acids bases and salts

Question 1

what are acids?

Answer 1

proton donors,
ph<7

Question 2

what are bases?

Answer 2

proton acceptor
substance that neutralises an acid
ph>7

Question 3

do alkalis dissolve in water?

Answer 3

yes

Question 4

sulfuric acid symbol

Answer 4

H2SO4

Question 5

sulfate salt symbol and charge

Answer 5

SO4 2-

Question 6

hydrochloric acid symbol

Answer 6

HCL

Question 7

chloride symbol and charge

Answer 7

CL -

Question 8

nitric acid symbol

Answer 8

HNO3

Question 9

nitrate symbol and charge

Answer 9

NO3 -

Question 10

what solutions contain H+ ions

Answer 10

aqueos solutions of acids

Question 11

what do aqueous solutions of alkalis contain

Answer 11

OH- ions

Question 12

what happens when an acid reacts with a metal

Answer 12

salt and hydrogen are given off

Question 13

what happens when a metal oxide reacts with bases

Answer 13

salt and water are formed

Question 14

what happens when an acid reacts with a metal hydroxide

Answer 14

salt and water formed

Question 15

what happens wen an acid reacts with a metal carbonate

Answer 15

salt, water, and carbon dioxide formed

Question 16

what happens when an acid reacts with ammonia

Answer 16

ammonium slat formed

Question 17

what color does litmus paper turn with an acid and then with an alkali

Answer 17

acid= red
alkali=blue

Question 18

thymolphthalein color when with acid and then with alkali

Answer 18

acid= colourless
alkali=blue

Question 19

methyl orange turn with acid and with alkali

Answer 19

acid=red
alkali-yellow

Question 20

phenolphthalein color with acid and alkali

Answer 20

acid= colourless
alkali=pink

Question 21

universal indicator turns what colour with alkali and acid

Answer 21

alkaline= blue (weak) purple (strong)
acid= orange(weak) red (strong)

Question 22

what is a strong acid

Answer 22

acid that completly dissociates in aqueous solution

Question 23

what is a weak acid

Answer 23

acid that partially dissociates in aqueous solution

Question 24

are non-metal oxides more likely to be acidic or basic
give an example

Answer 24

acidic
CO2 AND SO2

Question 25

are metal- oxides more likely to be acidic or basic give example

Answer 25

basic CuO and CaO

Question 26

color of magnesium oxide

Answer 26

white powder

Question 27

colour of iron oxide

Answer 27

red/orange

Question 28

colour of copper oxide

Answer 28

black powder

Question 29

what oxides are neutral

Answer 29

carbon monoxide and dinitrogen oxide

Question 30

what does it mean for an oxide to be amphoteric

Answer 30

be both acidic and basic, can react with either to produce a salt and water

Question 31

examples of amphoteric acids

Answer 31

aluminium oxide and zinc (II) oxide

Question 32

difference between bases and alkalis

Answer 32

bases are oxides or hydroxides of metals and alkalis are soluble bases, not all bases are alkalis all alkalis are bases

Question 33

describe how you would make a soluble salt using an insoluble base

Answer 33

1-heat up an acid until nearly boiling 2-add excess of a base and mix 3-filter excess to remove residue, and what is left is only the salt 4- add solution to an evaporating basin and heat until crystals are seen in edge 5-let cool for a few days

Question 34

when making a soluble salt using an insoluble base how would you know that all acid has been neutralised?

Answer 34

you should use an excess of the base and you should see this excess on the bottom of the flask

Question 35

how do these salts form crystals?

Answer 35

they are in regular arrangement of positive and negative ions forming a cube/ ionic lattice

Question 36

how can you decide once you have created a saturated solution of a given salt

Answer 36

when crystals are seen in edge of evaporating basin

Question 37

why is it not advisable to heat the crystals to dryness during the crystallisation process?

Answer 37

they could thermally decompose

Question 38

what does the term saturated solution mean?

Answer 38

no more solute can dissolve in solution anymore has reaches solubility limit

Question 39

what happens when an acid and an alkali react? also explain with equation.

Answer 39

OH- + H+ ---> H2O water is produced is a neutralization reaction

Question 40

explain how to produce salts by titration steps

Answer 40

1.in a burette measure an acid until 0cm3 2.use a volumetric pipette to measure 25cm3 of alkali 3.add alkali to a conical flask and add the phenolphthalein indicator (turns pink) 4.add acid and mix flask until solution turns colourless 5.measure amount of acid needed to neutralize alkali 6.repeat expirment without indicator 7.put solution in evaporating basin and heat gently until crystals are seen in edge 8.leave drying for a few days

Question 41

how do you make insoluble salts?

Answer 41

by precipitation

Question 42

what salts are soluble?

Answer 42

all sodium potassium and ammonium all nitrates chloride salts except silver chloride and lead (II) chloride sulfate salts except calcium, barium and lead (II) sulfate

Question 43

what salts are insoluble?

Answer 43

all carbonates except sodium potassium and ammonium all hydroxides except sodium pottasium ammonium and partially calcium exceptions: silver chloride, lead sulfate, calcium sulfate, lead chloride and barium sulfate

Question 44

how do you prepare insoluble salts step by step.

Answer 44

1. salts that are insoluble in water form a percipitate which is a insoluble chemical formed in a chemical reaction 2.mix two soluble salts together, they will swap partners and a soluble and an insoluble salt are formed 3. to do this mix both soluble salts together, and a percipitsate will form, filter and what is left in the filter paper is the insoluble salt

Question 45

formula for number of moles

Answer 45

mass/ mr

Question 46

formula for concentration of a solution

Answer 46

number of moles/ volume (in dm3)

Question 47

what is cm3 to dm3?

Answer 47

/1000

Question 48

what is dm3 to cm3

Answer 48

x1000

Question 49

how do you convert mol/dm3 to g/dm3?

Answer 49

mol/dm3 x mr

Question 50

what is a hydrated substance?

Answer 50

a substance that is chemically combined with water

Question 51

what is an anhydrous substance?

Answer 51

a substance containing no water

Question 52

whats meant by the term water of crystallisation?

Answer 52

water molecules present in hydrated crystals

Question 53

what happens when bases react with ammonium salts

Answer 53

salt, ammonia and water are produced

Question 54

why is hydrochloric acid a strong acid (equation)

Answer 54

HCL--> H + CL

Question 55

why is ethanoic acid a weak acid (equation)

Answer 55

CH3COOH <------>H + CH3COO

Question 56

what is formula of ammonium salt

Answer 56

NH4+

Question 57

what happens when a base reacts with an acid

Answer 57

create a salt and water