11/1/11 A/B DayLEQ: How can we determine the structure of an atom using the periodic table?

1. What is an atom? 2. What are the three particles (or parts) that atoms are made of?3. What is the difference between a proton and a neutron?4. What is the difference between a proton and an electron?5. What particles make up the nucleus of an atom?

Today’s LEQ:How can we determine the structure of an atom using the periodic table?

By the end of today, you should be able to…

1. Calculate the number of neutrons in an atom

2. Use the periodic table to draw models of atoms

3. Distinguish valence electrons

LET’S REVIEW!

Activating Strategy:

FOCUS VOCABULARY:

50. Atomic Number51. Atomic Mass52. Element53. Energy Level

EXPLAIN TO A 3rd Grader:How would we solve this word problem?

Together, Juan and Jordan have a total of 48 cookies. Juan has 25 cookies.

How many cookies does Jordan have? TOTAL: 48 cookiesJuan: 25 cookies

Jordan has 23 cookies

7

NNitrogen

14.01

Element Symbol

Atomic Number(# of protons

in the nucleus)

Element NameAtomic Mass

(total # of

particles

in the nucleus)

COPY THIS IN YOUR NOTEBOOK!

What two particles make up the nucleus?!

7

NNitrogen

14.01

Atomic Number(# of protons

in the nucleus)

Atomic Mass

(total # of

particles

in the nucleus)

How can we determine the total number of neutrons in the nucleus?!

Copy this in your notes!

Atomic Mass (Rounded)Atomic Number# of Neutrons

Below .5 Round DOWNAbove .5 Round UP

Let’s try it…. 1

HHydrogen

1.008

Atomic Mass: Rounded At. Mass: Atomic Number:

110

1.00811

Number of Protons: Number of Neutrons:

10

HYDROGEN:

Let’s try it…. 4

BeBeryllium

9.012

Atomic Mass: Rounded At. Mass: Atomic Number:

945

9.01294

Number of Protons: Number of Neutrons:

45

Determining Atomic Structure:

How we tell the… # of Protons:

# of Neutrons:

# of Electrons:

HOT Q: Atoms like to have a total charge of 0 (or neutral).

Knowing that atoms have both positive and negative particles

(protons and electrons), how can they have a total charge of 0?

THEY HAVE AN EQUAL NUMBER OF PROTONS

AND ELECTRONS!

In NORMAL ATOMS….

# of protons = # of electronsLet’s practice:Boron: Helium:Carbon:

4 electrons

2 electrons

6 electrons

Periodic Table: Independent Practice

Pg. R58 and R59 (back of the book!)

Why the weird shape?!

Helium

Sodium

Carbon

Energy Levels: hold electrons with the same amount of energy

1st Energy Level

2nd

3rd

DRAW THIS IN YOUR NOTES!

Drawing Electrons and Energy Levels: Helium

Protons: Neutrons:Electrons:

222

WHAT NUMBER ROW IS IT IN?! 1

Drawing Electrons and Energy Levels: BORON

Protons: Neutrons:Electrons:

565

WHAT NUMBER ROW IS IT IN?! 2

DRAW YOUR OWN!Pick THREE elements and draw models of each of them. You must choose ONE element from the first energy level, ONE from the second energy level, and ONE from the third energy level.

BE SURE TO:LABEL each element you drawDRAW “+” signs in your protonsINCLUDE the correct number of protons, neutrons, electronsDRAW electrons in their correct energy level

Summarizer:In 3-5 sentences, EXPLAIN how we can use the periodic table to determine the structure of an atom.

YOUR ANSWER MUST INCLUDE THESE WORDS:PROTON ATOMIC MASSNEUTRON ATOMIC NUMBERELECTRON ENERGY LEVEL