Download Make a large atom with p:95, n:146, e:95 - TSDCurriculum

Atom Builder Simulation-1
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Name __________________________Per___
Open the simulation “Atom Builder” at http://www.camse.org/sims/builder/ (Uses Java – no iPad)
Use your periodic table to determine the number of protons in the elements.
A. GET TO KNOW THE SIMULATION (SIM):
1. DO: Use your periodic table and the SIM to build a neutral Lithium atom (same number of protons
as electrons), with one more neutron than proton. (Click on “New Atom” then enter the correct
number of protons, neutrons, and electrons, or drag spheres into the existing atom)
2. DO: Press the right arrow at the bottom of the simulation
how your atom reacts with other atoms in the real world.
(near the words “new atom”) to see
a. Move the atom around with right and left arrow keys on your keyboard.
b. Move it close to other atoms (red clouds and blue clouds). Can it touch these other atoms?
Do the red or blue atoms (clouds) attract or repel your atom?
3. DO: Press the left arrow at the bottom of the SIM to go back to the atom building screen. Change
the atom into a positive ion with charge 2+, then return to the testing screen.
4. DO and WRITE: Read the questions and watch the ion to find the answers. If your ion changes,
return to the atom building screen and reset your atom to 3 protons, 4 neutrons, and 1 electron.
a. What color is the positive ion you built?
b. How does your positive ion interact with the other positive (red) and negative (blue) ions in
the testing world?
B. ISOTOPES
5. READ: This simulation only lets you to build atoms that exist in nature or have been made by
scientists. If you can’t build it, it can't be made in the real world.
Scientists use the word isotope to distinguish between atoms that have the same number of
protons but different numbers of neutrons. The prefix is "iso" means "same" and they should have
used "prot" for protons. The new word would have been "iso-prot". Instead they wrote "iso-tope".
Isotopes are "atoms of the same element (same number of protons) but with different nuclei due
to the different numbers of neutrons”. Scientists name isotopes using the mass number (the total
number of protons plus neutrons in the nucleus). An atom with 8 protons and 8 neutrons is called
"Oxygen - 16", or 16O for short. The 16 in 16O is a superscript on the left side of the element symbol.
You can also write
"O-16 ".
6. DO and WRITE: 16O is one of the isotopes of oxygen.
a. Write the name (with mass number) of three other isotopes of Oxygen (Use the simulation
to find out which are buildable.)
16O,
Modified from camse
_________________ , _________________ , _________________ ,
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7. (Think and discuss, then write an answer.) All of the chemical properties of elements are linked to
their electrons, so you can't do any chemical tests to detect different isotopes. What kind of
laboratory tests might detect the different isotopes of the same type of atom? (Hint: think about
mass number)
C. STABLE AND UNSTABLE ATOMS
8. READ: Some combinations of protons and neutrons are stable and some are unstable. In this
simulation you can only TEST atoms that are stable.
9. DO: You found that a Lithium isotope with 3 protons and 4 neutrons was testable.
a. Now build a Lithium isotope with 5 neutrons and press the arrow to test it. What
happened?
b. Try to explain why this happened (Use words from #10).
D. WHAT ABOUT BIG ATOMS? Do and Write.
10. Go back to the builder, and make a Barium atom (symbol = Ba, 56 protons). You can select “New
Atom” and type in the number of protons, neutrons, and electrons. Write the numbers below.
Barium atom
p: 56
n:
e:
11. What is the smallest number of neutrons Ba can have in nature (buildable)? What is the largest
number? The easiest way to do this is to build a new atom and type a small number of neutrons.
Repeat with a large number of neutrons. The program will automatically reset to the min or max.
Barium minimum n:
maximum n:
12. Test your Barium atom and find out which isotopes are allowed in testing. To do this quickly,
reset to the Barium minimum n and test, then reset to the Barium maximum n and test (it will
change to something testable). Which isotopes of Barium are stable?
13. Small atoms are stable when the number of neutrons is approximately equal to the number of
protons (n  p). Those atoms had up to 8 protons. Does this relationship hold for Barium?
Read: When a nucleus has more than 50 protons, it is stable when n >p.
Later, you will find out why the Gnome only allows certain nuclei in the testing world.
Modified from camse
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