ATOMIC THEORY

Question 1

stated that matter is composed on tiny indivisible particles called atoms

Answer 1

Democritus

Question 2

English school teacher who performed experiments to learn in what ratios different elements combine in chemical reactions

Answer 2

John Dalton

Question 3

Dalton’s Atomic Theory

Answer 3

1. All elements are composed of submicroscopic particles called atoms.
2. Atoms of the same element are identical.
3. Atoms of different elements can physically or chemically combine.
4. Chemical reaction occurs when atoms are separated, joined, or rearranged

Question 4

English physicist who discovered electrons in 1897 and proposed the model “plum pudding”

Answer 4

Sir JJ Thomson

Question 5

discovered the positively charged subatomic particles called protons

Answer 5

E. Goldstein

Question 6

English physicist who confirmed in 1932 the existence of another subatomic particle: neutron

Answer 6

Sir James Chadwick

Question 7

based on his discovery of the nucleus, he proposed the “Nuclear Atomic Model” in which electrons surround a dense nucleus

Answer 7

Ernest Rutherford

Question 8

young Danish physicist and a student of Rutherford proposed that the electrons are arranged in a concentric circular path, or orbits around the nucleus (Planetary Model)

Answer 8

Neils Bohr

Question 9

Austrian physicist proposed the “Quantum Mechanical Model” that shows the probability of finding electrons within a certain volume of space portrayed in a cloud

Answer 9

Erwin Schrodinger

Question 10

model of Thomson

Answer 10

Plum pudding model

Question 11

model of Rutherford

Answer 11

Nuclear model

Question 12

model of Neils Bohr

Answer 12

Planetary model

Question 13

model of Schrodinger

Answer 13

Quantum Mechanical model

Question 14

are assigned the values in order of increasing energy; n=1,2,3,4

Answer 14

Principal Energy Levels

Question 15

small massive structure located at the center of atom and carries a positive electrical charge

Answer 15

Nucleus

Question 16

the volume occupied by the electrons

Answer 16

Electron cloud

Question 17

equal to number of protons and electrons

Answer 17

Atomic number

Question 18

the relative weight of the atom of an element

Answer 18

Atomic weight

Question 19

the sum of the number of protons and electrons and is also equal to the atomic weight

Answer 19

Mass number

Question 20

atoms of a given element having the same atomic number but different atomic weights

Answer 20

Isotopes

Question 21

the orbits in which the electrons revolve designated by numbers 1, 2, 3, 4

Answer 21

Maini energy levels

Question 22

s p d f

Answer 22

sharp
principal
diffuse
fundamental

Question 23

region of space around a nucleus where an electron with a specific energy is most likely to be found

Answer 23

Orbital

Question 24

number of orbital per sublevel

Answer 24

s - 1
p - 3
d - 5
f - 7

Question 25

limits the number of electrons in any orbital to not more than two and this pair of electrons must be spinning in opposite direction

Answer 25

Pauli Exclusion Principle

Question 26

for a given sublevel, each orbital must be occupied by a single electron before pairing of electrons in any orbital of that sublevel to occur

Answer 26

Hund’s rule

Question 27

the distribution of electrons using this method indicates the energy level and sublevels that are filled

Answer 27

s p d f notation

Question 28

using arrows to represent electrons and boxes for orbitals

Answer 28

Rectangular Arrow Method

Question 29

nucleus is shown with its protons and neutron and the electrons are found outside the nucleus rotating in a definite path

Answer 29

Complete Atomic Structure

Question 30

symbol is shown and the electrons are distributed represented by half shell

Answer 30

Half-shell notation

Question 31

the nucleus is represented by the symbol of the element and only the electrons on the last shell are distributed along the atom using dots, dashes, etc.

Answer 31

Electron Dot Notation/Lewis Structure