Chapter 10 - Atoms

Question 1

All matter consists of what?

Answer 1

Atoms

Question 2

Where are protons and neutrons found?

Answer 2

In the nucleus

Question 3

Where are electrons found?

Answer 3

Orbiting the nucleus in electron clouds

Question 4

State the charge of each subatomic particle: Proton, Neutron, Electron

Answer 4

Proton: Positive (+)
Neutron: No charge (0)
Electron: Negative (-)

Question 5

The atomic number is equal to the number of _____ in an atom

Answer 5

protons

Question 6

In an element that has no overall charge, the atomic number also helps you identify what? Why?

Answer 6

The number of electrons; the number of protons (+) and electrons (-) must equal to create no overall charge in the element. So if the atomic number is 5 in an element (5 protons), then the element also has 5 electrons.

Question 7

What is the mass number?

Answer 7

The sum of the numbers of protons and neutrons in the nucleus of an atom.

Question 8

What is the atomic mass of an element?

Answer 8

The number that averages all of the masses of isotopes of an element together.

Question 9

If O-10 takes up 50% of all Oxygen (O) atoms in nature and O-4 takes up 50% of all Oxygen (O) atoms in nature, than what is the atomic mass for oxygen?

Answer 9

10 * 50% = 5
4 * 50%. = 2
___________+__
7 atomic mass units (amu)

Question 10

The number after the hyphen in an atom (H-12) is the atom’s what?

Answer 10

Mass number

Question 11

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

Answer 11

Subtract the atomic number(# of protons) by the atomic number

Question 12

Element:Atomic Mass :: Atom:_____

Answer 12

Mass number

Question 13

What defines an element(no other element has the same ____)?

Answer 13

Its atomic number

Question 14

Two atoms have the same atomic number but a different number of neutrons(and therefore a different mass number). What are theses elements called?

Answer 14

Isotopes

Question 15

The electron is a lot (larger, smaller) than a proton or neutron

Answer 15

Smaller

Question 16

If an atom has more protons than electrons, then it is what?

Answer 16

A positively charged ion

Question 17

Describe gravitational force.

Answer 17

All objects attract each other. The larger the mass and the greater the distance between objects, the stronger the gravitational force.

Question 18

Describe electromagnetic force.

Answer 18

Objects with alike charges repel and objects with different charges attract.

Question 19

Describe strong force.

Answer 19

The close distance between the neutrons and protons in the nucleus of an atom causes strong force and keeps the nucleus together. Without the neutrons, there would be no buffer between the protons, causing them to repel each other.

Question 20

Describe weak force.

Answer 20

In some unstable atoms, neutrons have the ability to change electromagnetic charges; it can turn into a proton or electron. Weak force plays a key role in radioactive elements

Question 21

Who thought that you could keep cutting a particle infinitely?

Answer 21

Aristotle

Question 22

Who thought that you would end up with a particle that couldn’t be divided?

Answer 22

Democritus

Question 23

Who experimented with different substances and developed an atomic theory?

Answer 23

John Dalton

Question 24

Who found that atoms could be divided into further parts and discovered the electron of the atom? He also created the plum-pudding model.

Answer 24

J.J. Thomson

Question 25

Who used a gold-foil experiment to discover the small, dense nucleus of the atom?

Answer 25

Ernest Rutherford

Question 26

Atoms consist mostly of _____

Answer 26

Empty space?

Question 27

Who discovered that electrons can jump between certain paths, or energy levels?

Answer 27

Niels Bohr

Question 28

What are electron clouds?

Answer 28

Regions around the nucleus where electrons are likely to be found.

Question 29

Up to how many electrons can each energy level hold?

Answer 29

1st: 2 2nd: 8 3rd: 18

Question 30

Is it possible to have 1 electron on the first energy level, and 4 on the 2nd? Why or why not?

Answer 30

No; the 1st energy level must reach its maximum capacity (2)before electrons can go on the 2nd energy level.

Question 31

The outer energy level of an atom is called its _____ ,and the electrons on that outer shell are called_____.

Answer 31

Valence shell | Valence electrons

Question 32

The Lewis structure has dots around the atom's symbol. What do the dots represent?

Answer 32

Valence electrons

Question 33

The Octet rule states what?

Answer 33

That the goal of atoms is to have 8 electrons on its valence shell. An atom is more likely to gain electrons from another atom if the number of valence electrons is closer to 8.

Question 34

State Dalton's atomic theory (3 statements)

Answer 34

1. All substances are made of atoms, or small particles that cannot be created, divided, or destroyed. 2. Atoms of the same element are exactly alike, and atoms of different elements are different. 3. Atoms join with other atoms to make new substances

Question 35

If an atom has 5 protons in its nucleus and 7 electrons, it is what?

Answer 35

A negatively charge ion

Question 36

Describe the nucleus

Answer 36

Small, dense, and positively charged.

Question 37

Which subatomic particle is the smallest, and therefore has the least amount of mass?

Answer 37

Electron

Question 38

If an atom has the same amounts of protons and electrons, it is called a ______

Answer 38

Balanced atom

Question 39

If an atom has a mass number of 10 and an atomic number of 5, then how many neutrons are in the nucleus of this atom?

Answer 39

5 ((10 protons + neutrons) - 5 protons = 5 neutrons)

Question 40

What is an atom?

Answer 40

The smallest particle of an element that can't be divided

Question 41

Electrons are likely to be found where?

Answer 41

In the electron clouds

Question 42

Who discovered the electron, which proved that atoms can be further divided into smaller parts?

Answer 42

J.J. Thompson

Question 43

The discovery of the _____ proved that atoms can be further divided into smaller parts.

Answer 43

Electron

Question 44

If an balanced element has an atomic number of 7, how many valence electrons are there?

Answer 44

``` 1st shell - 2 2nd shell (Valence shell ) - 5 ```

Question 45

An atom with 15 electrons will have how many dots on its Lewis Structure?

Answer 45

1st shell: 2 2nd shell: 8 3rd shell (valence shell): 5 5 dots