Section 2.1
An atom is the smallest basic unit of matter
What are atoms found in/what do they make up? Turn and Talk What are atoms found in/what do they make up?
The center of the atom is called the Nucleus. Structure The center of the atom is called the Nucleus. It is made of protons (+ charged particles) and neutrons (no charge parts)
In a cloud around the nucleus are negatively charged particles called electrons. The difference in atoms comes in the numbers of protons electrons and Neutrons.
Protons = the atomic number of an atom The number of protons +the number of neutrons= Atomic Mass (Weight)
Answer in notebook If an atom has a proton number 6 and a neutron number 6, what is the atomic mass?
Think about it…. And answer in notebook If an atom has an atomic mass of 15 and a neutron number of 8, What is the number of protons?
Elements Elements are one particular type of atom that can not be broken down into simpler substances
Isotopes are atoms that have different numbers of neutrons. Scientists refer to isotopes by their name and the number of protons and neutrons they have. For example: carbon 12, 13 or 14
An ion is an atom that has lost or gained electrons (charged) Ionic Bond: Force between oppositely charged atoms Covalent Bond: When atoms share a pair of electrons
If an atom has lost 2 electrons, what will the charge of the atom be? Turn and Talk If an atom has lost 2 electrons, what will the charge of the atom be?
A compound is a subtance made up of atoms of different elements bonded together in a certain ratio.
A molecule is two or more atoms held together by covalent bonds.
Just checking to be sure your with me…. All molecules are compounds and all compounds are molecules. True or False Explain!
Electrons travel around the nucleus in regions called energy levels. Each level has a particular capacity Each level grows in capacity as they go up.
The levels 1st= 2 2nd= 8 3rd= 18
Answer in notebook. If an atom has 16 electrons, how will they be placed in each energy level?