
Objectives: Students will...
state the location, charge, and mass of protons, neutrons, and electrons.
determine the number of protons, neutrons, electrons, mass number, and charge of an atom or ion.
interpret or construct an atomic symbol to describe an atom or ion.
use the number of protons, neutrons, and electrons to draw a model of an atom or ion, identify the element, and determine the mass and charge.
Part 1: Atom Screen
Directions: Click on the 'Atom' Screen in the simulation below. Answer questions 1-6.
Take three minutes to interact with the simulation. Write three observations you have about the simulation.
Which subatomic particle determines an atom's identity?
Determine the charge, mass, and location of each subatomic particle in the atom.
mass number = 1
in the orbits (orbitals)
Neutral (0) charge
Positive (+) charge
in the nucleus (center)
mass number = 0
Negative (-) charge
proton
neutron
electron
Which of the following best describes how to calculate the mass number of an atom?
Which of the following best explains what an ion is?
Complete the table
Part 2: Symbol Screen
Directions: Click on the 'Symbol' screen at the bottom of the simulation, then answer questions 11-12.
Click on the Symbol screen and interact with the simulation. Write three observations you have from the 'Symbol' screen.
Let's figure out the important parts of an atomic symbol.
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Using the symbol above, identify:
how the value of each letter is determined
what the letter represents.
represents: charge
represents: element symbol
represents: atomic number
represents: mass number
determined by: (# of protons) + (# of neutrons)
determined by: (# of protons) - (# of electrons)
determined by: # of protons
a
b
c
d
Part 3: Game Screen
The moment you've been waiting for! Click on the 'Game' Screen at the bottom of the simulation. Spend some time playing each of the four games.
Add your score for each game to the picture below.
Match the sentences below with the words that best go in the blanks.
| Stavka koja se može prevući | arrow_right_alt | Odgovarajuća stavka |
|---|---|---|
Protons and neutrons are ____ than electrons. | arrow_right_alt | atoms |
There is mostly ____ between electrons. | arrow_right_alt | nucleus |
The center part of an atom is called the ____. | arrow_right_alt | protons |
All matter is composed of tiny particles called ____. | arrow_right_alt | outside of |
Elecrons are found ____ the nucleus. | arrow_right_alt | empty space |
A nucleus is made up of neutrons and ____. | arrow_right_alt | more massive |
Use the periodic table below to answer questions 13-15. Note: the number above each element symbol is the element's atomic number.

A calcium (Ca) atom has a mass number of 42. How many neutrons are in the atom?
An oxygen ion with a charge of -2 has eight electrons.
Match the following atom/ion descriptions with the element
| Stavka koja se može prevući | arrow_right_alt | Odgovarajuća stavka |
|---|---|---|
An atom with 36 protons and 36 electrons | arrow_right_alt | Tc (Technetium) |
An ion with 36 electrons and a charge of -1 | arrow_right_alt | Fe (Iron) |
An atom with 43 protons | arrow_right_alt | Br (Bromine) |
An atom with 24 neutrons and a mass number of 50 | arrow_right_alt | V (Vanadium) |
At atom with 23 protons and a mass number of 43 | arrow_right_alt | Cr (Chromium) |
An atom with a neutral charge and 24 electrons | arrow_right_alt | Kr (Krypton) |
Use the periodic table to fill out the table below. Assume all atoms are neutrally charged (i.e., they are not ions!)

What numbers did you write in the colored boxes in question 16? Match your answers below!
| Stavka koja se može prevući | arrow_right_alt | Odgovarajuća stavka |
|---|---|---|
Green
| arrow_right_alt | 53 |
Blue
| arrow_right_alt | 20 |
Orange
| arrow_right_alt | 13 |
Pink
| arrow_right_alt | 64 |
Purple
| arrow_right_alt | 5 |
Use the periodic table to fill out the table below.

What numbers did you write in the colored boxes in question 18? Match your answers below!
| Stavka koja se može prevući | arrow_right_alt | Odgovarajuća stavka |
|---|---|---|
Pink
| arrow_right_alt | 10 |
Purple
| arrow_right_alt | 11 |
Orange
| arrow_right_alt | +3 |
Green
| arrow_right_alt | 36 |
Blue
| arrow_right_alt | +1 |