THE ATOM The smallest particle of any material.

1. THE ATOMThe smallest particle of any material.

2. “Protons, Electrons & Neutrons Oh My” • The atom is made up of three subatomic particles • The Proton • The Electron • The Neutron Each particle has a specific charge and location with in an atom.

3. The Always Positive Proton • Protons are positively charged subatomic particles. • They are located in the nucleus of an atom. • The symbol for the proton p+. +

4. The Neutron • Neutrons are neutral subatomic particles, that means they have no charge. • They are also located in the Nucleus. • The Symbol for the Neutron is “n”.

5. The Always Negative Electron • Electrons are negatively charged subatomic particles. • Their symbol is “e-”. • Their location orbiting around the nucleus. -

6. ISOTOPES • Some atoms have more neutrons then they have protons. These atoms are called Isotopes. • They do not effect the way an atom reacts with other atoms.

7. The Next Level • Electrons do not all stay inside one tight space like the Protons or Neutrons. • They orbit in 3D clouds called shells

8. Filling the Gaps • Electrons are distributed in shells of increasing energy levels, where the lowest energy shells are filled first.

9. The levels • Each shell can be represented by a single ring or orbital. This orbital is the total number of electrons possible for that energy level. • First ring holds 2e- • Second ring holds 8e- • Third ring holds 18e- • Fourth ring holds 32e-

10. The Shells Broken Down When we break each electron orbital down into its shells we see that really only 2 e- can fit into each shell. Once an orbital has the maximum number of electrons it can hold, you fill the next level.

11. Periodic Table • You can use the periodic table to figure out the number of protons and electrons an atom has.

12. Each Element • An element is matter made up of only one type atom. • Each element has a specific number of electrons, protons and neutrons.

13. Atomic Number • The atomic Number will always be at the top. • It represents the number of protons that element has.

14. Atomic Mass • The quantity of matter in the atom. • Remember that most of an atom is made up of protons and Nuetrons.

15. Balance • We will need to know how many electrons are in each atom for the element. Elements like to balanced. That means there are the same number of electrons as there are protons.

16. Nuetrons • To find the number of Nuetrons simply round the atomic mass to the nearest whole number and then subtract from the atomic number.

17. Periodic Law Modern tables are arranged by the atomic number (the number of protons). When arranged this way elements with similar properties line up or are close to each other. This is called Periodic Law.

18. Periods • Each row of the periodic table is a period. • Elements in the same period have the same number of atomic orbitals.

19. Groups • Each column is called a Group. • Each element in a group has the same number of electrons in the outer orbital.

20. Families • Certain elements may have similar physical properties and act the same even if they have different orbital shells and different numbers of protons, these are families.

21. The Stable Atom • Atoms like to be stable. • Only when an atom’s outer orbital is filled is it stable. • Atoms will combine or react with each other to become stable.

22. “Molecules” • When two different atoms combine they form a molecule. • For example if we combine two Hydrogen Atoms with one Oxygen Atom what molecule do we get?

23. Compounds Put those molecules together and you have a compound. A compound is any substance that is made up of two or more atoms bonded together.

24. Types of Bonds • A chemical bond is when two atoms join their electrons. • There are four main types of bonds. • Ionic Bonds • Metallic Bonds • Covalent Bonds • Hydrogen Bonds

25. Ionic Bonds • Some atoms are able to fill their outer orbital by giving up or gaining an electron. • In other words STEALING!

26. Ionic bonds • When an atom gives up an electron the atom has more protons then electrons and becomes positively charged. • When an atom gains an electron the atom has more electrons than protons and becomes negatively charged.

27. Ions • An atom that loses an electron has a positive charge, we call these CATIONS. • An atom that gains an electron has a negative charge, we call these ANIONS.

28. Ionic Compounds • Positively charged atoms are attracted to negatively charged atoms. • When they come together they form an ionic compound.

29. Metallic Bonds When metal atoms bond they each kick out an electron. These electrons can float freely around each atom. Since the atoms are now positively charged they are attracted to the sea of electrons and are bonded.

30. Covalent Bonding • Some times atoms can share electrons to fill their outer orbital. • Sharing = covalent bond

31. Hydrogen Bonds When hydrogens combine with other atoms the Hydrogens stay slightly positive and the other atom stays slightly negative. This is called polarity.

32. Hydrogen Bonds When two polar molecules come together the weakly positive hydrogen will be attracted to the weakly negative other atom. This is called a Hydrogen Bond. Water is the best example.