Unit 3

Question 1

Atomic mass #

Answer 1

Average # of isotopes found in nature.

Question 2

Atomic number

Answer 2

# of protons = # of electrons 
ONLY if atom is neutral (no charge)

Question 3

Mass #

Answer 3

Atomic mass # rounded to a whole #.

Protons + Neutrons

Question 4

Isotopes

Answer 4

Same element but w/ different # of neutrons

Question 5

Protons: P+

Answer 5

DNA of atom, NEVER CHANGES

Question 6

Electrons: E-

Answer 6

Form chemical bonds

Question 7

Neutrons: N^0

Answer 7

Rounded atomic mass # - atomic #

Question 8

Where are protons and neutrons located?

Answer 8

Protons and neutrons are located in the nucleus

Question 9

Where are electrons located?

Answer 9

Electrons are located outside the nucleus

Question 10

12
Isotopic Notation: C
6

Answer 10

12 - Mass #: protons + neutrons (always bigger)
C
6 - Atomic #: only protons (smaller)

Question 11

Isotopic Notation using -

Answer 11

Symbol - Mass #

Question 12

What has the smallest mass: proton, neutron, or electron?

Answer 12

Electron has the smallest mass

Question 13

Why is atomic mass usually not a whole #?

Answer 13

Because it accounts for both the relative abundance and the mass of each of the atom’s isotopes

Question 14

How can an atom be electrically neutral?

Answer 14

If protons = electrons

Question 15

Where does mass (g) come from?

Answer 15

Mass comes from protons + neutrons

Question 16

Where does volume/ space (mL) come from?

Answer 16

Volume/ space comes from electrons

Question 17

How to calculate atomic mass (2 steps)

Answer 17

1. Mass x Abundance (decimal) = product

2. Add up all products

Question 18

Ions

Answer 18

Atoms that carry an electric charge by gaining/losing 1+ electron.

Question 19

Gaining e- =

Answer 19

Gaining electrons (e-) = negative # (anion)

Question 20

Losing e- =

Answer 20

Losing electrons (e-) = positive # (cation)

Question 21

Octet Rule

Answer 21

Many atoms combine so that they each have 8 electrons in their valence shells.

Question 22

Cation

Answer 22

Positive ion, atom, or molecule that’s lost 1+ electrons

Question 23

Anion

Answer 23

Negative ion, atom, or molecule that’s gained 1+ electrons

Question 24

Polyatomic ion

Answer 24

A group of atoms (covalently bonded) that have a charge

Question 25

Electromagnetic Spectrum

Answer 25

Longer wavelength = lower energy | Shorter wavelength = higher energy

Question 26

Alpha radiation symbol, mass, charge

Answer 26

``` Symbol: 4 He 2 Mass: 4 (heavy) Charge: 2+ ```

Question 27

Beta radiation symbol, mass, and charge

Answer 27

``` Symbol: 0 B -1 Mass: light 1/1840 Charge: -1 ```

Question 28

Gamma radiation symbol, mass, and charge

Answer 28

``` Symbol: 0 B 0 Mass: 0 none Charge: 0 ```

Question 29

Alpha beta gamma radiation atomic mass trend

Answer 29

Opposite change

Question 30

Alpha ray charge

Answer 30

Helium nucleus, 2+ charge

Question 31

Beta Ray charge

Answer 31

Electron, 1- charge

Question 32

Gamma photon ray charge

Answer 32

No charge

Question 33

Alpha penetration

Answer 33

Low: can't penetrate paper, clothing, skin

Question 34

Beta penetration

Answer 34

Medium: can't penetrate wood

Question 35

Gamma penetration

Answer 35

High, can't penetrate lead, can penetrate concrete

Question 36

Half life

Answer 36

Time taken for radioactivity of a specified isotope to fall -> 1/2 original value

Question 37

Calculating half life

Answer 37

Total time/ half life time= # of half lives

Question 38

Half life practice: How much of a 100g sample of Au-198 is left after 8.1 days if it's half life is 2.7 days?

Answer 38

12.5 g

Question 39

Calculating amount of remaining isotope

Answer 39

Amount remaining = og amount | x (1/2)^# of half lives

Question 40

Mass/ atomic # change trend for radioactivity

Answer 40

Opposite

Question 41

Organic compound

Answer 41

C = organic | Doesn't include CO, CO2, or CO3

Question 42

Oxidation Number

Answer 42

The charge that atom would have if the compound was composed of ions.