The Periodic Table• The Periodic Table gives us SO much

information about the world around us, but first you have to know how to read it!

Each of these little squares tells us about one specific

element.Reminder!: An Element is a pure

substance made of all the same type

of atom!

An Element

• Where an element is on the table can give you a lot of information about it.

• We are going to look at what information you can find out from each element’s square on the Periodic Table.

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This is what the square for Boron looks like.

An Element

• Find Boron on your periodic table.

• A basic periodic table will give you these four pieces of information about each element. We will go over each one and what they mean.

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Atomic Number• This is the Atomic

Number for Boron.

• The atomic number tells you how many protons and electrons an atom of Boron has. (So Boron has 5 protons and 5 electrons).

• The elements are also arranged on the Periodic Table so that the atomic numbers go in order.

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Reminder!: Protons and Electrons are in the nucleus of the atom. Protons carry a positive charge. Electrons carry a negative charge.

Chemical Symbol• This is the Chemical Symbol

for Boron.

• The chemical symbol is the same no matter what language you read the table in.

• Every element has a unique chemical symbol.

• The first letter is always capitalized. If there is a second letter, it is always lowercase.

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Chemical Name

• This is the Chemical Name.

• The chemical name may be different for a scientist viewing the table in a different language.

BBoron

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Atomic Mass• This is the Atomic

Mass of Boron.• Atomic mass is

measured in Atomic Mass Units (amu’s).

• It is the sum of the mass of all of the protons, neutrons, and electrons in one atom of Boron.

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Atomic Mass (continued)

• Electrons have very little mass. So little that they barely register in the atomic mass.

• For this reason, the atomic mass really only measures the mass of the protons + the neutrons.

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Atomic Mass (continued)

• Protons and Neutrons each weigh about 1 amu.

• Because they weight 1 amu and we know how many protons each atom has – it is easy to figure out how many neutrons each atom has.

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Reminder!: The Atomic Number tells you how many protons each atom has. Do you remember where the atomic number is?

NeutronsTo find the number of

neutrons:

1st – Round off the atomic mass to the nearest whole number

• 10.811 rounds to 11

2nd – Subtract the number of protons (the atomic number) from your new atomic mass

• 11 – 5 = 6

The answer is the number of neutrons the atom has!

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Neutron PracticeLet’s practice on a new

element!

• What is the atomic number for Fluorine?

• What is the atomic mass of Fluorine?

• What would you round the atomic mass too?

• __________ - ___________ = _________ (rounded atomic mass ) (atomic number)

(neutrons)

• How many neutrons does Fluorine have?

FFluorine

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