Soph Sci Ch. 4

Question 1

the smallest particle of an element that retains the identity in a chemical reaction

Answer 1

Atom

Question 2

Greek philosopher who said atoms were indivisible and indestructible

Answer 2

Democritus

Question 3

Who discovered Electrons

Answer 3

Thompson

Question 4

Electrons were discovered using a ________

Answer 4

Cathode Ray

Question 5

In the experiment that discovered electrons the beam of light was attracted to a _________ charged plate and repelled by a ________ charged plate

Answer 5

positive, negative

Question 6

Who discovered the charge of an electron

Answer 6

Millikan

Question 7

Who suspended oil droplets between oppositely charged plates and studied their rate of fall

Answer 7

Millikan

Question 8

Who discovered the nucleus and protons

Answer 8

Rutherford

Question 9

Rutherford concluded the atom was mostly _________space with a __________ charged dense are called the _________

Answer 9

empty, positively, nucleus

Question 10

Who shot a beam of alpha particles into gold foil expecting the alpha particles to pass through or have a slight deflect

Answer 10

Rutherford

Question 11

Who discovered neutrons

Answer 11

Chadwick

Question 12

Who shot a beam of alpha particles a beryllium foil, which produced a radiation that was neutrally charged and had the same mass as protons

Answer 12

Chadwick

Question 13

the number of protons in the nucleus of an atom

Answer 13

Atomic Number

Question 14

The number of protons ________ the number of electrons in a neutral atom

Answer 14

equals

Question 15

the total number of protons and neutrons in an atom

Answer 15

Mass Number

Question 16

The number of _________ in an atom is the difference between the mass number and the atomic number

Answer 16

neutrons

Question 17

Mass number is the

Answer 17

superscript

Question 18

atoms that have the same number of protons but different numbers of neutrons

Answer 18

Isotopes

Question 19

Isotopes are chemically alike but have different ________

Answer 19

Mass Numbers

Question 20

is one twelfth of the mass of a carbon-12 atom

Answer 20

Atomic Mass Unit

Question 21

Atomic Mass Unit is one twelfth of the mass of a ________ atom

Answer 21

carbon-12

Question 22

is the weighted average mass of the atoms in a naturally occurring sample of the element

Answer 22

Atomic mass

Question 23

What do you need to know to calculate the atomic mass

Answer 23

Number of stable isotopes & Mass of each isotope & The natural percent abundance of each isotope

Question 24

Atomic number is the

Answer 24

subscript

Question 25

How do you find the neutrons in a element

Answer 25

Mass number- atomic number