chem solutions

Solutions are a ___ mixture

Homogenous

What is a solute

the substance being dissolved

What is a solvent

the substance doing the dissolving

What is dissolution

the process of making a solution

what is dissolution process

• solute dissociates into ions

• solvent molecules surround ions

• repeats until equilbrium is reaches

What are the 3 factors of dissolution

-Surface area

-Temperature

-Aggitation (shaking/stirring)

-When these increase, dissolution INCREASES

Pressure affects ___ solubility

gas

When pressure increases, gas solubility ___

increases

what is effervescence

escape of gas from solution

What is henry’s law equation (with pressure and solubility)

S₁ / P₁ = S₂ / P₂

Solids are ___ soluble at higher temperatures

more

Gases are ___ soluble at high temperatures

less

On a solubility curve, what shows saturated solutions?

points on the lines

On the solubility curve, what shows supersaturated solutions?

Points above the line

One the solubility curve, what shows unsaturated solutions?

Points below the line

Elements/compounds with a higher precentage are usually the "solvent/solute?

solvent

Equation for Molarity (M)

M= mol solute/ L solution

M= n/v

For questions with dilution/concentration use this equation

M₁V₁= M₂V₂

M= molarity

V= volume

Molality (m) equation

m= mol / kg

m= mol solute / kg solvent

Mass percentage equation

Mass % of solute = mass of solute/ total mass of solution x 100

Volume percentage equation

Volume % of solute = solute volume/ solution volume x 100

How to andwer questions that ask to rank solutions

-Count the number of particles each solution produced when dissolved. Put in order

-Non-metal solutions count as 1 particle

When temperature increases what happens to particles

they move faster, which increases collisions. this increases solubility.

For dilution questions, how do you dilute a solution back to a certain molarity

-Use M1V1=M2V2 equation

-Solve for V2

**Measure the stock solution, and add water until volume reaches v2

What do collegiative properties depend on

the amount of dissolved solute

What do collegiative properties NOT depend on

the identity of the solute

Why do substances need to be nonvolatile to exhibit colligative properties

So that they will stay in the solution and not evaporate. Volatile substances will evaporate, which changes their concentration

What is vapor pressure

Pressure of gas above its liquid state

What do dissolved solutes (colligative properties) do to vapor pressure

Trap vapor in liquid and decrease vapor pressure

What do dissolved solutes (colligative properties) do to the boiling point

-particles take up space at surface when boiling, and block water molecules from escaping as gas

Boiling point increases

What do dissolved solutes (colligative properties) do to the freezing point

-Particles stop the solvent from forming an orderly pattern

-Stops the liquid from freezing

Depresses the freezing point

What is osmotic pressure

External pressure applied to stop osmosis (solvent transfering across a semipermeable membrane)

What do dissolved solutes (colligative properties) do to osmotic pressure

-Solute particles increase, making osmotic pressure increase

Solubility curves for gases have ___ slopes

negative