The Building Blocks of Matter Atoms

Page
3

What do you notice about the number

of quarks in the neutron and proton?

Slide 15

Sub-Atomic Particles Weight Comparison (protons, neutrons, electrons)

Neutron = 1.6749286 x10-27 kg Proton = 1.6726231 x10-27 kg Electron = 9.1093897 x10-31 kg

1836 electrons = 1 proton

1839 electrons = 1 neutron

How do you think the mass of a neutron

compares to that of a proton?

1 neutron ≈ 1 proton

Slide 16

Sub-atomic Particles Size Comparison (protons, neutrons, electrons, & quarks)

+

+

+

+

-

-

-

-

-

-

-

-

+

Slide 17

Atomic Number

The number of protons in the nucleus of an atom

-

-

-

What would be the atomic number of this atom?

Slide 18

Mass Number

The total number of protons and neutrons in an atom’s nucleus

Expressed in Atomic Mass Units (amu)

Each proton or neutron has a mass of 1 amu

-

-

-

What would be the mass number of this atom?

+

 3

 4

3 protons + 4 neutrons = a mass number of 7 amu

Why did we not account for the electrons when calculating the mass number?

Slide 19

Building Atoms

Using the whiteboard and the proton, neutron, and electron pieces, build the following atoms, and determine their atomic and mass numbers.

Slide 20

Atom Builder

Using the interactive website link below, practice building atoms.

http://www.pbs.org/wgbh/aso/tryit/atom/

Using the classzone.com link below, click on the “Build an Atom” simulation and practice building atoms.

http://www.classzone.com/books/ml_sci_physical/page_build.cfm?id=resour_ch1&u=2##

Slide 21

FORCES IN THE ATOM

Gravitational Force

Electromagnetic Force

Strong Force

Weak Force

Slide 22

Gravitational Force

The force of attraction of objects due to their masses

The amount of gravity between objects depends on their masses and the distance between them

Do you think this force plays a significant

role in holding the atom together?

Slide 23

Electromagnetic Force

The force that results from the repulsion of like charges and the attraction of opposites