Scientist/ Atomic Theory

Question 1

Aristotle named atoms atoms

Answer 1

False/

Question 2

Who proposed that matter was composed of tiny indivisible particles?

Answer 2

Democritus

Question 3

Aristotle was a Greek philosophers thought that matter was composed of four elements: air, earth, fire, and water

Answer 3

True

Question 4

Which scientist described a positively charged core (“nucleus”) in the middle of a lot of empty space?

Answer 4

Rutherford

Question 5

Which scientist described an atom made of a solid positively charged substance with electrons dispersed throughout it?

Answer 5

Thomson

Question 6

Which scientist described the existence of the neutron?
(neutral particles in the nucleus of an atom)

Answer 6

Chadwick

Question 7

J. J. Thomson’s plum pudding model of the atom addressed the issue of why

Answer 7

electrons are electrically charged.

Question 8

Rutherford expected alpha particle to travel almost straight through a target of gold fol. The results of his gold foil experiment did not support

Answer 8

Thomson’s plum pudding theory

Question 9

James Chadwick showed that the nucleus also contained a neutral subatomic particle known as the

Answer 9

Neutron

Question 10

(Billiard Ball Model)
_______ states that an atom is a uniform, solid sphere

Answer 10

John Dalton

Question 11

Atoms are indivisible and indestructible

Answer 11

John Dalton

Question 12

Atoms of the same element are identical

Answer 12

John Dalton

Question 13

Atoms of different elements combine in simple proportions or ratios to create a compound

Answer 13

John Dalton

Question 14

(Discovered radioactivity)
__________ stated that spontaneous emission of radiation from the nucleus

Answer 14

Henri Becquerel

Question 15

States that’s there are three types of Decays:
- alpha (a) - positive
- beta (B) - negative
- gamma (Y) - neutral

Answer 15

Henri Becquerel

Question 16

(Cathode Ray Tube Experiments)
__________ states there’s beam of negative particles

Answer 16

J. J. Thomson

Question 17

(Discovered Electron)
- negative particles within the atom

Answer 17

J. J. Thomson

Question 18

(Discovered the nucleus) (gold foil experiment)
- dense, positive charge in the center of the atom

Answer 18

Ernest Rutherford

Question 19

(Nuclear Model)
- dense, positive nucleus surrounded by negative electrons

Answer 19

Ernest Rutherford

Question 20

(Bright-Line Spectrum)
-tried to explain presence of specific colors in hydrogen’s spectrum

Answer 20

Niels Bohr

Question 21

•(Joliot-Curie Experiments)
- Radiation bombardment produces a “new” particle

Answer 21

James Chadwick

Question 22

Nature has two forces - conflict and harmony

Answer 22

Aristotle

Question 23

________ claimed that each of the elements move naturally to their “proper place,” where it will be “at rest”

Answer 23

Aristotle

Question 24

Aristotle believed there was a fifth element called “ether” which solely comprised the heavens

Answer 24

True

Question 25

Who claimed chem was a mixture of science and mysticism

Answer 25

Alchemy

Question 26

All matter is made of tiny pieces

Answer 26

Democritus and J Daltion

Question 27

Matter is composed of atoms, which move through empty space

Answer 27

Democritus

Question 28

An atom cannot be divided

Answer 28

Democritus and Daltion

Question 29

An atom cannot be created

Answer 29

Democritus and J Daltion

Question 30

An atom cannot be destroyed

Answer 30

Democritus and J J Daltion

Question 31

Different atoms combine in whole number ratios to form compounds

Answer 31

J Daltion

Question 32

The properties of atoms vary based on the shape, size and movement

Answer 32

Democritus

Question 33

Different kinds of atoms come in different sizes and shapes

Answer 33

Democritus

Question 34

Who originally proposed the concept that matter is composed of tiny, indivisible particles?

Answer 34

Democritus

Question 35

Whose work is credited with being the beginning of modern atomic theory?

Answer 35

John Dalton

Question 36

Explain why Democritus was unable to experimentally verify his ideas.

Answer 36

He lacked the tools necessary to demonstrate the existence of atoms

Question 37

What was Aristotle’s objection to the atomic theory?

Answer 37

There was no empty space therefore atoms cannot move through space

Question 38

State the main points of Dalton’s atomic theory using your own words. Which parts of Dalton’s theory were later found to be erronous? Explain why.

Answer 38

One of Dalton’s atomic theory’s state that an atom is the smallest particle in a chemical reaction , Substance are made of atoms, an atom can’t be destroyed or made, & diffrent atom elements can be mixed. Later an it was found that atomes are not the smalest particles becuse they can be divided into electrons, neutrons, & Protons. And it’s also false that diffrent atom elements can be mixed, Some compounds will turn into gas or vapor.

Question 39

Explain why atoms are electrically neutral.

Answer 39

The (+) charge of the nucleus balances the (-) charge of electrons leaving the atom equal, no change on the atom

Question 40

Cathode-Ray Tubes Which subatomic particle was discovered by researchers working with cathode-ray tubes?

Answer 40

Electron were a beam of negative particles by J J Thomason

Question 41

Briefly explain how Rutherford discovered the nucleus.

Answer 41

By an experiment to prove that atoms were made up of just empty space so (+) charge particles would flow through a golden foil, but the alpha (+) scattered, it proved that there was a core in the atom (nuclear charge)

Question 42

What caused the deflection of the alpha particles in Rutherford’s gold foil experiment?

Answer 42

The dense core in the nucleus/(+) charges