Atoms Flashcards
What is an element
An element is a substance made up of one type of atom and cannot be broken down
What is a compound
A compound is a substance made up of more than one type of elements and is chemically bonded
What is a mixture
A mixture is a substance made up of more than one type of elements but is not chemically bonded
Atoms cannot be…. or ….. during a chemical reaction, only …….
created or destroyed, only rearranged
What subatomic particles are in the nucleus and what charge do they have
Protons - positive +1
Neutrons - neutral 0
What subatomic particle is found outside the nucleus and what charge
Electrons - negative -1
What is an atomic number (at the bottom)
the amount of protons in the element
What is the mass number (at the top)
the amount of protons and neutrons in that element
How do you calculate the amount of neutrons
mass number - atomic number
What is the overall charge of an atom
0, its neutral
Pros and Cons of the solar system model
Pros
- Correctly shows locations of subatomic particles
- Correctly shows charges
Cons
- Atoms are 3D, not 2D
- Nucleus is much smaller than what the diagrams show
What did JJ Thomson discover and what was his model
He discovered the electron and his Plum Pudding model suggested that atoms were a sphere of positive charge that had negatively charged electrons evenly spread throughout
What did Ernest Rutherford discover and how
He discovered the nucleus when he fired positive alpha particles at a gold foil expecting it to deflect back but it passed through empty space
Some did deflect due to a dense positive nucleus
What did Niels Bohr and James Chadwick discover
Bohr adapted the nuclear model, showing that electrons orbit the nucleus at specific distances aka discovered the electron shells
Chadwick discovered the neutron, in the nucleus that adds mass to the atom
16
O
oxygen
8
List
The amount of protons, neutrons and electrons
8 protons, 8 neutrons, 8 electrons
