General Chemistry Lecture Notes

Flashcards for General Chemistry Lecture Review

General Chemistry

A branch of science that studies matter in terms of its composition, structure, properties, changes, and energy.

Matter

Anything that occupies space and has mass.

Mass

The amount of matter present in an object.

Volume

The amount of space occupied by an object.

Weight

Mass multiplied by gravity.

Intensive/Intrinsic Property

Properties that are independent of the amount of matter present.

Extensive/Extrinsic Property

Properties that are dependent on the amount of matter present.

Physical Change

Observed or measured without changing the identity of matter; includes change in phase.

Chemical Change

Describes the change or reaction a substance undergoes, including change in both intrinsic and extrinsic properties.

Solid

Definite shape and definite volume, strongest Intermolecular Forces of Attractaion and Vibration Motion, cannot Compress

Liquid

Indefinite shape and definite volume, strong IFA and Gliding Motion, Weak or None compression

Gas

Indefinite shape and indefinite volume, Weakest IFA and Random Motion, Strongest Compression

Plasma

The fourth state of matter, also known as mesophase or liquid crystals, exhibiting both solid and flow-like properties.

Law of Definite Proportion

A pure compound's composition is always the same regardless of its source; also known as Proust’s Law or Law of constant composition.

Law of Multiple Proportion

Atoms of two or more elements may combine in different ratios to produce more than one compound; also known as Dalton’s Law.

Law of Conservation of Mass

No change is observed in the total mass of the substances involved in a chemical reaction.

Elements

Simplest form of matter that has definite chemical compositions and cannot be decomposed by simple means.

Compounds

Composed of two or more elements that unite chemically in different proportions and cannot be changed into simpler substances under normal conditions.

Mixtures

Substances that are not chemically combined and may be classified according to the nature of particles (homogenous vs. heterogenous) and particle size (solution, colloids, suspensions).

True Solutions

Uniform mixture composed of solute and solvent where atoms, molecules, or ions of the substance become dispersed.

Colloids

Contains particles bigger than those in solutions but smaller than those in suspensions where particles of solute are broken down to the size of molecules but are small enough and dispersed throughout the medium.

Tyndall effect

Light scattering effect by colloids.

Brownian Movement

Zig-zag movement of particles in colloids.

Adsorption

Capacity to adhere (stick) to the surface of colloids.

Suspensions

Coarse mixture wth finely divided solid materials distributed in liquid.

Solubility

Refers to the maximum amount of solute expressed in grams that can be dissolved in 100g of water.

Miscibility

Ability of one substance to mix with another substance.

Henry’s law of gas solubility

At constant temperature, the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid.

Salting-out

Presence of salt decreases solubility.

Salting-in

Presence of salt increases solubility.

Solubility Product Constant (Ksp)

Refers to the limit before saturation Solubility Product Constant.

Unsaturated solution

Q < KSP, Refers to the limit before saturation.

Saturated solution

Q = KSP, Refers to the limit before saturation.

Supersaturated solution

Q > KSP, Refers to the limit before saturation.

Acids

Yields H+/H3O+, Arrhenius Theory.

Bases

Yields OH-, Arrhenius Theory.

Acids

Proton Donor, Bronsted-Lowry Theory.

Bases

Proton Acceptor, Bronsted-Lowry Theory.

Acids

Electron Acceptor, Lewis Theory.

Bases

Electron Donor, Lewis Theory.

Salts

Formed from neutralization reaction.

pH

Measured through Sorensen’s Scale, pH = 7: Neutral, pH>7: Basic, pH<7: Acidic

Buffer

A combination of weak acid and its conjugate base or vice versa that resists changes in pH upon the addition of small quantities of acid or alkali.

Buffer Capacity

The magnitude of the resistance of a buffer to pH changes.

Cathode

Reduction occurs in this electrode.

Atom

Basic unit of matter.

Dalton's model

Model: Billiard Ball, Contributed to: Dalton

Thomson's model

Model: Raisin Bread, Contributed to: Thomson

Rutherford's model

Model: Nuclear, Contributed to: Rutherford

Bohr's model

Model: Planetary, Contributed to: Bohr

Quantum Model

Model: Quantum Mechanical, Contributed to: Schrodinger

Isotope

Same element, same protons, different # of neutrons Isotopes of Hydrogen.

Isotone

Different elements, same # of neutrons.

Isobar

Different elements, same mass #.

Aufbau’s Building Up Principle

Electrons are first placed on the subshell with lower energy level.

Hund’s Rule of Pairing

Electron orbitals are filled up singly.

Heisenberg’s Uncertainty Principle

It is impossible to determine simultaneously the momentum and position of an electron.

Pauli’s Exclusion Principle

No 2 electrons can have the same exact set of quantum numbers.

Principal Quantum Number (n)

Determines the main energy level/electron shell and size of the orbital, Values: Positive integers (1,2,3).

Azimuthal/Angular Quantum Number (l)

Determines the shape and subshell, Values: 0 to (n-1)

Magnetic Quantum Number (ml)

Determines the special orientation, Values: -1 to +1.

Spin Quantum Number (ms)

Describes the spin or rotation. Values: +1/2 = clockwise, -1/2 = counterclockwise.

Metallic property

Property that increases from right to let, top to bottom, Atomic Radius – ½ the distance between 2 nuclei.

Zeroth law

States that if two bodies are each in thermal equilibrium with some third body, then they are also in equilibrium with each other.

First Law

Law of conservation of energy, Energy is neither created nor destroyed but is transformed.

Second Law

Spontaneous Law, Degree of randomness/entropy.

Third Law

The entropy of a pure crystalline solid at zero kelvin is zero.

Gibbs Free Energy

Measure of spontaneity.

Nuclear Change

Change in structure, properties, composition of the nucleus of an atom resulting in the transformation of the element into another element.

splitting of heavy atom

Nuclear Fission

Nuclear Fusion

union of 2 light atoms

Chemical Kinetics

Refers to the study of rate (or speed) of chemical reactions.

Transition State Theory

Reactants will undergo a transition state in order to produce products.

Le Chatelier’s Principle

If a stress is applied or placed on an equilibrium system, the system will respond by altering the equilibrium in such a way as to minimize stress.

Law of Mass Action

States that the rate of the reaction Is proportional to the product of the concentrate of the reactants to the power of its coefficient in a balanced equation.