COLLIGATIVE PROPERTIES OF SOLUTION

Electrolytes

a substance that dissolves in a liquid solvent and provides ions that conduct electricity

Non-Electrolytes

is a liquid or solid substance that does not allow the flow of an electric current, either in solution or in its pure state, such as water or sucrose.

Examples of Electrolytes

• Gatorade

• Pocari Sweat

• Vita Coco (Pure Coconut Water)

Examples of Non-Electrolytes

• Methanol

• Acetone

• Benzene

Colligative Properties of Solutions

Any physical effect of the solute on the solvent is a colligative property

1. Boiling Point Elevation

2. Freezing Point Depression

solute particles

Colligative properties depend on the concentration of ________ _________.

Boiling-Point Elevation

The _________ of any solution that contains a non-volatile solute is always higher than the ________ of the pure solvent

change in boiling point

ΔTb

Kb

boiling point elevation constant

m

molality of the solute

Positive

In boiling-point elevation ΔTb is always ______.

Positive or Negative?

Freezing-Point Depression

The temperature of a solution must be lowered below the __________ of the pure solvent to freeze it,

Negative

In freezing-point depression ΔTf is always ______.

Positive or Negative?

Tb(solution) = Kb * m

Boiling-Point Elevation Formula

Tf(solution) = Kf * m

Freezing-Point Depression Formula

PHYSICAL CHANGE

When a substance undergoes a ______ _____, its composition remains the same despite its molecules being rearranged.

CHEMICAL CHANGE

When a substance undergoes a ________, its molecular composition is changed entirely. Thus, chemical changes involve the formation of new substances.

THERMOCHEMISTRY

is the study of heat change in chemical reactions

Law of Conservation of Energy

"Energy cannot be created or destroyed but can be changed from one form to another."

Open System

Exchanges both matter and energy with the surroundings

(e.g., an uncovered hot coffee cup where steam escapes)

Closed System

Exchanges only energy, not matter

(e.g., a cup with a lid that prevents steam from escaping but allows heat transfer)

Isolated System

No exchange of matter or energy

(e.g., a well-insulated thermos).

Endothermic Reaction

Absorbs heat from the surroundings.

Example: Ice melting

Exothermic Reaction

Releases heat into the surroundings.

Example: Burning wood.

cold

Endothermic reactions feel ____ because they absorb heat

hot

Exothermic reactions feel ___ because they release heat

First Law of Thermodynamics

states that energy cannot be created or destroyed; it can only be transferred or transformed.

Law of Conservation of Energy

First Law of Thermodynamics is also called the ______________ in thermodynamic systems.

same

In an isolated system, the total energy stays the _____.

Rudolf Clausius and William Thomson

Around 1850 ______________ and ____________ states that “Heat DOES NOT SPONTANEOUSLY flow from a colder body to a hotter body” this become the basis of Second Law of Thermodynamics.

1850

Around ____ Rudolf Clausius and William Thomson (Lord Kervin) states that “Heat DOES NOT SPONTANEOUSLY flow from a colder body to a hotter body” this become the basis of Second Law of Thermodynamics.

Second Law of Thermodynamics

states that heat flows from hot to cold, and entropy (disorder) in an isolated system always increases, making processes irreversible

First Law

Energy is conserved

The total quantity of energy in the universe stays the same.

Second Law

Entropy increases, and heat flows naturally from hot to cold.

Quality of energy, states that as energy is transferred or transformed. More and more of it is wasted.

ENTROPY

Degree of randomness disorder

Solids

_____ have low entropy

liquid

_____ have more entropy

gasses

_____ larger amount of entropy

Josiah Willard Gibbs

a professor at Yale University who proposed another thermodynamic quantity represented by the symbol G

Free Energy

Another name for Gibbs

G < 0

The reaction is spontaneous in the forward direction

G > 0

The reaction is nonspontaneous

G = 0

The system is at equilibrium. There is no net change

Ionic Bonds

______ form when electrons are transferred from one atom to another

spontaneous or nonspontaneous

Gibbs free energy helps determine whether a reaction is _______________

Crystal

Which of the following is NOT a fundamental state of matter?

• Solid

• Liquid

• Plasma

• Crystal

Neutral

What is the charge of a neutron?

spontaneous

If gibbs free energy (ΔG\Delta GΔG) is negative, the reaction is __________

nonspontaneous

If gibbs free energy (ΔG\Delta GΔG) is positive, the reaction is __________

hot to cold

Heat naturally flows from ________