Physical Science 101

Atom the basic building block of all matter one single “unit” of an element Examples: a Hydrogen atom, a Nitrogen atom

Elements contain one or more of the same type of atom! Atoms Elements contain one or more of the same type of atom! Examples include: Hydrogen – 1 proton per atom Carbon – 6 protons per atom Oxygen – 8 protons per atom Copper – 29 protons per atom Gold – 79 protons per atom

Element substance that consists of one or more of the same type of atom most common form (compared to atom), not easy to isolate one atom Periodic Table of Elements

Molecule smallest unit of a compound more than one atom chemically combined examples: Glucose – C6H12O6 (6 atoms of carbon, twelve atoms of hydrogen atoms and 6 atoms of oxygen) water (H₂O), breathable oxygen (O₂), and salt (NaCl)

contains more than one molecule of the same type of molecule Compounds contains more than one molecule of the same type of molecule Example of organic compound (a compound with carbon atoms): C6H12O6 – several molecules of glucose Example of inorganic compound (a compound with no carbon atoms): Water – several molecules of H₂O

Mixture when two or more things are combined physically, not chemically things within a mixture can be physically separated

Atoms Atoms have: A nucleus small, heavy part of the atom An electron cloud large, lightweight part of the atom Nucleus Electron Cloud

Atom Structure Neutron -1 Electron Proton +1 +1 -1

Nucleus of an Atom Nucleus contains: Protons Have a positive charge N All atoms are distinguished by the number of protons it has (atomic number) N N Neutrons Notice that protons and neutrons are same size, because have same mass. Have no charge (neutral) Have same mass as protons

Electron Cloud of an Atom An electron cloud contains: Electrons e- have a negative charge orbit the nucleus of the atom have a very small mass compared to protons and neutrons

Element Guide Proton Number-tells what element it is. - # of protons (also the atomic number) 2 He Explains name of the element. 4 Explains the total atomic weight-The number of protons PLUS the number of neutrons (round to the nearest whole number).

A chemical formula can be very informative. It shows the numbers and types of elements in a compound. What is the formula of the compound described by these compositions? One copper to one oxygen CuO One carbon to two oxygen CO2 One calcium to one carbon to three oxygen CaCO3 Hydrogen and oxygen in the ratio 2:1 H2O Carbon and hydrogen in the ratio 1:4 CH4 Potassium, nitrogen and oxygen in the ratio 1:1:3 KNO3

1. In an element, the atoms are all the same. Element or compound? True or false? 1. In an element, the atoms are all the same. 2. A compound contains atoms of different elements that form multiple, similar molecules. 3. Carbon is a compound. 4. Elements in a compound are easy to separate. 5. A chemical formula shows what elements (atoms) are in a molecule. TRUE FALSE

4. Substances in mixtures are not chemically joined. Mixtures – true or false? True or false? 1. Substances in a mixture are easier to separate than substances in a compound. 2. Pure water is a mixture. 3. Pure air is a mixture. 4. Substances in mixtures are not chemically joined. 5. Pure carbon dioxide is a mixture. TRUE FALSE

Subatomic Particle Breakdown Take out your agenda book and find the Periodic Table of Elements. Use your notes and work with your buddy: How many protons, neutrons, and electrons are in Carbon (C)?

(protons and electrons are equal in stable atoms – all for 8th grade) Carbon Protons – 6 Electrons – 6 (protons and electrons are equal in stable atoms – all for 8th grade) How to find the neutrons? Atomic mass = (# protons) + (# neutrons) Atomic number = (# protons) Atomic mass – atomic number = # neutrons 12 – 6 = 6 neutrons

Try one more….. How many protons, neutrons, and electrons in Arsenic?

Arsenic Protons - 33 Electrons - 33 Neutrons – 42 ( did you round the atomic mass to 75?)

Using your notes, complete the Physical Science 101 packet Using your notes, complete the Physical Science 101 packet. Use your resources and show me what you know! Whatever you don’t finish in class is for homework.