Chemistry Test

Question 1

John Dolton

Answer 1

Created the modern atomic theory

Question 2

Atomic Theory (5 points)

Answer 2

1. All elements are made up of tiny particles
2. Atoms of a given element are alike
3. Atoms of different elements are different
4. Chemical changes happen when atoms link up or separate
5. Atoms are not created or destroyed by chemical changes

Question 3

Indivisible

Answer 3

Can not be divided

An atom can not be divided no matter what

Question 4

Dmitri Mendeleyev

Answer 4

Created the periodic table

Question 5

Niels Bohr

Answer 5

Made the structure of toms which is still used today

Question 6

Atomic structure

Answer 6

Nucleons made of protons and neutrons

Electrons in shells around it

Question 7

Charge of protons?

Answer 7

Positive

Question 8

Charge of neutrons

Answer 8

Neutral

Question 9

Charge of electrons?

Answer 9

Negative

Question 10

What are the names of the shells in an electron

Answer 10

K shell
L shell
M shell

Question 11

How many electrons can each shell hold?

Answer 11

K shell - 2
L shell - 8
M shell - 18

Question 12

Atomic weight

Answer 12

# of protons + # of neutrons 
(Bigger number on periodic table)

Question 13

Atomic number

Answer 13

# of protons 
Or # of electrons 
(The number of protons and electrons are always equal in an atom which makes the charge of an atom NEUTRAL)

Question 14

Elements

Answer 14

Substances which contains only one kind of atom. Each element has unique properties (92 in nature but many man made)

Question 15

Periodic table - groups

Answer 15

Vertical Columns - tell us how many electrons are in the last shell (valence)

Question 16

Periodic table - periods

Answer 16

Horizontal columns

Tells us how many shells in each atom

Question 17

Compounds

Answer 17

2 or more atoms joined together chemically

Question 18

Molecule

Answer 18

Smallest piece of a compound which still has the properties of the substance (H2O is the smallest part of a water compound)

Question 19

Chemical Formula

Answer 19

When 2 or more atoms join together - they make a molecule that has its own name
Example- when a hydrogen atom bonds with 2 oxygen molecules its FORMULA becomes H2O

Question 20

Element form compounds. How?

Answer 20

Donate an electron or receives an electron. If they donate they become positive (they have less negative charges) and if they receive they become negative (they get an extra negative charge)

Question 21

Structure of an atom

Answer 21

Nucleus with Ps and Ns

Shells around it with Es

Question 22

Structure of compound

Answer 22

When they bond together and share electrons between the 2 atoms

Question 23

Democritus

Answer 23

Coined the name “atom”