Chapter 4 Key Concepts Flashcards
Who proposed the theory that all matter is made of individual particles called atoms, which cannot be divided?
Dalton
What did Thomson’s experiments prove about atoms?
That atoms could be broken down into even smaller particles
According to Rutherford’s model all of an atoms charge is concentrated where?
In the Nucleus
What are the 3 types of subatomic particles called?
Protons, electrons, and neutrons
Protons, electrons, and neutrons can be distinguished by what?
Mass, charge, and their location in the atom
Atoms of different elements have a different number of _______?
Protons
What has the same atomic number of an element, but different mass numbers because they have a different number of neutrons?
Isotopes
When can and electron(s) in an atom move from one energy level to another?
When the atom gains or loses energy.
Why do scientists use the electron cloud model?
To describe the possible locations of electrons around the nucleus
What is the electron cloud is a good approximation of?
How electrons behave in their orbitals
An electron configuration is the most stable when?
When the electrons are in orbitals with the lowest possible energies.
The atoms of any given element always have the same number of protons and __________?
Neutrons
The mass number of an atom is the sum of _______ and ________ in the nucleus.
Protons and neutrons
To find the number of neutrons in an atom you subtract __________ and __________.
Mass number and atomic number
What is the name of the only atom with one proton?
Hydrogen
