Topic 1 - Structure of Atoms

what was the dalton model

what was the plum pudding model

what was the nuclear model

what was the planetary model

what was erwins model

what is the structure of an atom

a nucleus containing protons and neutons surrounded by electrons in shells

what is the relative charge and relative mass of a proton

RC: 1+ RM: 1

what is the relative charge and relative mass of a neutron

RC: 0 RM: 1

what is the relative charge and relative mass of a electron

RC: -1 RM: almost 0

why do atoms contain equal numbers of protons and electrons

so that the atom has no charge and is neutral as the charge of protons and electrons cancel each other out

how big is the nucleus

the nucleus is very small comapred to the overall size of the atom

Where is most of the mass concentrated in an atom

the nucleus

what is the meaning of ‘mass number' of an atom

The mass number of an element tells us the number of protons and neutrons

in an atom

how would you describe atoms of a given element

having the same number of protons in the nucleus and that the number is unique to that element

What are isotopes

isotopes are different atoms of the same element containing the same number of protons but different number of neutrons in the nuclei.

how do you calculate the number of protons,neutrons and electrons in an atom

number of protons = atomic number

number of electrons = atomic number

number of neutrons = mass number - atomic number

Explain how the existence of isotopes results in relative atomic masses of some elements not being whole numbers

The relative atomic masses of elements are often not whole numbers because they represent the weighted average of the masses of all the isotopes of that element, taking into account their natural abundance

how to calculate relative atomic mass - example given in answer