Evolution of Atoms

Question 1

“Matter could not be divided indefinitely”

Answer 1

Democritus

Question 2

He named the smallest piece of matter “atomos” meaning “not to be cut” or “indivisible”

Answer 2

Democritus

Question 3

“Atoms were small, hard particles that were all made of the same material but were different shapes and sizes”

Answer 3

Democritus

Question 4

He believed that matter could be divided into smaller and smaller pieces forever

Answer 4

Aristotle

Question 5

He believed that matter was made of a combination of four elements: earth, fire, water, and air

Answer 5

Aristotle

Question 6

He proposed the hook and eye model (to account for chemical combination) based on experimentation and not on pure reason

Answer 6

John Dalton

Question 7

He proposed the atomic theory by studying gases

Answer 7

John Dalton

Question 8

He was the one who first proposed that atoms are divisible.

Answer 8

J.J. Thomson

Question 9

He found that atoms could sometimes eject a far smaller negative particle, the electron (1897) while working with a cathode ray tube.

Answer 9

J.J. Thomson

Question 10

He called the negatively charged particle “corpuscles”, today known as electrons

Answer 10

J.J. Thomson

Question 11

He developed the Plum Pudding model of an atom

Answer 11

J.J. Thomson

Question 12

TRUE or FALSE: The plums represented the negative electric charges (electrons), and the pudding as a shapeless mass of uniform positive electrification

Answer 12

True

Question 13

He introduced that the positive electrification mentioned by Thomson is a small dense center he named nucleus (1911)

Answer 13

Ernest Rutherford

Question 14

He is considered to be the father of nuclear physics.

Answer 14

Ernest Rutherford

Question 15

He also discovered the proton (1919)

Answer 15

Ernest Rutherford

Question 16

The Nuclear Model of Atom is made by

Answer 16

Ernest Rutherford

Question 17

This model is described wherein the atom contains a small, dense, positively-charged center (nucleus), with negative electrons orbiting a nucleus in set, predictable paths

Answer 17

The Nuclear Model of Atom

Question 18

A Danish scientist who proposed an improvement by placing each electron in a specific energy level.

Answer 18

Niels Bohr

Question 19

He also proposed that electrons can move up a level if given enough energy. He called this energy a quantum of an energy and the movement of electron a quantum leap.

Answer 19

Niels Bohr

Question 20

He proposed the Planetary Model of Atom

Answer 20

Niels Bohr

Question 21

According to him, electrons move in definite orbits around the nucleus much like planets circle the sun.

Answer 21

Niels Bohr

Question 22

An Austrian physicist who used mathematical equations to describe the likelihood of finding an electron in a certain position, with the help of Werner Heisenberhg

Answer 22

Erwin Schrodinger

Question 23

Erwin Schrodinger developed a model known as?

Answer 23

Electron cloud model, also called as Quantum mechanical model

Question 24

He introduced the concept of sub-energy levels (s, p, d, f)

Answer 24

Erwin Schrodinger

Question 25

This model can be portrayed as a nucleus surrounded by an electron cloud

Answer 25

Quantum Mechanical Model of Atom

Question 26

He discovered neutron in 1932 while experimenting on the radiation emitted by Beryllium

Answer 26

James Chadwick

Question 27

He also described that neutron is slightly heavier than proton and could penetrate much further into a target than protons

Answer 27

James Chadwick

Question 28

He was awarded a Nobel Prize in Physics in 1935 for his discovery of neutron

Answer 28

James Chadwick

Question 29

TRUE or FALSE: Neutron took longer time to be discovered because neutron has no charge.

Answer 29

True