Atoms missed concepts

​Atoms

Atoms are made of protons, electrons, and neutrons

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Protons are positive

Neutrons are neutral​

Electrons are negative ​

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• Protons and neutrons are in the nucleus

• Electrons are on the outside

Multiple Choice

The atomic mass is the

• number of protons and neutrons inside the nucleus

• number or electrons or protons

• number of protons, neutrons and electrons

Multiple Choice

If an atom has 3 electrons, how many protons does it have?

• 1
• 2
• 4
• 3

Multiple Choice

The positively charged particles of an atom are the ________.

• electrons
• protons
• neutrons
• protons & neutrons

​Valence Electrons are the electrons on the outermost edge

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Bohr models with 1 or 7 valence electrons are highly reactive

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Group 18 the noble gases are non- reactive ​

Multiple Choice

This is a Bohr Diagram of Aluminum. How many valence electrons does Aluminum have?

• 3

• 4

• 5

Multiple Choice

Valence electrons are: 

• Electrons farthest away from the nucleus
• Electrons closest to the nucleus
• Electrons that just come and go - they don't stay with the atom
• Electrons in the second shell

​Groups - go up and down there are 18

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Period go side to side there are 7 ​

​Elements that are in the same group have similar characteristics

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Elements in the same period have the same number of energy levels ​

Multiple Choice

A __________ goes up and down on the periodic table.

• Group

• Period

Multiple Choice

A _________ goes side to side on the periodic table.

• Group

• Period

Multiple Choice

What two elements are in the same Period?

• K - Potassium and Na - Sodium

• Li - Lithium and Mg - Magnesium

• B - Boron and C - Carbon

• Zn - Zinc and N - Nitrogen

Multiple Choice

Which two elements would have similar properties?

• Ar - Argon and Xe - Xenon

• Og - Oganesson and Lu - Lutetium

• He - Helium and Lu - Lutetium

• Ar - Argon and Se - Selenium

​Counting atoms

small numbers are subscripts they tell us the number of atoms ​

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Large numbers are coefficients they tell us the number of molecules

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You have to multiply the entire formula by the coefficient ​

Multiple Choice

How many atoms of Iron are in this compound?

• 1

• 2

• 3

• 4

Multiple Choice

How many atoms of oxygen are in

3Fe₂O₃

• 6

• 9

• 18

• 2