4.1.2 - Atomic Structure Flashcards
(28 cards)
What was Dalton’s atomic theory?
Atoms were tiny spherical particles
What was Thomson’s atomic theory?
Negatively charged electrons
Plum Pudding Model
What was Rutherford’s experiment?
Firing positive alpha particles at thin gold foil.
What were the results to Rutherford’s experiment?
The atom had a positively charged nucleus with the atom being mostly empty space.
What atom model did Rutherford propose after his experiment?
Nuclear model
What did Chadwick discover?
Neutrons
Why was Chadwick’s discovery so important?
It explained why the mass of atoms was greater.
What are electron shells?
Rings orbiting the nucleus
What are electron shells also known as?
Energy Levels
How big is an atom in m? Give your answer in standard form.
1 x 10^-10m
How big is an atom’s nucleus in m? Give your answer in standard form.
1 x 10^-14m
What is the mass and charge of a proton?
mass = 1
charge = +1
What is the mass and charge of an electron?
mass = almost zero (1/200)
charge = -1
What is the mass and charge of a neutron?
mass = 1
charge = 0
Where are the protons found?
In the nucleus
Where are the electrons found?
On the shells/energy levels
Where are the neutrons found?
In the nucleus
Why do atoms have an overall neutral charge?
There are the same number of protons and electrons.
What is the atomic number of an atom?
Number of protons/electrons
How do you calculate the number of neutrons?
Subtract the atomic number from the mass number
What is the Mass Number also known as?
Proton Number
What is the Mass Number?
The total number of protons and neutrons in its nucleus
What is the atomic number also known as?
Proton Number
What is an isotope?
Multiple forms of the same element with the same amount of protons and electrons, but a different number of neutrons.
