Periodic Table Notes 8 th gr. Physical Science

Objective Students will be able to use their periodic table to calculate the number of protons, neutrons, and electrons that an atom has. Students will also be able to predict the physical and chemical properties of an element using the periodic table.

Warm-up: Discuss with a partner what a proton, neutron and electron are.

Answer Protons, electrons and neutrons are the smaller particles that make up atoms (building blocks of nonliving things, elements, compounds)

Discuss The smallest particle of matter that has the characteristic of an element is called: a. A compound b. A molecule c. An atom d. An ion

C. An atom Atoms are the building blocks of nonliving things (elements, compounds, and mixtures)

True or false A bar of gold is made up of billions of gold atoms.

Atomic Number- the number of protons in an atom The number of protons in an atom is EQUAL to the number of electrons in an atom. So if an atom has an atomic number of 82… There are ______ protons There are ______ electrons

Atomic mass number- the sum of the number of protons and neutrons in the nucleus of an atom Number of neutrons = atomic mass – atomic number So if the atomic mass is 207 and the atomic number is 82, then there are _______ neutrons in the atom.

Modern periodic table- is arranged according to increasing atomic number and by physical and chemical properties. As you move from left to right on the PT, the number of protons increases by one.

If there is a modern periodic table does that mean that there was a previous periodic table?

Yes! How do you think the original periodic table was arranged? Why did it change?

Periods- are the horizontal rows on the table. The elements increase by one proton and one electron as you move from left to right.

Warm-up: What element will share similar physical and chemical properties with Bromine? a. Krypton b. Arsenic c. Chlorine d. Sulfur

Group aka Family- are the vertical columns that share similar chemical and physical properties to one another.

Group 1- Alkali metal family the most reactive metal family and are very reactive in water, soft, silvery grey, have one valence electron and react well with the Halogen family (group 17)

Reactive- the ability to chemically react with another element to form a compound.

Group 17- Halogen Family is the most reactive nonmetal family on the periodic table. The often form compounds with the Alkali metal family (group 1) They have 7 valence electrons

Discuss: Which element is the MOST reactive nonmetal? A: Fluorine- label it on your periodic table

Group 18- Noble gases Do not react to form compounds, they are inert All but Helium have 8 valence electrons