acids and bases

Question 1

Arrhenius theory

Answer 1

acids ionise and form hydrogen ions,

bases dissociate in water to form hydroxide ions

Question 2

Brønsted-Lowry theory

Answer 2

a substance behaves as an acid when it donates a proton to a base.
a substance behaves as a base when it accepts a proton from an acid

Question 3

Acids are

Bases are

Answer 3

proton donors

proton acceptors

Question 4

An acid-base reaction involves

Answer 4

an exchange of protons from an acid to a base

Question 5

HCl added to water

water/HCl acted as

Answer 5

it breaks apart to form hydronium ion and chlorine ion.

HCl acted as an acid bc has donated hydrogen ion to eater. Water acted as a base bc accepted a proton from HCl

Question 6

HCl hydrolysis reaction

HCL dissociation reaction

Answer 6

HCl(g)+H2O(l)–> H3O+(aq) +Cl-(aq)

HCl(g)+H2O(l)–> H+(aq) +Cl-(aq)

Question 7

Hydrolysis reaction

Answer 7

occurs when a molecule/ion in an aqueous solution reacts with water either by accepting or donating a proton

Question 8

Advantages of BL theory

Answer 8

acids and bases not restricted to aqueous solutions

Question 9

Limitations of BL theory

Answer 9

cannot be applied to run b/w acidic and basic oxides
under certain conditions solid calcium oxide (basic oxide) reacts with gaseous CO2 (acidic oxide) to produce salt calcium carbonate
CaO(s) +CO2(g)–> CaCO3(s)

Question 10

Conjugate acid-base pairs

Answer 10

are 2 species that differ by a proton

Question 11

Conjugate acid of a base

Answer 11

contains 1 more H+ ion (proton) than the base

Question 12

Conjugate base of an acid

Answer 12

contains 1 less H+ ion (proton) than the acid

Question 13

HCl(g)+H2O(l)–> H3O+(aq) +Cl-(aq)
Acid/base/conj?
(((HCl(g)+H2O(l)–> H+(aq) +Cl-(aq)))

Answer 13

HCl acid
Cl- acids conj base
water base
H3O+ bases conj acid

Question 14

Amphiprotic

Answer 14

substances that can behave as either an acid or a base (water)

Question 15

Amphiprotic substances Examples

Answer 15

H2O, H2PO4-, HSO4-, CO3^2-, HCO3-,HPO4^2-, H2SO4

Question 16

Monoprotic acid

Answer 16

donate 1 proton per molecule

ethanoic acid

Question 17

acidic proton

Answer 17

the hydrogen atom that is donated by and acid

Question 18

polyphonic acid
diprotic
triprotic

Answer 18

can donate more than 1 proton per molecule(in steps)
can donate 2 protons
3 protons

Question 19

Strong acid (def)

Answer 19

will readily donate a proton (ionise)
donate protons easily
solution of strong acid contains ions with virtually no unreacted acid molecules present

Question 20

Weak acid

Answer 20

Only ionises partially
ethnic acid (CH3COOH), carbonic acid (H2CO3), phosphoric acid (H3PO4)

Question 21

Strong acid examples

Answer 21

hydrochloric acid (HCl), sulphuric acid(H2SO4), Nitric acid(HNO3)

Question 22

Strong bases

Answer 22

accept protons easilt
sodium hydroxide (naOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2)

Question 23

Weak bases

Answer 23

only accept a small portion of protons

ammonia (NH3)

Question 24

Acidity constant (Ka)

Answer 24

the equilibrium constant for a hydrolysis reaction of an acid
Ka= [H3O+][CH3COO-]/[CH3COOH]
water not included

Question 25

Basicity constant (Kb)

Answer 25

symbol given to eq constant for a hydrolysis rxn of a base | more???

Question 26

Concentrated and dilute

Answer 26

describe the amount of acid or base dissolved in a given V of solution

Question 27

what do Ka indicate

Answer 27

the strength of an acid

Question 28

Pure water undergoes

Answer 28

``` self ionisation (to a small extent) H2O(l)+H2O(l) H3O+(aq)+ OH(aq)- ```

Question 29

Ionic product (ionisation constant) of water

Answer 29

Kw=[H3O+][OH-]=1.00 x 10^-14 @25ºC

Question 30

pH

Answer 30

a scale that is a way of expressing the levels of acidity | pH=-log10[H3O+]

Question 31

[H3O+]=

Answer 31

[H3O+]= 10^-pH

Question 32

Kw and temperature

Answer 32

T will affect value of Kw. As Temp increases so does the value of Kw which lowers pH This is bc self ionisation of water is endothermic

Question 33

dilution

Answer 33

mixing concentrated acid with water

Question 34

Salts

Answer 34

are ionic compounds containing a positive ion (cation) other than a hydrogen ion (H+) or a negative ion(anion) other than oxide ion (O^2-) or (OH-)

Question 35

Salts formed from?

Answer 35

neutralisation rxn by combination of acid and base | has cation from base and anion from acid

Question 36

A dissociation reaction (salts) takes place

Answer 36

when salt dissolves in water | The cation/anion produced may react with water to produce either H3O+ or OH- ions

Question 37

Neutral salts

Answer 37

salts produced in reaction between strong acid and strong base the anion and cation do not react with water

Question 38

Salts of strong acid and weak base

Answer 38

are acidic bc the conj acid of weak base hydrolyses to form hydronium ions

Question 39

Acidic salt

Answer 39

a salt produced in rxn between strong acid and weak base | the anion/cation of acidic salt reacts with water by donating proton

Question 40

Salts of weak acid and strong base

Answer 40

are basic salts bc anions hydrolyse to form hydroxide ions

Question 41

basic salt

Answer 41

a salt produced in rxn b/w weak acid and strong base | anion/cation of basic salt reacts with by accepting proton

Question 42

salt of weak acid and weak base

Answer 42

involves 2 competing hydrolysis reactions The conj base of weak acid reacts w/ water to form H3O+ The conj acid of weak base reacts w/ water to form OH-

Question 43

The pH of a solution of a salt of a weak acid and weak base

Answer 43

depends on the extent to which each rxn occurs

Question 44

Acid and base properties of common ions

Answer 44

Neutral (from strong acids+bases)= Cl- Br- NO3- Acidic (from weak bases)= NH4+,HSO4-, H2PO4- Basic(from weak acids)= CO3^2-, HPO4^2-, HCO3-, PO4^3-, SO4^2-, F-

Question 45

Determine acidity of salt produced by rxn of NaOH and phosphoric acid

Answer 45

NaOH+ H3PO4--> ect | PO4^3- basic ion so salt is basic

Question 46

Aqueous solutions of salts of polyprotic acid

Answer 46

can be neutral acidic or basic