Exam 1 Study Guide Flashcards
(28 cards)
homogeneous mixture
mixture is uniform throughout; ex. salt water
heterogeneous mixture
mixture is not uniform throughout; ex. ice cubes in a drink, sand and water.
Daltonβs atomic theory
All matter consists of tiny particles called atoms.
An atom cannot be created, divided, destroyed, or converted to any other type of atom.
Atoms of a particular element have identical properties.
Atoms of different elements have different properties.
Atoms of different elements combine in simple whole-number ratios to produce compounds (stable combinations of atoms).
Chemical change involves joining, separating, or rearranging atoms.
Convert to C from F
Β°πͺ = Β°π - ππ (π/π)
Convert to F from C
Β°π = Β°π (π/π) + ππ
Convert to K from C
K = Β°C + 273.15
Convert to C from K
Β°C = K - 273.15
Convert to C from K
Β°C = K - 273.15
Aufbauβs Principle
e- are placed in order of low to high NRG levels (build up principle)
Pauli Exclusion Principle
No two e- in an atom can have the atomic orbital (1 spin up and 1 spin down)
Hundβs Principle
When filling orbitals that have the same energy, place one e- in each orbital before completing pairs.
When are double bonds necessary in a Lewis structure?
If there arenβt enough e- for a full octet after first connecting them with single bonds.
Calculation for average atomic mass from two isotopes
avg. atomic mass of element = [(%abundance/100) x (mass in amu)] + [(%abundance/100) x (mass in amu)]
add calculations of the two isotopes
n (principle quantum number)
size (distance of the e- from the nucleus
l (angular)
shape of the orbital
m sub l (magnetic)
orientation of the orbital
m sub s (spin)
spin up and spin down
e- orbitals
1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p6, 5s2, 4d10, 5p6
VSEPR Theory
repulsions between e- groups determine the geometry of a molecule.
lone pair and bonding e- around an atom seek to be as far away from each other as possible.
molecular geometry is determined by the number of e- groups and the max bond angle that can be acheived between the groups.
e- geometry for 2 e- groups
linear ( ex. CO2)
e- geometry for 3 e- groups
trigonal planar
if lone pairs exists around an atom, the molecular geometry differs from the electron geometry as bent.
e- geometry for 4 e- groups
tetrahedral e- geometry
molecular geometry:
one lone pair is trigonal planar
two lone pairs is bent
intensive property
property of matter that is independent of the quantity of the substance. Boiling and melting points are intensive properties. For example, the boiling point of one single drop of water is exactly the same as the boiling point of a liter (L) of water.
extensive property
depends on the quantity of a substance. Mass and volume are extensive properties. There is an obvious difference between 1 gram (g) of silver and 1 kilogram (kg) of silver; the quantities and, incidentally, the monetary values, differ substantially.
