Chemistry Moles and Concentration Terms

Study Notes

1 mole = 6.023x10^23 particles
1 mole atoms = gram atomic mass (or 1g atom) = 6.023x10^23 atoms
1 mole molecules = gram molecular mass (or 1 g molecule) = 6.023x10^23 molecules
1 mole ionic compound = gram formula mass = 6.023x10^23 formula units

Normality = (Number of milliequivalents) / (Volume in ml)
Molality (m) = (Number of moles of solute) / (Mass of solvent in kg)
Molarity (M) = (Number of moles of solute) / (Volume of solution in L)
Molarity (M) = (m * M2) / (1 + (mM2 / 1000)) where:
- M2 = molecular mass of solute
-  = density
Mole fraction (X) = (Number of moles of component) / (Total number of moles in the solution)
Mass percentage (w/w) = (Mass of solute / Mass of solution) * 100
Volume percentage (v/v) = (Volume of solute / Volume of solution) * 100
Parts per million (ppm) = (Mass of solute / Mass of solution) * 10^6

Boyle's Law: At constant temperature and amount of gas, Pressure is inversely proportional to volume: P1V1 = P2V2 = Constant.
Charles' Law: At constant pressure, volume is directly proportional to temperature: V = kT.
Gay-Lussac's Law: At constant volume, pressure is directly proportional to temperature: P1/T1 = P2/T2.
Avogadro's Law: At constant temperature and pressure, Volume is directly proportional to the number of moles: V = K4n.
Ideal Gas Equation: PV = nRT where R is the gas constant.
Graham's Law of Diffusion/Effusion: Rate of diffusion is inversely proportional to the square root of the density of the gas: (Rate of diffusion) ∝ 1/√d.
Dalton's Law of Partial Pressure: Total pressure of a mixture of non-reacting gases is equal to the sum of the partial pressures of each gas: PT = P1 + P2 +... + Pn.
Kinetic Energy: Average kinetic energy is directly proportional to temperature.
Van der Waals Equation: Accounts for the non-ideal behavior of real gases using correction factors 'a' and 'b' to account for intermolecular forces and finite volume of gas molecules: (P + (an^2 / V^2)) (V - nb) = nRT.

Radius ratio: The ratio of the radius of the cation (r+) to the radius of the anion (r-) determines the coordination number and geometry of a compound.
Types of Voids:
- Tetrahedral Void: r (tetrahedral) = 0.225R
- Octahedral Void: r (octahedral) = 0.414R
Types of Magnetism:
- Paramagnetism: Presence of unpaired electrons causing attraction to magnetic fields.
- Ferromagnetism: Permanent magnetism due to parallel spin alignment of unpaired electrons.
- Antiferromagnetism: Presence of unpaired electrons with opposing spin orientations, resulting in zero net magnetic moment.

Rate of reaction: Change in concentration of a reactant or product over time.
Order of reaction: Determined by summing up the exponents of the concentration terms in the rate law expression.
Rate constant (k): Represents the rate of reaction under specific conditions.
Half-life (t1/2): Time taken for the concentration of a reactant to reduce to half its initial value.
Integrated Rate Laws for Different Orders:*
Zero order: [A]t - [A]0 = -kt
First order: ln[A]t - ln[A]0 = -kt
Second order: 1/[A]t - 1/[A]0 = kt
Third order: 1/[A]t^2 - 1/[A]0^2 = 2kt
Key Takeaways:*
Reaction order impacts the relationship between half-life and initial concentration.
Higher bond order indicates greater stability and shorter bond length.
Ideal gas law provides an approximation for gas behavior, while Van der Waals equation accounts for real gas deviations.
Radius ratio is a critical factor influencing the structure of ionic compounds.
Hydrogen bonding significantly affects the physical properties of substances.
Chemical kinetics focuses on the rate and mechanism of chemical reactions.

The Arrhenius equation relates the rate constant of a chemical reaction to the temperature and activation energy.
The equation is: k = A * exp(-Ea / RT) where:
- k is the rate constant
- A is the frequency factor (constant)
- Ea is the activation energy
- R is the gas constant
- T is the temperature
Activation energy represents the minimum energy required for molecules to react.
The equation can be written in logarithmic form as: log k = (-Ea/2.303RT) + log A
This form is useful for determining the activation energy from experimental data.

Emulsions are colloidal solutions of two immiscible liquids.
Examples of emulsions include oil-in-water (O/W) and water-in-oil (W/O) emulsions.
Emulsifiers are added to stabilize emulsions, typically long-chain hydrocarbons.
Lyophilic colloids have a strong affinity for the solvent, examples include starchy gum and gelatin.
The temperature coefficient (n) is the ratio of the rate constant at a temperature 10°C higher to the rate constant at the initial temperature.