CH. 3 (chapter 5 ap chem)

Question 0

Law of Definite Proportions

Answer 0

A given chemical compound always contains the SAME ELEMENTS in the EXACT same PROPORTIONS of mass

Question 1

The Law of Conservation of Mass

Answer 1

During a chemical reaction the total MASS of the PRODUCTS must be EQUAL to the TOTAL MASS of the REACTANT

Question 2

Law of Multiple Proportions

Answer 2

Whenever same two elements form more than one compound, the diff masses of one element COMBINE with the other mass of the other element are in a RATIO or SMALL WHOLE NUMBERS

Question 3

Dalton’s atomic theory

Answer 3

1. Elements are made up of tiny indivisible particles called atoms (nope, divisible..)
2. Atoms of the same elements are identical, different = different
3. Atoms of one element can combine with atoms of other elements in small whole # ratios to form compounds
4. Chemical reactions can be described as the separation, combination, or rearrangement of atoms

Question 4

Who is JJ Thomson?

Answer 4

He discovered the electrons using a cathode ray tube

Question 5

Who is Rutherford?

Answer 5

Discovered the nucleus by gold foil experiment

• dense & positively charged
• electrons outside nucleons

Question 6

The atom is mostly..

Answer 6

Empty space

Question 7

Atomic Number

Answer 7

of Protons

Question 8

Mass Number

Answer 8

Total number of protons and neutrons in the nucleus

Protons + neutrons

Question 9

Neutrons

Answer 9

Mass # - protons

Question 10

Electrons

Answer 10

Protons in a neutral atom

Question 11

Isotopes

Answer 11

Atoms of the same element that have the same number of protons but can have a different mass number (diff number of neutrons)

Question 12

Atom

Answer 12

the smallest particle of an element that retains the properties of that element

Question 13

Subatomic particles

Answer 13

1. Electron
2. Neutron
3. Proton

Question 14

Nucleus

Answer 14

small dense core of the atom which contains the positive charge and most of the mass

Question 15

Nuclear model of an atom

Answer 15

one in which the nucleus is composed of protons and neutrons, while electrons are distributed throughout the rest of the space

Question 16

Find the average atomic mass..

Ex) • chlorine-35: atomic mass = 34.969 amu
% abundance = 75.77%
• chlorine-37: atomic mass = 36.966 amu
% abundance = 24.23%

Answer 16

1) divide percentage by 100
2) time new percentage by mass number
0.7577 × 34.969 = 26.50 amu
0. 2423 × 36.966 = 8.957 amu
3) add the two new mass
26. 50 + 8.957 = 35.45 amu
4) the answer is 35.45

Question 17

Molar mass

Answer 17

The mass of one mole of representative particles of a substance

Question 18

The rays in a cathode tube are

Answer 18

Deflected away from a negative plate

Question 19

Most of the volume of an atom is occupied by the

Answer 19

Electrons

Question 20

Because a few particles bounced back from the foul, Rutherford concluded that they were

Answer 20

Repelled by densely packed regions of positive charge

Question 21

Cathode rays led to the discovery of

Answer 21

Electrons

Question 22

Who identified the nucleus

Answer 22

Rutherford

Question 23

Which part of Dalton’s theory has been modified

Answer 23

Atoms cannot be divided

Question 24

A what has no electrical charge

Answer 24

Neutron

Question 25

To find average atomic mass,

Answer 25

Make mass into small decimal (28.45--0.2845) multiply by percent add all together

Question 26

Bohr model

Answer 26

~Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus. ~With his model, Bohr explained how electrons could jump from one orbit to another only by emitting or absorbing energy in fixed quanta

Question 27

Charged particle

Answer 27

A particle with an electric charge

Question 28

Proton

Answer 28

a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge

Question 29

Where is the atoms volume located ?

Answer 29

The cloud of negatively charged electrons surrounding the nucleus

Question 30

The vast majority of an atom is what?

Answer 30

Empty space

Question 31

Ion

Answer 31

Electrically charged atom