A pure substance composed of two or more atoms.
The smallest particle of any element.
Particles that make up atom. They include:
Subatomic particle in the nucleus of an atom that has a positive charge.
Subatomic particle in the nucleus of the atom that has a neutral charge.
Subatomic particles orbiting around the nucleus of an atom that has a negative charge.
Where is most of the mass of the atom found?
In the nucleus because the protons and neutrons are the heaviest part of the atoms.
What subatomic particle has the least mass?
Nucleus of an atom?
The centre part of the atom.
Term given to the electric charge on the nucleus. It is found by counting the number of protons. It will always be a positive number since protons have a positive charge.
An atom whose overall charge in neutral. It has an equal number of protons and electrons.
What is atomic number?
Atomic number = number of protons = number of electrons in a neutral atom.
Where can the number of protons (atomic number) be found on the periodic table?
It is the number found in the left hand corner for each element.
What is the name of a row in the periodic table?
Period. The rows are numbered from 1 to 7.
What is the name of a column in the periodic table?
Group or Family. The families are also numbered1 to 18. Each family in the period table has similar properties.
What is the group and period number for Magnesium in the periodic table?
Group 2 period 3
Where are Metals found on the periodic table?
On the left side and the middle of the periodic table.
Where are non-metals found on the periodic table.
On the upper right corner of the periodic table.
Where are the metalloids on the periodic table?
Form a stair case toward the right side of the periodic table.
What are some family names in the periodic table?
Alkaline earth metals
What are the alkali metals?
Group 1 in the periodic table (excluding hydrogen). the are very reactive metals
What are the alkaline earth metals?
Group 2 in the periodic table. The are somewhat reactive metals.
What are the Halogens?
They are group 17 in the periodic table. The are very reactive non-metals.
What are the noble gases?
They are group 18 in the periodic table. They are very unreactive gaseous non-metals.
When an atom gains or loses an electron is becomes charged and is called an ion.
What charge does an atom become if it gains electrons.
Becomes a negative ion.
What charge does an atom become if it loses electrons?
It becomes a positive ion?
What is a Cation?
A positive ion. many metals become cations because they lose electrons.
What is an Anion?
A negative ion. Many non-metal ions become anions because they gain electrons.
How do you figure out the charge on an atom when it becomes an ion?
There is a number the periodic table that has a + or - beside it that tells you the charge of the ion. For example Aluminum will lose 3 electrons and become an atom with a charge of 3+ (Al 3+). Look at the periodic table.
Some metals are multivalent, which means they can form ions in more than one way depending on the chemical reaction. For example Titanium (Ti) can form a Ti4+ ion or a Ti3+ ion.
What is a Bohr diagram?
A Bohr diagram is a diagram that shows the number of electrons in each shell surrounding the nucleus of an atom.
How many electrons can fit in the first 3 shells of a Bohr diagram?
2 electrons, 8 electrons, 8 electrons.
How can you use the periodic table to find out the number of electron shells that surround the nucleus of an atom?
The period number (row number) of an element equals the number of shells in the atom. For example Hydrogen is in row 1, so it has 1 shell. Sodium is in row 3 so it has 3 shells.
What is a stable octet?
When the outermost shell of an atom has 8 electrons. It is said to be stable because it does not need to gain