Chem Unit 4

Boyle’s Law

• Pressure of a gas is inversely related to its volume when T is constant

• Product P x V is constant when temp and gas is held constant

• If volume decreases, pressure increases

Charles’s Law

• The kelvin temp, of a gas is directly related to its volume

• Pressure and moles of gas are constant

• When the temp is a sample of gas increased, volume increase at constant pressure

Gay-Lussac’s Law

• Pressure exerted by a gas is directly related to the kelvin temp of a gas

• Volume and amount of gas are constant

Combined Gas Law equation

P1V1T1 = P2V2T2

What does Avogadro’s Law state?

Volume is directly proportional to moles of gas

What are STP conditions?

0°C (273 K) and 1 atm (760 mmHg)

Ideal Gas Law equation

PV=nRT

Values of R for ideal gas law equation

0.0821 L·atm/(mol·K) or 62.4 L·mmHg/(mol·K)

Definition of a solute

The component present in a smaller amount that is dissolved in the solvent

Why ionic compounds dissolve in water

Water molecules attract and separate ions through hydration

Strong electrolyte definition

Dissociates 100% into ions in water.

Weak electrolyte

does not dissociates 100% into ions in water.

Nonelectrolyte

Dissolves as molecules and produces no ions.

What is an equivalent (Eq)?

The amount of an ion that supplies 1 mole of electrical charge.

Solubility definition

Maximum amount of solute that dissolves in a given amount of solvent at a specific temperature.

Unsaturated solution

Contains less than the maximum solute; can dissolve more.

Saturated solution

Contains the maximum solute; undissolved solute remains.

Effect of temperature on solubility of solids

Solubility of most solids increases as temperature increases.

Effect of temperature on solubility of gases

Gas solubility decreases as temperature increases.

Henry’s Law

Gas solubility is directly related to the pressure of the gas above the liquid.

Colloid

Medium particles that do not settle and cannot be filtered.

Suspension

Large particles that settle and can be filtered.

What are colligative properties?

Properties affected by the number of solute particles: vapor pressure lowering, boiling point elevation, freezing point lowering, osmotic pressure.

Osmosis

Water flows from lower solute concentration to higher solute concentration.

Osmotic pressure

Pressure needed to stop osmosis.

Catalysts

speeds up the rate of
the reaction by providing an alternative
pathway that has a lower activation
energy

Equilibrium

when no further changes take place in
the concentration of the reactants and products.

Law of Mass Action – Equilibrium Constant

States that for a reversible reaction at ___ the ratio of the concentration of the products to the concentration is always equal to a constant

Le Châtelier’s Principle

states that when a stressor is placed on a reaction at equilibrium, the system responds by changing the rate of
the forward or reverse reaction in the direction that relieves that stress.