Atomic Structure

Question 1

J.J Thompson

Answer 1

Discovered electron can be pulled from atom using high voltage
(A current bun that has currents removed was his model)

Question 1

Ernest Rutherford

Answer 1

Proved atom was not solid but had very dense centre called nucleus

Question 2

Niels Bohr

Answer 2

Idea of nucleus central with electrons orbiting

Question 3

John Dalton

Answer 3

Published atomic theory:
Elements made from atoms, cannot be broken up (untrue)
Atoms of same element are identical
Atoms combine to make compounds

Question 4

What charge does an atom contain overall

Answer 4

No charge

It has same amount of protons and electrons so they cancel out each other’s charges

Question 5

What is the approximate mass and radius of an atom

Answer 5

Mass 10-23g

Radius 10-10m

Question 6

Which atomic particles have equal relative mass

And which has significantly less mass

Answer 6

Proton and neutron

Electron

Question 7

Element

Answer 7

Substance that cannot be broken down chemically and contains only one type of atom

Question 8

Compound

Answer 8

Contains at least two elements that are chemically combined

Question 9

What does the atomic number tell

Where is it in periodic table

Answer 9

It is the lower number eg. lithium-3 magnesium-12

Tells number of PROTONS in atom and also number of ELECTRONS

Question 10

What does the relative atomic mass tell

Where is it in the periodic table

Answer 10

It is the higher number eg. lithium-7 magnesium-24

This is ELECTRONS and PROTONS added together

Question 11

How can realative atomic mass (higher number) be used to calculate the number or neutrons in the element

Answer 11

relative atomic mass - atomic number = number of neutrons

Eg. Oxygen (16-8= 8 neutrons) Sodium (23-11= 12 neutrons)

Question 12

We can arrange the electrons by using the atomic mass (lower number) by filling shells

How many electrons can first shell hold
How many electrons can second shell hold
How many electrons can third shell hold

Answer 12

first shell can hold 2 electrons
Second shell can hold 8 electrons
Third shell can hold 8 electrons

Question 12

How is the period of an element determined

Answer 12

The horizontal row

The period number an element is in, corresponds with the amount of shells of electrons it has

Question 13

How is the group of an element determined

Answer 13

The vertical column

The group number corresponds with amount of outer shell electrons

Question 14

What are isotopes

Answer 14

Varieties of different numbers of neutrons in an element

Question 15

Why is an atom’s nucleus positively charged

Answer 15

The nucleus is made up of protons (positively charged)
and neutrons (neutrally charged) 

The space around the nucleus is occupied by negativity charged electrons arranged in shells