Chemistry

Billiard Ball Model

John Dalton; ATOM is hard & indestructible

Plum Pudding Model

JJ Thomson; + Charged Sphere

Nuclear Model

Ernest Rutherford; Mass & + Charges of an Atom is on the Nucleus

Planetary Model

Niels Bohr; Electrons travel in ORBITS; Energy proportional to Nucleus

Quantum Model

Electron is a WAVE; ORBITALS

Alkali Metals

• highly reactive metals

• one excess electron (+1 charge)

• forms with HALOGENS

halogens

• highly reactive NON-metals

• lack one electron (-1 charge)

• forms with ALKALI METALS

noble gases

• inert gases

• unreactive, very stable

• full outer shell of 8 electrons

metalloids

• has both properties (metal and nonmetal)

isotopes

atoms of the same element
differs in NEUTRONS

Ionization Energy

Energy required to remove an electron from an Atom

Electron Affinity

Gain Electrons

Electronegativity

Attract Electrons

Aufbau Principle

every element has the same electron configuration

just + 1 in the next one

Hund’s Rule

Fill up orbitals one by one before pairing

Solution

Particles Dissolve
Particles Settle
Size of Particles - small

Colloid

Particles Dissolve
Particles Settle
Size of Particles - medium

Suspension

Particles Dissolve
Particles Settle
Size of Particles - Large

Measuring Volumes - Liquid

Use a Graduated Cylinder

Measuring Volumes - Irregular Solids

Volume = Rise in Water Level

Measuring Volumes - Gases

Pressure is measured

Kinetic Molecular Theory of Gases

Particles are INFINITELY SMALL
Particles are in a CONSTANT RANDOM MOTION
PERFECTLY ELASTIC COLLISIONS
DIRECTLY PROPORTIONAL to temperatures

Law of Definite Proportion/Composition

DEF / DIFF Variants

H₂ O (Sea)
H₂ O (Bottle)

Law of Multiple Proportions

Multiple FORMATS

CO
CO₂

Law of Conservation of Energy

Neither Energy can be created nor destroyed

Can only change forms

Entropy (s)

degree of disorder

Enthalpy

heat transferred between system and surroundings at constant pressure

Specific Heat

q=mcΔt

q = heat lost or gained
c = specific heat

Energy needed to raise by ONE DEGREE

Boyle's Law

$$P1V1=P2V2$$

Charles's Law

$\frac{V1}{T1}=\frac{V2}{T2}$ , where $V$ is volume and $T$ is temperature in Kelvin.

Gay-Lussac's Law

$\frac{P1}{T1}=\frac{P2}{T2}$ , where $P$ is pressure and $T$ is temperature in Kelvin.

Combined Gas Law

$$\frac{P1V1}{T1}=\frac{P2V2}{T2}$$

Avogadro's Law

$V \propto n$ at constant temperature and pressure
$\frac{V1}{n1}=\frac{V2}{n2}$ , where $n$ is the number of moles

Ideal Gas Law

$PV = nRT$, where $R$ is the ideal gas constant (0.0821) and $n$ is the number of moles.

Dalton's Law of Partial Pressures Formula

Dalton's Law states that the total pressure of a mixture is the sum of the partial pressures: $P_{total} = P\_1 + P\_2 + P\_3 + ...$.