Chapter 23: Acids, Bases, and Salts

common bases

house cleaning products, antacid, fertilizer `

neutralization

a chemical reaction between an acid and a base that takes place in a water solution

salt formation

a compound formed when the negative ions from an acid combine with the positive ions from a base

salts are composed of

a positive metal ion and an ion with a negative charge, such as Cl-

titration

a solution of known concentration is used to determine the concentration of another solution

acids

a substance that produces hydrogen ions in a water solution. When an acid dissolves in water H+ ions interact with water molecules to form H3O+ ions, hydronium ions.

acid-base reaction

acid+base----> salt+water

ammonia

ammonia is a base that does not contain -OH, in a water solution, dissociation takes place when the ammonia molecule attracts a hydrogen ion from a water molecule, forming an ammonium ion (NH4+) this leaves a hydroxide ion (OH-)

bases

any substance that forms hydroxide ions,OH-, in water solution, any substance that accepts H+ from acids

ions

can conduct an electric current, the more ions a solution contains the more current it can conduct

common acids

citric acid, stomach acid, fertilizer

neutralization + salt formation

half of the ions in the solution react to form water and half form salt

H+

hydrogen

H3O

hydronium

OH-

hydroxide

properties of bases

in a pure, undissolved state, many bases are crystalline solids, feel slippery, bitter taste, corrosive, cause burns, turns litmus paper blue

esters

made from acid and water is formed in the reaction used to prepare them, come from alcohols that are not bases but have a hydroxyl group

strong acid

nearly all the acid molecules dissociate into ions ex: nitric acid, hydrochloric acid, sulfuric acid

weak acid

only a small fraction of the molecules dissolve in water ex: acetic acid and carbonic acid

soaps

organic salts, have a nonpolar organic chain of carbon atoms on one end and either a sodium or potassium salt of a carboxylic,-COOH, group at the other end. the nonpolar,hydrocarbon end interacts with oils and first so that they can be removed readily and the ionic end helps them dissolve in water

neutral

pH of 7, indicates that the concentrations of H+ ions and OH- ions are equal

strong and weak

refers to the ease with which an acid or base dissociates in a solution

uses for esters

soaps, perfumes, flavors, clothing

buffers

solutions containing ions that react with additional acids or bases to minimize their effects on pH ex: buffers help keep your blood close to a nearly constant pH of 7.4

acidic

solutions with a pH lower than 7, the lower the value is, the more acidic

basic

solutions with pH greater than 7, the higher the value is, the more basic

properties of acids

sour taste, can cause painful burns, corrosive, turns litmus paper red

pH

the measure of the concentration of H+ (hydrogen) ions in it, the greater the H+ concentration is, the lower the pH is and the more acidic the solution is

how titration happens

the standard solution (known concentration) is added slowly and carefully to a solution of unknown concentration to which an acid/base indicator has been added. If the solution of unknown concentration is a base, a standard acid solution is used. If the unknown is an acid, a standard base solution is used.

dilute and concentrated

used to indicate the concentration of a solution, which is the amount of acid or base dissolved in a solution

example of neutralization

when HCI is neutralized by NaOH, hydronium ions from the acid combine with hydroxide ions from the base to produce neutral water

dissociation of acids

when an acid dissolves in water, the negative areas of nearby water molecules attract the positive hydrogen in the acid, the acid dissociates or separates into ions and the hydrogen atom combines with a water molecule to form hydronium ions (H3O+)

dissociation of bases

when bases that contain -OH dissolve in water, the negative areas of nearby water molecules attract the positive ion in the base, the base dissociates into a positive and negative ion- a hydroxide ion (OH-), unlike acid dissociation, water molecules do not combine wth the ions formed from the base