Atoms Basics
The smallest particle of an element that still has the properties of that element.
Atom
Protons have what type of charge?
Positive
A pure substance made of only one kind of atom.
Element
In 2CO₂, how many molecules of carbon dioxide are there?
2 (coefficient)
Electrons are located in the _______.
Shell/cloud
The center of the atom where most of its mass is found.
Nucleus
Which subatomic particle has almost no mass?
Electrons
What is formed when two or more atoms chemically combine?
Molecules
In 2CO₂, how many total carbon atoms are there?
2
What does the atomic mass of an atom represent?
The total number of protons + neutrons in the atom
What does the atomic number of an atom tell us?
How many Protons
Which two subatomic particles make up the atomic mass of an atom?
Protons + Neutrons
What is formed when two or more different atoms chemically combine?
Compounds
In 2CO₂, how many total oxygen atoms are there?
4
An atom of Aluminum has atomic number 13 and mass number 27. How many neutrons?
14 (27-13=14)
What are the 3 subatomic particles?
Protons, Neutrons and Electrons
Which two subatomic particles determine the charge of an atom?
Protons and Electrons
In the chemical formula 5H₂, is this a compound?
No - only 1 element
In 5H₂, how many hydrogen atoms are there?
10
An atom of Chlorine has atomic number 17 and mass number 35. How many neutrons?
18 (35-17=18)
An atom of Oxygen has an atomic number of 8 and a mass number of 16. How many neutrons does it have?
8 (16-8=8)
If an atom has 12 protons and 12 electrons, what is its overall charge?
Neutral
In the chemical formula 2CO₂, is this a compound?
Yes - 2 different types of elements
In 4H₂O, how many total atoms are there?
12
H = 8 (4x2=8)
O = 4 (1x4=4)
An atom has 20 protons, 20 neutrons, and 20 electrons.
What element is it?
What is its atomic number?
What is its mass number?
1. Calcium (Ca)
2. Atomic number = 20
3. Mass number = 40