The Atom Test

What is an element?

What is an element?

A pure form of matter that cannot be broken down into similar substances.

What is an atom?

The smallest part of a chemical element that can exist.

What are subatomic particles?

They are protons, neutrons, and electrons aka the parts that make up an atom.

What is the charge (+/=/-), symbol, and mass (x amu) of a proton?

Charge: Positive (+)
Symbol: P ⁺
Mass: 1 amu

What is the charge (+/=/-), symbol, and mass (x amu) of a neutron?

Charge: Neutral (0)
Symbol: n ⁰
Mass: 1 amu

What is the charge (+/=/-), symbol, and mass (x amu) of an electron?

Charge: Negative (-)
Symbol: e^-
Mass: 0 amu

What do all the number parts of the diagram correspond to?

1. Electron cloud

2. Nucleus

3. Neutron

4. Electron

5. Proton

What is an Isotope?

Atoms that have different numbers of neutrons and still have the same charge.

What is this arrow pointing to? And what does it tell us?

The Atomic number, it tells us the amount of protons.

What is this arrow pointing to? And what does it mean?

The Chemical symbol, it is a one or two letter abbreviation of the element. (The first letter is capitalized & the second letter is not)

What is this arrow pointing to?

The name of the element.

What is this arrow pointing to? And how do you calculate it?

The Atomic mass, the average mass of all the isotopes.

What is a mass number, and how do you find it?

The mass number is the total number of protons and neutrons in an atom. You find it by rounding the atomic mass to the nearest whole number.

How do you find the number of protons in an atom?

It is the same as the Atomic number.

How do you find the number of electrons in an atom (assuming it is a neutral atom)?

It is the same as the number of protons.

How do you find the number of neutrons in an atom?

You do the Mass number minus the Atomic number
(Mass # — Atomic #).

You have Periods, families, and Groups. Which ones apply to rows and which ones apply to columns?

Periods apply to rows ←→, Groups apply to columns ↑↓, & families apply to columns ↑↓.

What are all the families of the Periodic table from left to right?

Left:
- Alkali Metals Group
- Alkali Earth Metals Group
- Transition Metals
- Boron Group
- Carbon Group
- Nitrogen Group
- Oxygen Group
- Halogens
- Noble Gases
Right:

What groups belong to the Transition metals family?

Groups 3-12

What series are most reactive?

Alkali metals, alkaline earth metals, Actinides, lanthanides, metalloids, and halogens.

What series are most unreactive?

Noble gases

Which Atomic model is currently accepted and which model do we use?

The “electron cloud model” is currently accepted and we use the “Bohr-Rutherford” or “Bohr Diagram”.

What do you write in the center (nucleus) of a Bohr diagram? How how do you write it?

The number of protons and neutrons
X P⁺
X N⁰

What goes around the nucleus of a Bohr diagram?

Electron and electron shells.

What are the names of the shells going from closest to the nucleus to farthest from the nucleus?

K, L, M, N (Mnemonic: Kids Like Macaroni Noodles)

Which shells have the most energy (closest to the nucleus or furthest from the nucleus)?

The shells furthest from the nucleus.

How many electrons does each cell need in order to be full?

K: 2
L: 8
M: 8
N: 8

When drawing (plump) electrons on a Bohr diagram in which direction do you draw them?

Clockwise.

How many shells do 12 electrons need?

3

What are valence electrons?

Electrons are the electrons in the outermost shell of an atom.

What do valence electrons indicate?

The atom’s reactivity with other atoms (full shells are most stable)

Which atoms tend to “give” valence electrons, which atoms tend to take valence electrons, and why is that?

Atoms with an almost full outer shell tend to “take” valence electrons from atoms with an almost empty outer shell because atoms “prefer” to have a full outer shell so they “give” and “take” accordingly.

What do Lewis dot diagrams only show?

Valence electrons.

How do you draw a Lewis dot diagram?

You draw a plump dot for each valence electron going clockwise around the element symbol.

What is the trick for figuring out the number of valence electrons for elements 1-20?

The last number in the group number corresponds to the number of valence electrons for groups 1-2 & 13-18 except helium which only has two valence electrons.

What is the trick for figuring out the number of shells for elements 1-20?

The period number corresponds to the number of shells for groups 1-2 & 13-18.

What is the symbol and atomic number for silicon?

Symbol: Si
Atomic number: 14

What is the symbol and atomic number for potassium?

Symbol: K
Atomic number: 19

What is the symbol and atomic number for chlorine?

Symbol: Cl
Atomic number: 17

What is the symbol and atomic number for krypton?

Symbol: Kr
Atomic number: 36

What is the symbol and atomic number for magnesium?

Symbol: Mg
Atomic number: 12

What is the symbol and atomic number for beryllium?

Symbol: Be
Atomic number: 4

What is the symbol and atomic number for calcium?

Symbol: Ca
Atomic number: 20

What is the symbol and atomic number for carbon?

Symbol: C
Atomic number: 6

What is the symbol and atomic number for titanium?

Symbol: Ti
Atomic number: 22

What is the symbol and atomic number for zirconium?

Symbol: Zr
Atomic number: 40

What is the symbol and atomic number for fluorine?

Symbol: F
Atomic number: 9

What is the symbol and atomic number for aluminum?

Symbol: Al
Atomic number: 13