solutions part 1

matter

anything that has mass or volume

pure substance

one type of particle, has the same properties

mixture

combination of more than one type of article seperated by physical mean

• has diff properties for diff particles

element

pure substance that is made up of atoms with the same # of protons/electrons

• cannot be chemically broken down

compound

pure substance made from 2+ elements that are chemically combined

• can be chemically broken down

mechanical/heterogenous mixture

• 2+ visible parts of mixture

• particles not uniformly distributed

solution/homogenous mixture

• one visible part of mixture

• particles are uniformly distributed

solute

substance being dissolved

solvent

substance that is doing the dissolving

what four types of solutions are there?

• solid solid

• solid liquid

• gas liquid

• gas gas

why is water the universal solvent?

because it is polar

disassociation

seperation of ions from each other

• ONLY in ionic substances

how does ion disassociation work in water?

1. due to water’s polarity, its slightly positive end is attracted to the anion, and vice versa

2. they are also attracted to other polar molecules

3. therefore the ions break apart

dissolving

process that creates solutions

what type of change is dissolving, and why?

physical, since no new substance forms

does energy still transfer when dissolving a substance?

yes, since bonds still are created and broken

what are two things that occur when dissolving a substance?

1. molecules spread out more

2. energy is lost/gained

what is the first step when dissolving a substance, and what kind of reaction is it?

intermolecular (bonds between molecules) bonds break

• endothermic, energy is absorbed from outside

what is the second step when dissolving a substance, and what kind of reaction is it?

intramolecular (bonds within molecules) bonds break

• endothermic, energy is absorbed from outside

what is the third step when dissolving a substance, and what kind of reaction is it?

new solute-solvent bonds are created due to molecular attraction

• exothermic (energy is released)

hydration

creation of solute-solvent bonds in aqueous solutions

endothermic

more absorbed energy that breaks bonds

exothermic

more released energy that creates bonds

miscibility

abiity for a liquid to dissolve in another liquid

miscible

liquids dissolve in another in all proportions

immiscible

liquids that cannot dissolve in one another in all proportions

what rule does miscibility rely on?

like dissolves like

can some insoluble solutions be slightly soluble in water?

yes

solubility

measure of the max solute that dissolves in solvent

dilute

small amount of solute relative to the solvent

concentrated

large amount of solute relative to the solvent

saturated solution

no more solute can be dissolved in a solvent

how does temperature affect the saturation of a solution

higher temp = more solute dissolved = higher saturation

what are the two characteristics of a saturated solution?

• creates solid precipitate

• doesn’t look like it changes due to a process called dynamic equilibrium

dynamic equilibrium

ions crystallize at the same rate that solids dissolve in

supersaturated solution

more solute is dissolved than what usually does in solvent

how do you create a supersaturated solution?

• heat up your solution, then let it cool slowly

are supersaturated solutions stable?

no

unsaturated solution

more solute will dissolve in a solution

electrolytes

conduct electricity

what substances are considered electrolytes?

acids, bases, ionic substances (anything with ions)

nonelectrolytes

do not conduct electricity

what substances are considered nonelectrolytes?

molecular, insoluble ionic compounds

when lighting a lamp with chemical compounds, what shows an electrolyte?

• when the light glows

• the brighter the light, the stronger the electrolyte

what are the three factors that affect solubilty?

• temperature

• pressure

• miscibility

in a solid-water solution, how does temperature affect solubility? name an example.

higher temperature, higher solubility.

in a gas-water solution, how does temperature affect solubility? name an example.

higher temperature, lower solubility

how do you figure out what type of solution a compound is on a solubility curve?

• under = undersaturated

• on = saturated

• over = supersaturated

how does pressure affect the solubility of a gas in liquid? name an example

the higher pressure of a solution, the higher the solubility will be

how do ions disassociate in high solubility ionic solutions?

disassociates into two ions, written as (aq)

how do ions disassociate in low solubility ionic solutions?

ions do not disassociate, solid precipitate is created, written as (s)

do molecular solutions disassociate?

no

how do particles seperate in high solubility covalent solutions?

dissolve (s => aq), but do NOT disassociate

how do ions disassociate in low solubility ionic solutions?

does not disassociate OR dissolve, written as (s)

what types of molecular solutions are high solubility?

• anything with H-bonds (H-F, H-N, H-O)

• sugars (have C, H, O)

what types of molecular solutions are low solubility?

anything without H-bonds

ionization

disassociation in acids

how do ions ionize in strong acids?

they ionize completely, into a hydrogen ion and an anion, shows as (aq)

what are the six strong acids?

• HCl

• HNO3

• H2SO4

• HClO4

• HI

• HBr

how do ions ionize in weak acids?

they do not ionize fully (about 50%), shows as whole molecules (aq)

how do elements disassociate?

• some elements are soluble in water, but they NEVER show as ions!

• s → s, or s → aq

what is written in (aq) in a total ionic equation?

• electrolytes (acids, bases, soluble ionic)

what is written in (s) in a total ionic equation?

• nonelectrolytes (molecular, insoluble ionic)

• precipitate

• gases