# Atoms and the Periodic Table L.E.Q. What is matter?

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Atoms and the Periodic Table L.E.Q. What is matter?

Atoms An atom is composed of ELECTRONS (negative charge) orbiting the outside of a nucleus. An atom is composed of ELECTRONS (negative charge) orbiting the outside of a nucleus. The nucleus is mad up of PROTONS (positive charge) and NEUTRONS (neutral charge). The nucleus is mad up of PROTONS (positive charge) and NEUTRONS (neutral charge). Electrons orbit the nucleus of an atom in an electron cloud. Electrons orbit the nucleus of an atom in an electron cloud.

Electron Clouds Electron clouds can be broken into 7 different energy levels. Electron clouds can be broken into 7 different energy levels. Each energy level can only hold a specific number of electrons. Each energy level can only hold a specific number of electrons. Each energy level must be filled before a higher energy level can have electrons. Each energy level must be filled before a higher energy level can have electrons.

Electron Cloud P N 2e 8e 18e 32e

Reading Information on Periodic Table 6 C Carbon 12.011 Electron Configuration Atomic Number Symbol Name Average Atomic Mass *Memorize* Atomic # = # of protons in the nucleus Atomic mass = # of protons + # of neutrons # of neutrons= Atomic mass- atomic number (# of protons) # of protons = # of electrons Electron Configuration = # of electrons in outer most energy level (shell). Why is the mass of carbon a decimal? 16 6A

Practice 3 Li Lithium 6.941 What is the atomic number of Li? How may electrons are in Li? What is the mass number? How many neutrons are in Li? How many electrons are in Li’s outer shell? Draw a Lithium Atom Look at the periodic table in your notes: What is the name of an element that has 47 protons? 1 1A

Lithium Atom Lithium has 3 protons and 3 electrons Lithium has 3 protons and 3 electrons Atomic Mass is 6.941, round to the nearest whole number (7) Atomic Mass is 6.941, round to the nearest whole number (7) Neutrons = Atomic Mass (7)-Atomic Number (3). There are 4 neutrons in a Lithium Atom Neutrons = Atomic Mass (7)-Atomic Number (3). There are 4 neutrons in a Lithium Atom +o+oo +o e ee