Unit 0 test review Flashcards
(23 cards)
Ionization energy
Amount of energy required to move an electron.
increases going up and to the right
Electronegativity
Ability of an atom to attract electrons within a covalent bond. (increases going up and to the right)
Electron affinity
The ability of an atom to attract electrons. How much an atom is willing to ‘pay’ for a electron. increases going up and to the right)
Atomic Radius
The size of the atom or how large the atom is. (increases going left and down)
Shielding effect
Describes the decrease in attraction between an electron and the nucleus in any atom with more than 1 electron shell. The higher the shield effect, the larger the atom because the energy levels block the pull of the nucleus.
What atoms are made up of
- nucleus is made up of protons(+) and neutrons(n)
- surrounded by e(-)
Electron configuration for Fluorine
2e-, 7e-
How to calculate atomic mass
number of neutrons + number of protons
What is an isotope
Different amounts of neutrons in the nucleus.(same type of atoms)
Democritus
Discovered that the atom is the smallest individual particle.
Dalton
Invented the first practical model of the atom.(Matter is made up of tiny particles called atoms)
Thomson
Discovered electrons using the plum pudding model. (used cathode ray tubes)
Rutherford
Discovered the nucleus using the gold foil experiment
Chadwick
Discovered neutrons
Bohr
electrons travel in orbits around the nucleus
Ionic
- occurs when electronegativity is greater than 1.7
- very strong attraction, therefore high boiling/melting points
- ionic compounds tend to be solids at room temperature
Intramolecular Forces
Forces which keep the molecule together.(ionic, polar, non polar) __________
Intermolecular forces
attractive forces between molecules, responsible for the state of the molecule. (ionic, hydrogen bonding, dipole-dipole, London Forces) ——–
Dipole-Dipole attractions
- occur when the molecule is polar
- partial positive charges from one molecule are attracted to partial negative charges of another molecule
- intermediate strength attraction therefore intermediate boiling/melting points
- Compounds tend to be liquids at room temperature
Hydrogen Bonding
- a special type of dipole-dipole attraction that occurs when H is bonded to either N,O or F
- This bond is stronger than a regular dipole-dipole bond due to increased electronegativity
- higher boiling/melting points(still lower than ionic)
- compounds tend to be liquids at room temperature
London Forces
- attraction between an instantaneous dipole and an induced dipole
- very weak force
- low boiling/melting points
- compounds tend to be gasses at room temperature
polar
EN between 0.5 and 1.7 medium strength
Non-polar
EN lower than 0.5 weakest strength
