Atomic Structure

Question 1

What subatomic particles are found in every atom?

Answer 1

• Protons
• Neutron
• Electrons

Question 2

How big is an atom and how big is its nucleus?

Answer 2

0.1 nm

the nucleus is 1/10,000 of the atom

Question 3

Where are the subatomic particles found in the atom?

Answer 3

• Protons and Neutrons found in the nucleus

- Electrons orbit the nucleus on energy levels/ shells

Question 4

What are the relative masses of the subatomic particles?

Answer 4

Proton   = 1
Neutron = 1
Electron = negligible/ very small

Question 5

What are the relative charges of the subatomic particles?

Answer 5

Proton   = +1
Neutron = neutral/ 0
Electron = -1

Question 6

What is the charge of the nucleus?

Answer 6

Positive

Question 7

What is the charge of the overall atom? why?

Answer 7

Neutral:

-The positive charge of the nucleus and the negative charges of the electrons balance out

Question 8

What is the relationship between the No. of Electrons and the No. of Protons?

Answer 8

They are equal

Question 9

What are ions?

Answer 9

Electrically charged particles formed from neutral atoms gaining or losing electrons

Question 10

What happens when an atom loses electrons?

Answer 10

• There will be more protons than electrons in the atom
• Charges are no longer balanced
• Positively charged ions form

Question 11

What happens when an atom gains electrons?

Answer 11

• There will be more electrons than protons in the atom
• Charges are no longer balanced
• Negatively charged ions form

Question 12

What is the mass number of an atom? Where is it written on atoms shown on the periodic table?

Answer 12

The total number of protons and neutrons in an atom

it is the bigger number usually on the TOP

Question 13

What is the atomic number of an atom? Where is it written on atoms shown on the periodic table?

Answer 13

The number of Protons ONLY in an atom

it is the smaller number usually on the BOTTOM

Question 14

What happens to an atom during chemical reactions?

Answer 14

-Involves the gain/ lose of electrons

do not involve the nucleus, so the number of protons does not change

Question 15

What is meant by the term electron configuration?

Answer 15

A description of how the electrons are arranged around the nucleus in an atom

Question 16

How are electrons removed from an atom?

Answer 16

-Removal of electrons happen one-by-one, starting from the outermost electrons

Question 17

What are isotopes?

Answer 17

Atoms of an element with the same number of protons, but different number of neutrons/
They have a different mass number

Question 18

What is a mass spectrum used for?

Answer 18

To find the number and abundances of isotopes of an element

Question 19

What is shown on a mass spectrum?

Answer 19

• the m/z ration of ions is displayed on the x-axis (assuming the charge of every ion is +1 the m/z ratio is equal to the mass of the ion)
• the y-axis gives information on the number of ions/ abundance of any particular m/z value detected
• each peak indicates a new species

Question 20

What is the relative atomic mass of an element?

Answer 20

The weighed mean of the mass numbers of the isotopes of an element

Question 21

What are the 2 formulae for R.A.M?

Answer 21

R.A.M = [SUM OF (Isotopic mass x abundance)] / 100
OR
R.A.M = [SUM OF (Isotopic mass x relative abundance] / [Total Abundance]