Starter Mrs. Rangel 9/9/ What does APE stand for? 2. What formula will help you find the number of neutrons in an atom? 3. find the number of protons, neutrons and electrons in an Argon atom. P= E= N= 4. Describe the charge of a proton, neutron and electron.

Argon P=18 E=18 N=22

Argon P=18 E=18 N=22 18 Ar Argon Atomic Number 40-18=22

 Matter is anything that takes up space and has mass.  All matter is made of atoms  Atoms are the building blocks of matter, sort of how bricks are the building blocks of houses.  Matter is anything that takes up space and has mass.  All matter is made of atoms  Atoms are the building blocks of matter, sort of how bricks are the building blocks of houses.

An atom refresher An atom has three parts: Proton = positive Neutron = no charge Electron = negative The proton & neutron are found in the center of the atom, a place called the nucleus. The electrons orbit the nucleus. Picture from

Bohr Model The Bohr Model shows all of the particles in the atom. Protons should have a (+) or P written on them. Neutrons should be blank or have an N. Electrons should have a minus sign (-) or an e. Created by G.Baker

Bohr Model Practice To know the number of protons, electrons and neutrons in an atom you only need to remember 2 things:

Bohr Model Practice 1. To know the number of protons, electrons and neutrons in an atom you only need to remember 2 things: 2. Mass # - Atomic # = Neutrons

Bohr Model Practice # of Protons and Electrons

Special rules for electrons…. You can’t just shove all of the electrons into the first orbit of an electron. Electrons live on shells or energy levels. Start on the energy level closest to the nucleus and work your way out Created by G.Baker

Nucleus 1 st energy level 2 nd energy level 3 rd energy level

 Now…let’s try some more in our journals!!

Magnesium P= E= N=

Magnesium P=12 E=12 N=12

Magnesium P=12 E=12 N=12 12 Mg 24.3 Magnesium Atomic Number 24-12=12

Which element has… 17 protons

Which element has… 17 protons Chlorine

Helium (He) How many… Protons Electrons Neutrons

What element is this? + ++

Lithium + ++

What element is this?

Boron

What element is this?

Carbon

Aluminum (Al) P= E= N=

Aluminum (Al) P= 13 N= 14 E=

Which element is this? P= 9 N= 10 E=

Fluorine (F) P= 9 N= 10 E=

1. What do you think the charge of the nucleus is? (positive, negative, or no charge) Explain in complete sentences!! 2. Have you ever experienced touching someone/something and got shocked? Elaborate on why you think it happened. application/connection

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