I. What is an atom?  Atoms are the basic unit of matter  All matter is made up of tiny atoms

Atom Atoms are the building blocks of all matter water MoleculeAtom O H H Subatomic

Subatomic Particles (Draw this) ProtonNeutronElectron Location in the Atom Mass Charge

Structure of an atom  There are 3 subatomic particles in an atom  Proton  Neutron  Electron

THE PROTON p+p+ Found in the nucleus Heavy: 1 amu Positive : +1

THE NEUTRON N°N°  Located in the nucleus. Heavy: 1 amu Neutral : 0 charge

o NUCLEUS: DENSE/HEAVY BUT TINY PART OF ATOM FOUND IN CENTER OF AN ATOM ½ Football Field Outer Edge of Atom Nucleus 50End Zone

Atomic Nucleus Summary  The nucleus is a dense area at the center of the atom  Protons and neutrons are found in the atomic nucleus

THE ELECTRON Found in the electron cloud Very light: 0 amu Negative: -1 charge e-e-

Electrons  Electrons have a relatively small mass compared to protons and neutrons  Electrons are found far away from the nucleus in an area called the electron cloud  Electrons have a negative charge

How small is an atom?  Atoms are TINY!  20 million hydrogen atoms would fit inside the period at the end of this sentence.  You are made of billions and billions of atoms 

Protons e-e- p+p+ N°N°  Neutrons Electrons Positive +1 Neutral 0 Negative

Nucleus is held together with nuclear energy Electron cloud is full of zipping electrons /watch?v=pV822HfqT44

Please complete the following table ProtonNeutronElectron Location in the Atom Mass Charge Nucleus Electron Cloud Heavy 1amu Heavy 1amu Very Light 1amu Positive +1 Neutral  0 Negative 

ATOMS HAVE A NEUTRAL CHARGE (most of the time……)  When we talk about the atoms of elements on the periodic table, we usually assume they have the same number of electrons as they do protons, giving the atom a neutral charge (+1 and -1 = 0 charge)  So if the atomic number of an atom is 8, how many electrons do we have?  Neutrally charged Atoms will have the same number of electrons as protons

How can I tell which atom is which element?  Every atom of an element has an ATOMIC SYMBOL- the letters representing the element Au, Ca etc. ATOMIC NUMBER – the number of protons + in an atom. Each element has a unique atomic number Example Carbon’s atomic number is 6, but Boron has an atomic number of 5 ATOMIC MASS – the number of protons + plus neutrons 0 in an atom. Example Carbon’s atomic number is 6, but its atomic mass is 12 6 protons and 6 neutrons

N0N0 P+P+ e-e- e-e- e-e- P+P+ P+P+ What is the atomic number of this atom? 3

Review of Atomic Structure  What is the basic unit of matter?  Atom  What are the 3 subatomic particles?  Proton, Neutron, Electron  What’s the electrical charge of a proton?  Positive (+)  What’s the electrical charge of a neutron?  Neutral  What’s the electrical charge of an electron?  Negative (-)

N0N0 P+P+ e-e- e-e- e-e- P+P+ P+P+ REMEMBER WHAT A PROPER ATOM LOOKS LIKE

Name something wrong with this atom 0

What is wrong with this atom? 00

What is wrong with this Atom?

Draw an atom CORRECTLY  2 protons, 1 neutron, 2 electrons