What is an atom?Catalyst1. What are the 3 subatomic particles?Proton, neutron, and electron 2. What are the charges associated with them? Positive (proton), Neutral (neutron), Negative (electron)3. Where are they found in the atom?Nucleus (proton and neutron), Electron cloud (electron)

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What is an atom?Learning Target (Reminder)LT #2: I can explain the different parts of an atom and where they are located.

*What is an atom Powerpoint*Atom animation http://web.visionlearning.com/custom/chemistry/animations/CHE1.3-an-atoms.shtml

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What is an atom?Subatomic Particles TableComplete the table below.

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What is an atom?Subatomic Particles TableAnswers: Copy/correct your answers.

What is an atom?Learning Target Self-AssessLT #2: Rate yourself on a 3, 2, 1 scale. 3 is “I really know this” and 1 is “I don’t really get it.” Hold up your 3, 2, 1 with your fingers.

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Atomic TheoryLearning Target #3LT #3: I can describe the different atomic theories and how they have developed over time. Brainpop Atomic Model:http://www.brainpop.com/science/matterandchemistry/atomicmodel/

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Atomic TheoryIndependent Reading p. 125Read p. 125-128 and fill out the following table:

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Atomic Theory Explanation/Description

Dalton’s Atomic Theory

Thomson’s Model

Rutherford’s Model

Bohr’s Model

Cloud Model

Modern Atomic Model

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Atomic Theory

Explanation/Description

Dalton’s Atomic Theory

All elements are composed of atoms that can’t be divided. Atoms of the same element are exactly alike and have the same mass.

Thomson’s Model

Found that atoms contain negatively charged particles and reasoned that there must be positively charged particles as well.

Rutherford’s Model

Through his experiment, discovered the nucleus of an atom and called the positively charged particles protons.

Bohr’s Model Added that the electron has specific orbits around the nucleus(like planets around the sun )to Rutherford’s model.

Cloud Model Electrons do NOT circle the nucleus like planets. Instead, they can be anywhere in a cloudlike region around the nucleus, depending on energy level (electron cloud).

Modern Atomic Model

Neutron discovered in 1930s. At the center of the atom is a tiny, massive nucleus containing protons and neutrons. Surrounding the nucleus is a cloudlike region of moving electrons.

Atomic TheoryLearning Target Self-AssessLT #3: Rate yourself on a 3, 2, 1 scale. 3 is “I really know this” and 1 is “I don’t really get it.” Hold up your 3, 2, 1 with your fingers.

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The Periodic TableLearning Target #4LT #4: I can read and understand the periodic table of elements and explain all the different sections. Brainpop Periodic Table:http://www.brainpop.com/science/matterandchemistry/periodictableofelements/

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The Periodic TableVocabulary and ReadingWrite the definitions of the following words, found on p. 129-137.Atomic numberIsotopesMass numberAtomic massPeriodic tablePeriodGroupChemical symbol

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The Periodic Table

Catalyst1. What are the periods on the periodic table? What are the groups?Periods are the horizontal rows and groups are the columns.

2. Define atomic number and atomic mass.Atomic number is the number of protons and atomic mass is the number of protons and neutrons.

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The Periodic TableLearning Target #4 (Reminder)LT #4: I can read and understand the periodic table of elements and explain all the different sections.

Now, please put everything away except a pencil and a separate sheet of paper.

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IV. The Periodic Table

A. The periodic table is table/chart in which the elements are arranged in the order of increasing atomic numbers.

B. The periodic table was developed by a Russian chemist named Dmitri Mendeleev.

C. Reading the periodic C. Reading the periodic tabletable

8 26

OOxygen

15.9994

Atomic number

Element symbol

Element name Atomic

mass

Number of Electrons in each shell

D. Using to periodic D. Using to periodic tabletable

• Always look at the key for each periodic table used.

1. Atomic number - is the number of protons and electrons for each atom. It is also the order in which the modern periodic table is set up.

2. . Atomic mass- is the sum of the protons and neutrons in an atom.

Quick Review!

1. Atomic Mass: Add what two things?2. Atomic Number: is the number of what two

things?

Quick Review!

1. Atomic Mass: Add what two things?

Protons + Neutrons = Atomic Mass(Remember: Pete and Ned from the Atoms family!)

2. Atomic Number: is the number of what two things?

Protons and Electrons (Remember: P.E.)

E. The Number of Neutrons in an Atom1. To find the number of neutrons in an

atom use the following formula:

Neutrons= Atomic Mass-Atomic Number

Ex. To find the number of neutrons in a Carbon atom you would subtract the

Atomic Mass (12) - Atomic number (6) this =

6 neutrons

Practice finding Practice finding neutrons!!!neutrons!!!

• Find the number of neutrons in the following elements:

1. (Lithium) Li= 2. (Sodium) Na= 3. (Potassium) K=

Practice finding neutronsPractice finding neutrons

• Find the number of neutrons in the following elements:– Li= 6.9(round to 7)-3= – Na= 22.9(round to23)-11=– K= 39.1(round to 39)-19=

Li= 4 neutrons

Na= 12 neutrons

K= 20 neutrons

Using the electron ringsUsing the electron rings

• Each ring has a set amount of electrons. You cannot over fill a ring but you can under fill a ring.

pn

2e

8e

18e 32e

P6n6

2e

Electron Ring Practice!!!Electron Ring Practice!!!

Find the electron rings of the following elements.

• Li• K

Hint: Find out how many electrons each element has first! (What can

you look at?...)

Electron Ring Practice!!!Electron Ring Practice!!!

Find the electron rings of the following elements.

• Li =Atomic # 3

• K=Atomic # 19

P3n4

2 1e

P19n20

2e 8e 9e

VI. Families and periodsVI. Families and periodsA. The number of rings and number of

electrons on the last ring of any given element determines it position on the period table.

B. Groups- vertical columns*Similar chemical properties

C. Each horizontal row on the periodic table is called a period. *Not alike, but have the same number of energy levels