Atom Builder
Name_________________________
Date ___________ Period _________
Before even picking up a computer . . .
Look at a Periodic Table and find Beryllium (Be)
A. How many protons are in a neutral Beryllium atom? _____________
B. How many neutrons are in a neutral Beryllium atom? ________________
C. How many electrons are in a neutral Beryllium atom? ______________
Look at a Periodic Table and find Nitrogen (N). how many . . .
D. protons? ____________ neutrons? ____________ electrons? ____________
Online:
http://phet.colorado.edu/en/simulation/build-an-atom
Choose ‘Build an Atom’
1. Click the three green “+” signs on the right hand side of the screen to open the boxes.
2. Check out the simulation.
a) What would the X in the middle of the circles represent? ___________________
b) What part of the atoms would be represented by the circles? ________________
c) Drag one proton to the circles and let go. In what part of the atom does it end up?
What happens to the net charge?
What happens to the mass?
d) Drag one neutron to the circles and let go. In what part of the atom does it end up?
What happens to the net charge?
What happens to the mass?
e) Drag one electron to the circles and let go. In what part of the atom does it end up?
What happens to the net charge?
What happens to the mass?
How many electrons can be put on the inner circle? _________ outer circle? _________
f) In order to get the name of the atoms to change, what particle needs to be changed?
3. Based on the information you wrote for A-C above, build a Beryllium atom.
a) Make sure it says ‘stable’ near the nucleus and Neutral Atom at the top right of the
electron orbitals.
b) A valence electron are the electrons in the outer ring (or energy level). How many
valence electrons does Beryllium have? _____________
c) What happens to the charge when you remove an electron?
d) What are charged atoms called? (top right) ______________
e) Remove one neutron.
f) What is the n ew mass of Beryllium? ______________
Click “Reset All,”
4. Based on the information you wrote for D above, build a Nitrogen atom.
a) You should have added electrons until it says ‘neutral atom’
b) How many valence electrons does Nitrogen have? ____________
c) How do the number of electrons compare to the protons?
While you still have the nitrogen atom built, click on Symbol at the bottom and familiarize yourself
with what each number means by moving particles in an out. (mass, protons, charge)
Describe . . .
1) What happens when you change the number of protons?
2) What happens when you change the number of neutrons?
3) What happens when you change the number of electrons?
BEFORE DOING ANYTHING ELSE . . . answer the following
a. Which particle gives an atom its identity? ________________________
b. Where is this particle located? ____________________
c. In the simulation, which color is this particle? ______________
d. For an atom to be neutral which particles need to be the same?
e. When an atom has a charge, the number of which two particles will be uneven?
f.
What’s a charged particle called? ___________
g. When there are more _____________ than ______________ the charge will be _____
h. When there are more _____________ than ______________ the charge will be _____
i.
Which particles give an atom its mass? _______________ and _________________
Try each game. Call me over when complete with at least 3 stars, and I will check it off.