In fact, all organisms depend on chemicals & chemical reactions. The Venus flytrap eats animals to get nutrients that it needs to make molecules such as proteins. Other chemicals made by the plant's cells enable the Venus flytrap to digest the animals that it eats. In fact, all organisms depend on chemicals & chemical reactions.

Biology – the study of life Before we begin to study biology, we need to understand what life is made of & the processes that make life possible.

Introduction to Biochemistry The Chemistry of Life

What do a frog, a skyscraper, a car, & your body all have in common?

Matter Anything that has mass & takes up space

What is matter made of? Atoms: basic unit of matter Make up all things on Earth

It would take you more than a trillion years to count the number of atoms in a single grain of sand!

Atoms Composed of: Protons: positive (+) charge Electrons: negative (-) charge Neutrons: neutral, no charge

Protons & Neutrons Located in the nucleus Have a mass of 1 amu (atomic mass unit)

Electrons Located around the nucleus in electron clouds (not actually rings!) Have a negligible mass, because they are hundreds of times smaller than protons & neutrons

Atoms The number of protons indicates the type of atom! Carbon Nitrogen Oxygen

Elements Pure substances made up of one type of atom All atoms of that element look the same, with the same number of protons, neutrons (average), & electrons.

Reading the Period Table of Elements Letters: symbol for the element, representation Atomic Number: number of protons in the atom Atomic Mass: mass of the nucleus, (# protons + # neutrons)

This gives the element a neutral charge. # electrons = # protons The number of protons is the same as the number of electrons. This gives the element a neutral charge.

How many electrons are in Cobalt? 58 59 27 31

How many neutrons are in Cobalt? 27 59 25 32

What element is this? Helium Potassium Nitrogen Carbon

Ions Ions are charged atoms that have gained or lost electrons to become more stable.

Bonding An attraction between atoms or molecules Ionic Bonds Covalent Bonds Hydrogen Bonds

Ionic Bonds Electrons are transferred between atoms NaCl (sodium chloride), CaS (calcium sulfide) Strong force Between a metal and nonmetal What would cause this?

What happens to atoms that are oppositely charged? Ions Formed when atoms gain or lose electrons Positive Ions Negative Ions Na becomes Na+ & Cl becomes Cl-. What happens to atoms that are oppositely charged?

Ionic bonds form between oppositely charged ions.

Covalent Bonds Actually share electrons between atoms CO2 (carbon dioxide), CH4 (methane) Strong force Between 2 nonmetals

Hydrogen Bonds Form between water molecules Very weak force

Molecules 2 or more atoms bonded together O2, CO2, H2O

The properties of a molecule are very different than the properties of the elements that make up the molecule. Atomic oxygen (O1) doesn’t exist on Earth for very long, but it exists in space. The oxygen we breathe is O2.

The properties of a molecule are very different than the properties of the elements that make up the molecule. A diamond is pure carbon, but carbon can also form sugars, proteins, & other molecules.

All compounds are molecules, but not all molecules are compounds! A type of molecule with at least 2 different types of atoms H2O, CO2 All compounds are molecules, but not all molecules are compounds!

Reading & Writing Molecular Formulas Subscripts: written below the level of the line Signify the number of atoms in the molecule 1 Mg atom + 2 Cl atoms  MgCl2

How many of each type of atom? Al(NO3)3 1 Al 3 N 9 O (CH3)3CH 4 C 10 H

Reading & Writing Molecular Formulas Coefficients: written to the left of the molecule Signify the number of molecules 5NaCl  5 molecules of NaCl

2C6H12O6 – 2 Glucose Molecules How many total molecules? 2 molecules of C6H12O6 How many total atoms? 12 C + 24 H + 12 O = 48 total atoms C6H12O6 – Glucose 2C6H12O6 – 2 Glucose Molecules

Counting Atoms Practice Qs Substance Element 1 Element 2 Element 3 1 CaCO3 Ca = 1 C = 1 O = 3 2 2CaSO4 Ca = 2 S = 2 O = 8 3 __Na2CO3 Na = 4 C = 2 O = 6 4 __SiO2 Si = 2 O = 4