCESS IN LIVING THINGS INVOLVES CHEMICAL REACTIONS!!
- process that changes 1 set of chemicals into another set of chemicals.
compounds/elements entering into rxn.
compounds/elements produces by rxn.
HCl + NaOH H2O + NaCl
Energy in reactions
Exothermic rxn
Endothermic rxn
Activation energy
Reactions in living things /
- breaking/forming bonds releases/absorbs energy.
rxns that absorb energy: need energy to get started.
energy needed to get rxn started.
- living things need to absorb energy to survive.
plants get energy from sunlight.
Enzyme
Substrate
Active site
Product
How an enzyme works
Factors that affect enzyme /
- biological catalyst that speeds up chemical rxn.
- uniquely shaped protein that helps break or build molecules.
- reactant(s) that fit into enzyme’s active site.
- place on enzyme where reaction happens.
- result of reaction.
- substrate(s) fit into active site on enzyme.
- reaction occurs and products are released.
- reaction continues until substrate(s) are gone.
- enzyme is used and reused.
- heat/abnormal pH denature (changes shape) enzyme.