IH Chemistry Flashcards
Matter
Any that occupies space and has mass
Substance
Matter that has the same properties and composition e.g. atoms and molecules
Elements
A substance that cannot be decomposed to other substances
Compounds
Substance that consists of at least 2 elements and can decompose to other substances
Mixtures
Like compounds but components are interdependent and can be removed from the mixture
Atomic structure
Dense nucleus of protons and neutrons with outer volume containing electrons
Groups
Columns in periodic table, consists of elements with similar properties
Electron configuration
Electron filling scheme for a given element
Chemical properties
Bonding characteristics of an element though valence electrons. Similar properties should have similar valence shell configurations.
Covalent bonding
Atoms share electrons
Ionic bonding
Transfer of electrons
Octet rule
The tendency for an atom to have 8 valence electrons
Polar covalent bond
Uneven electron density in a covalently bonded molecule
Electronegativity
The tendency for an atom to have higher electron density
What molecules tend to be nonpolar?
Ax and CxAy
What is the Law of Conservation of Energy?
Energy cannot be created or destroyed, only change in form
Heat of reaction
The energy released or absorbed in a reaction
Solid
Definite shape and volume, strong intermolecular forces
Crystalline solid
Solid with crystal structure
Amorphous solid
Solid without a crystalline structure
Liquids
Molecules held a relatively small distances within a definite volume at a fixed temperature
Gases
Weak intermolecular forces, fills the shape of the container. Volumes affected by temperature and pressure.
Aliphatic hydrocarbon
Saturated, single bonds, non-polar
Unsaturated hydrocarbon
Double or triple bonds (alkenes, alkynes)
Aromatic hydrocarbons
Ring structure, follows Huckel’s rules
Methyl
1 carbon
Ethyl
2 carbons
Propyl
3 carbons
Butyl
4 carbons
Isopropyl
3 carbons in a trident shape
Polyaromatic hydrocarbons
Multiple aromatic rings in 1 molecule
Alcohol
R-OH
Ether
R’-O-R”
Aldehyde
RCOH
Ketone
RCOR’
Carbonxylic Acid
RCOOH
Amine
R-NH2
Nitrile
CN
Beer’s Law
Absorbance = molar absorptivity * path length * concentration
A = abc
Qualitative analysis
Is it there or not?
Quantitative analysis
How much is there?
Boyle’s Law
P1V1 = P2V2
Charles Law
V1/T1 = V2/T2
Gay-Lussac’s Law
P1/T1 = P2/V2
All the laws combined
V ∝ T/P
Ideal gas law
PV = nRT
Kinetic theory of gases
- A gas consists of a large number of very small particles
- Net volume of particles is negligible
- Elastic collisions in straight lines
Spectroscopy
Measures interactions of chemical w/ EMR
Electrochemical
Measures interaction of chemical with electric field
IR spectroscopy
Molecular vibrations and rotations from IR exposure
Xray diffraction
Incident xray gives off characteristic patter
Xray fluorescence
Characterstic secondary xray from incident xray
Atomic absorption and emission spec
Observe emitted radiation from decay of excited compound
Gas chromatography
Measures retention times of components in mobile phase in addition to quantitative analysis
HPLC
similar to GC but mobile phase is liquid and is used for less volatile or more reactive chemicals
Ion chromatography
Similar to HPLC but uses ion exchange resins for separation
Ion exchange electrodes
Glass electrode that gives highly selective response to hydrogen ions, commonly used in pH meters
Electron capture detectors
Isotope releases electrons in carrier gas towards an anode to create a current. Electron capturing analytes take an amount of those electrons, affecting the current.
Flame ionization detector
Creation of organic ions by passing H2 through a flame, measuring conductivity of the flame. Used with many organic compounds.
Photoionization detector
Creates ions through UV exposure, measures conductivity of gases in the light field. Used with organics, especially aromatics.
Fick’s Law of Diffusion
W = D (A/L) (C1 - C0)
W = mass transfer rate D = Diffusion coefficient A = Frontal area of static layer L = Length of static layer C1 = ambient concentration C0 = concentration at collection surface (should be 0)
