Ap Chem Basic Terms Pt 1 Flashcards
Aqueous solutions
Something dissolved in water
Solution
A mixture of 2 things
Solvent
“Dissolving medium” ex: water
Solute
Substance that is being dissolved ex: salt
2 parts of a solution
Solvent
Solute
Electrolyte
A solution that contains ions and can conduct electricity
Non electrolyte
A solution that does not contain ions and does not conduct
All ionic substances are
Electrolytes
- Covalent compounds do not
- Molecular = covalent =
- Acids are
- Ionize
- Nonmetals
- Electrolytes
Strong electrolytes
100% ionization
All ionics
7 strong acids
Weak electrolytes
Partial ionization (small %)
Any other acid
Strong and weak electrolytes depend on
% ionization
7 strong acids
HCl
HBr
HI
HNO3
H2SO4
HClO4
HClO3
Accuracy
How close a measured value is to the correct or “actual” value
*to discuss accuracy we must know actual value
Precision
How close multiple measurements are to each other
*has nothing to do with the correct value
Error
Most measurement contain some amount of error
Error = experimental value (we measured) - actual value
Percent error
% error |experimental - actual / actual| x 100
- always positive
Density
A ratio of an objects mass to its volume
Density = mass/volume
D = M/V
Density
A ratio of an objects mass to its volume
Density = mass/volume
D = M/V
Changes in temp = changes in density
Water displacement method
- Measure water
- Put object in
- Measure change
Absorption
When energy is added to an e- and that e- moves to a higher energy level
Emission
Energy is released and an e- falls from a higher to a lower energy level
Scientific Notation
Shorten numbers and eliminates zeros
Based on powers of 10
Scientific Notation
Shorten numbers and eliminates zeros
Based on powers of 10
Valence Electrons
e- in highest energy level
Core e-
Inner e-
Core + valence =
Total electrons
Valence shortcut
Group 1 = 1 valence
Group 2 = 2 valence
Etc.
Valence shortcut
Group 1 = 1 valence
Group 2 = 2 valence
Etc.
Octet Rule
Atoms are stable (unreactive) when they have 8 valence electrons
Why? Full energy level
Goal: all atoms want 8 valence electrons to become stable like noble gases
Diatomic molecules
7 elements do not exist as single atoms in nature. Instead they exist as diatomic molecules
States of Matter
Solid (s)
Liquid (l)
Gas (g)
Aqueous (aq): dissolved in water
Chemical bonding
Why? All want 8 valence e- to fill their outer energy level
Two ways:
1. Loss and gain of e- (ionic bonding)
2. Sharing e- (covalent)
Ionic
Occurs between:
metal and a nonmetal
+ or -
Cations and anions
Covalent
Occurs between 2 non metals
Atomic orbitals
Where e- live within the energy level
S Orbital = max # of electrons: 2
P orbital = max # of electrons: 6
D orbital = max # of electrons: 10
F orbital = max # of electrons: 14
Periods =
Energy level
International System of Units (SI) / Metric System
Based on Powers of 10
Base units:
Length: meter (m)
Mass: gram (g)
Temperature: Celsius (C) and Kelvin (K) no negative Kelvin
Time: seconds (s)
Amount/quantity: mole (mol)
1 mol =
6.022 x 10^23
Absolute zero =
Molecular motion ceases
