Physical Science - Chapter 8

solution

homogeneous mixture, substance must dissolve within another substance

solute

the substance being dissolved

solvent

the part that does the dissolving, usually in greater quantity

dissociation

the process in which an ionic compound separates into ions as it dissolves

dispersion

the breaking into small pieces that spread throughout the solvent

dissolving

this takes place at the surface only

ionization

process in which neutral molecules gain or lose electrons, a chemical change results

conductivity

the ability of a substance to allow electrical charges to flow

freezing point

adding a substance that dissolves in water will lower water's __

boiling point

adding a solute to water also elevates (raises) water's __

exothermic reaction

release to surroundings

endothermic reaction

absorbs from surrounding

factors that affect the rate of dissolving

stirring, temperature, surface area

stirring

increases the collisions between the solute and solvent

temperature

causes particles to move faster and also creates collisions

surface area

refers to the area of contact between solute and solvent

solubility

the amount of solute that will dissolve in 100g of water at a specific temperature

saturated

a solution in which no more solute will dissolve within the given solvent, adding more solute will not result in dissolving

unsaturated

a solution that is capable of holding more solute within a given amount of solvent

supersaturated

solutions containing more solute than the solvent will allow

like dissolves like

this means polar solvents will dissolve polar solutes

temperature

generally an increase in the __ will increase the solubility of the substance (exception - gas in liquid)

pressure

increased __ will increase the solubility of gases and liquids (but it has little or no effect on the solubility of solids in liquids)

acid

any compound that produces hydronium ions (H30) when dissolved in water (contains hydrogen that ionizes

properties of acids

sour taste, reactivity with active metals, affects indicators, good conductors

solubility curves

graph that shows solubilities of substances over a range of temperatures

reactivity

active metals react with acids to produce hydrogen gas (corrosive)

indicators

substances that will change color in the presence of an acid or base (litmus)

sulfuric acid

(H2SO4), most widely used chemical, used in making of fertilizers, plastics and car batteries, dehydrating agent

hydrochloric acid

(HCl), stomach acid, used to clean rust from steel/iron

pickling

process that removes rust from steel/iron

nitric acid

(HNO3), uses include fertilizers and explosives (TNT)

strong acids

sulfuric acid, hydrochloric acid, nitric acid

weak acids

carbonic acid, acetic acid, hydrofluoric acid, ascorbic acid

carbonic acid

(H2CO3), found in pop

acetic acid

(CH3COOH or HC2H3O2), used in making vinegar

hydrofluoric acid

used to "etch" glass

ascoric acid

(H2C6H6O6), better known as vitamin C

two element acid

when naming this type of acid, add the word "hydro-" to the front - e.g. HCl - hydrochloric acid

three element acid

when naming this type of acid, go to the second element to name it - H2SO4 - Sulfuric acid

base

any compound that releases hydroxide ions (OH-1) when dissolved in water, dissociates

properties of bases

bitter taste, slippery feel, affects indicators, good conductors, caustic

caustic

means wears away animal fibers

strong base

sodium hydroxide

sodium hydroxide

(NaOH), commonly called lye

weak base

calcium hydroxide

calcium hydroxide

Ca(OH)2, used to neutalize acid soil, remove hair from animal hides

neutralization

reaction between an acid and a base

pH

the __ of a solution is a measure of the hydronium ion concentration

ways to determine the pH of a solution

pH paper, pH meter