Chemistry PS1 2 Atomic Structure

HS PS1-2 Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

THINKING ROUTINE

Choose one scientist involved in the discovery of aspects of atomic structure below. How does their discovery help you understand the structure of the atom? What other information did you need to fully understand atomic structure?

What did you know about atomic structure?

What do you know now?

What else do you want to know?

Aerospace CONNECTIONS:

Applications and examples

Periodic Table of AEROSPACE

See Applications and Examples Materials used in aerospace--compounds with different bond types in air and space artifacts

Monitoring CO Atmospheric research including CO NASA

Antarctic Meteorites and Mars Smithsonian NMNH

Science conneXions with Aerospace

1. Atomic structure

2. Periodic Table/ Periodicity

Periodic Table of Aerospace

3. Electromagnetic spectrum

The structure of atoms

Atoms are tiny: FIND OUT HOW TINY movie Ted Talk

Atoms have a a tiny, dense nucleus in the center--you saw how dense in the movie above.

The nucleus contains PROTONS (How many protons?) The number of protons in an atom = ATOMIC NUMBER of the element

Protons have a +1 charge and one proton is equal in mass to one neutron. Neutrons are also found in the nucleus (except in atoms of hydrogen-1)

But atoms are neutral--have no overall charge because there are equal numbers of negatively charged electrons in the atom compared to the number of protons

ELECTRONS move around (not really orbiting) the nucleus. How many electrons in an atom? The same as the number of protons--and equal to the atomic number of the element

Atom showing 4 electron shells:

More about the electromagnetic spectrum

CHANDRA X-ray Observatory and the Smithsonian

National Postage Stamp PD

#1

#2

#3a

#3b

Start with the shell closest to the nucleus--count the electrons --here 2 (fill inner shells first--maximum number of electrons in Shell 1 = 2)

Shell #2 has 8 electrons (maximum number of electrons in Shell 2 = 8)

Shell number 3 has 8 electrons (maximum number of electrons in Shell 3 = 8)

There are no electrons in Shell 4

For the electron arrangement: list the numbers in each shell, from Shell #1 outwards, with a comma between each

So electron arrangement = 2, 8, 8

[There are a total of 18 electrons so this is the electron configuration of element number 18, argon

FLAME TESTS

Check out the flame test lab using water and the significance of the electron transitions which produce the different colors

Heat elevates electrons to higher energy levels--energy is ABSORBED--"excited" electrons. When the energy is EMITTED, some energy wavelengths in the visible region. Different elements produce different colors because they have different electron energy level transitions:

E = hc

wavelength

h = Planck's constant

c = speed of light