Atoms

Question 1

What is an atom?

Answer 1

An atom is the smallest particle into which an element can be divided in and still be the same substance.

Question 2

What is an element?

Answer 2

An element is the simplest pure substance.

Question 3

What is a pure substance?

Answer 3

A pure substance is a substance that you can’t break down into other substances and still have the same chemical and physical properties.

Question 4

About how many total elements are there?

Answer 4

There only about 118 elements. EVERY SINGLE substance on earth is made up of same combination of these elements.

Question 5

How many atoms would it take to equal the thickness of a sheet of aluminum foil?

Answer 5

50,000!!!!

Question 6

What is a nucleus?

Answer 6

It contains protons and neutrons.

Question 7

What is a electron cloud?

Answer 7

It’s the area outside of the nucleus that holds the electrons.

Question 8

Protons - the facts:

Answer 8

> subatomic particles
positively charged particles
All protons are exactly like all other protons (a proton from a gold atom is the same as a proton from a Nitrogen atom)

Question 9

Neutrons - the facts:

Answer 9

> subatomic particles
> Located inside the nucleus
> all neutrons are exactly like all other neutrons
> neutrons have NO electric charge
> neutrons are neutral

Question 10

Electrons - the facts:

Answer 10

> subatomic particles
located outside of the nucleus in the electron cloud
electrons are negatively charged

Question 11

What are shells?

Answer 11

They are different levels of energy called shells, where electrons are believed to orbit around the outside of the nucleus of the atom in the electron cloud.

Question 12

What can the number of protons determine?

Answer 12

It can determine what the element is.

Question 13

How do you know the amount of protons each atom has?

Answer 13

Since each element has its own element key, you can tell by checking the atomic number, which indicates the number of protons.

Question 14

How are the number of electrons and protons in an atom related?

Answer 14

In an atom, the number of electrons is the same as the number of protons.

Question 15

What is the term for an “Atomic Mass Unit”?

Answer 15

AMU

Question 16

What is the mass of one proton and one neutron?

Answer 16

The mass of one proton = 1 AMU

The mass of one neutron = 1 AMU

Question 17

How do you find the mass of the atom?

Answer 17

Add up the Protons and Neutrons

Since electrons are so tiny, they don’t get counted inn the mass

Question 18

How do you know the mass of an element?

Answer 18

Look at the mass number on the element key.

Question 19

Where are electrons located in?

Answer 19

They are located in shells or energy levels.

Question 20

Each sell can only hold a specific number of electrons
1st shell - \_\_\_ electrons
2nd shell -\_\_ electrons
3rd shell - \_\_\_ electrons
4th shell - \_\_\_\_ electrons

Answer 20

1st - 2
2nd - 8
3rd - 8
4th - 18

Question 21

Electrons shells are filled up starting in the shell ______.

Answer 21

closest to the nucleus

Question 22

Once that shell is full, then the ______ gets filled up and so on.

Answer 22

next shell

Question 23

What are valence electrons?

Answer 23

They are the electrons in the outermost shell.

Question 24

There can be no more than ___ valence electrons.

Answer 24

8

Question 25

What is the exception?

Answer 25

The exception is H and He because they only have 1 or 2 electrons so they are full at 2.

Question 26

Why are valence electrons important?

Answer 26

> They determine some of the chemical properties of the element
They are the only electros involved inn chemical reactions.