Chapter 1 - Atoms Flashcards
Proton
Charge = +1 Mass = 1
Neutron
Charge = 0 Mass = 1
Electron
Charge = -1 Mass = 1/2000
What is the strong nuclear force?
The positive charged protons in the nucleus repel one another so there has to be a force that holds them together. Extremely short range force.
Strong enough to overcome the electrical repulsion between protons.
Small atoms have about the same number of protons/neutrons.
Large atoms have to have more than one neutron per proton.
Eventually it gets so big that its unstable.
What is electricity?
Flow of free electrons through conductive material.
What is an orbital?
An orbital includes the space where an electron is to be found 90% of the time. Each electron shell is divided into orbitals. Each orbital has room for one PAIR of electrons.
An electron in an orbital is more like a cloud than a particle (a cloud of electrical charge). Contains a maximum of two electrons.
Electrons like to be in pairs because it allows them to be spin-paired.
What is a covalent bond?
Two atoms SHARING a pair of valence electrons.
Each atom donates one electron.
Strongest type of bond between two atoms.
The hybrid orbital belongs to both atoms at the same time and makes a strong bridge between them.
Can be polar or nonpolar.
Nonpolar : atoms are shared equally.
Polar: one atom is more electronegative than the other.
Covalent Bond movement
Covalent bonds allows parts of the molecule to move, bend, and swivel without breaking.
When substances melt, vaporize, or dissolve, molecules move apart from each other but don’t break down.
What is an Ionic Bond?
Forms between two ions. Ions are atoms or molecule with too many electrons or too few.
Instead of sharing, one atom ‘steals’ the other.
Compounds formed are called Ionic compounds or ‘salts’.
Usually dissolved in water.
