What is Chemistry? Chemistry is the study of matter
What is matter? Matter is anything that occupies space and has mass.
Why do we need to study chemistry in a biology class? All living things are made up of matter, share the chemical building blocks, and depend on chemical processes for Survival.
What are the chemical building blocks? Elements Compounds Atoms
What are elements? An element is a pure substance that cannot be broken down into other substances by chemical means. Periodic Table- is a list of around 100 elements that are found on earth.
Who can give some examples of elements? Gold Sodium Helium
About 25 elements are essential to life Oxygen (O), Carbon (C), Hydrogen (H), & Nitrogen (N) make up about 96% of the living matter in your body
Important Element Symbols: H (Hydrogen) Cl (Chlorine) N (Nitrogen) Ca (Calcium) O (Oxygen) K (Potassium) C (Carbon) Na (Sodium) Each element is represented by a symbol made up of one or two letters. ** Note: If a symbol is two letters, only the first letter is capitalized
What are compounds? + Cl Salt Compound- is a substance containing two or more elements that are chemically combined in a fixed ratio. A compound’s properties may differ greatly from those of its component elements.
What is an atom? Atom- is the smallest possible particle of an element. Gold A piece of gold, is made up of only one type of atom (gold atoms)…Billions of gold atoms
Atoms P N Nucleus (protons and neutrons) Electrons
What are atoms made up of? Protons- subatomic particles with a positive electrical charge (+) Electrons- subatomic particles with a negative electrical charge (-) Neutrons- subatomic particles that are electrically neutral. An element’s physical and chemical properties depend on the number and arrangement of these particles.
When atoms bond together they are called…… MOLECULES Join
Bonds store energy Bond must be broken to release energy When is energy released?
Chemistry Shorthand: Formulas CO 2 A chemical formula represents the chemical makeup of a compound or molecule. How many carbon atoms in 1 molecule of CO2? How many oxygen atoms in 1 molecule of CO2? 1 2
Structural Formula Structural formula shows the kinds, numbers, and the arrangements of atoms. It also shows the bonds Bonds
How do we write chemical compounds/molecules using symbols? What is H 2 0? How many hydrogen atoms in 1 molecule of water? 2 How many oxygen atoms in 1 molecule of water? 1
Chemical Equations and Reactions A + B C or C A + B Reactants Products
Example of a Chemical Reaction: C 6 H 12 O 6 + O 2 6H 2 O + 6CO 2 GlucoseOxygenWater Carbon dioxide - Which are the reactants? - Which are the products? - How many water molecules are produced? - How many glucose molecules are used? - How many carbon atoms are present in a molecule of glucose?