Discovery of an Atom (important people)

Question 1

what is an element?

Answer 1

simpilest form of matter

Question 2

what are atoms?

Answer 2

smallest unit of an element which maintains all the properties of that element

Question 3

most of an atom is ____________

Answer 3

empty space

Question 4

what is the nucleus made up of & what charge does it have

Answer 4

positive charge, protons and neutrons

Question 5

where do electrons exist? (3)

Answer 5

clouds, orbitals, energy levels

Question 6

Mass of a proton, neutron, and electron & what is the unit its measured in?

Answer 6

proton- 1
neutron- 1
electron- “0”
atomic mass units

Question 7

Elements are made of extremely small particles called atoms

Answer 7

John Dalton

Question 8

discovered electron, charge and mass

Answer 8

JJ thomson

Question 9

“Plum pudding”

solid substances with electrons sprinkled through out

Answer 9

JJ Thomson

Question 10

Atoms of a given element are identical in size, mass, and other properties (Not always mass)

Answer 10

John Dalton

Question 11

Atoms can be subdivided

Answer 11

JJ Thomson

Question 12

Atoms cannot be subdivided, created, or destroyed (can be subdivided)

Answer 12

John Dalton

Question 13

Discovered nucleus/proton, its charge and mass

Answer 13

Ernest Rutherford

Question 14

Atoms of different elements combine simple whole number ratios to form chemical compounds

Answer 14

John Dalton

Question 15

In chemical reactions, atoms are combined, separated, or rearranged

Answer 15

John Dalton

Question 16

Proposed a tiny positive nucleus in the middle and empty space with electrons on the outside

Answer 16

Ernest Rutherford

Question 17

discovered Bohr model of the atom; electrons move within certain energy levels/orbit around the nucleus

Answer 17

Niels Bohr

Question 18

Discovered neutron; its charge and mass

Answer 18

James Chadwick

Question 19

Added neutrons to the nucleus

Answer 19

James Chadwick

Question 20

Discovered light can act as a particle (has matter) and a wave (energy)

Answer 20

Vincent de Brogile and Erwin Schrodinger

Question 21

Explained random movements of the electrons/ ability to move energy levels

Answer 21

Vincent de Brogile and Erwin Schrodinger

Question 22

Who gave us our current “electron cloud model”?

Answer 22

Vincent de Brogile and Erwin Schrodinger

Question 23

what is energy?

Answer 23

the ability to do work

Question 24

difference between a wave and particle

Answer 24

particle is matter & wave is energy