acid and alkali

Question 1

are acids and alkai’s on the same side of the ph scale

Answer 1

no, they are on opposite sides

Question 2

what are acids

Answer 2

substances that form hydrogen ions (H+) when they dissolve in aqueous soutions

Question 3

what are alkalis

Answer 3

substances that form hydroxide ions (OH-) when they dissolve in aqueous solutions

Question 4

name a type of base

Answer 4

an alkali

Question 5

what is the ph scale sued for

Answer 5

to measure how acididic or alkaline a substance is

Question 6

why does mixing an acid and alkali create a neutral substance

Answer 6

1. acids form hydrogen ions when they dissolve in water
2. alkalis form hydroxide ions when they dissolve in water
3. H+ and OH- ions combine to form H2O
4. water is a neutral substance, so an acid an alkai neutralise each other

Question 7

what does ionise mean

Answer 7

become ions

Question 8

what is the strength of an acid determined by

Answer 8

how much it ionises in water

Question 9

is the strength of an acid the same as the concentraction of an acid

Answer 9

NO

Question 10

what does it mean strong acids are fully ionised in water

Answer 10

all of the acid molecules break up to form H+ ions

Question 11

what are examples of strong acids

Answer 11

sulfric acid and nitric acid

Question 12

what is the equation for hydrochloric aicd

Answer 12

HCL -> H+ + CL-

Question 13

what does it mean by weak acids only partially ionise in watrr

Answer 13

not all of the acid molecules break up to form H+ ions

Question 14

are most acids weak or strong acids

Answer 14

weak acids

Question 15

what does the concentration of an acid mean

Answer 15

how many moles of H+ ions are in a unit volume

Question 16

what does the strength of the acid mean

Answer 16

how much of the acid ionises in watrer

Question 17

what ph do acids have

Answer 17

less than 7

Question 18

the lower the number on the ph scale the stronger the…

Answer 18

acid

Question 19

what do acids neutralise

Answer 19

alkali

Question 20

what do acids react with to produce salt

Answer 20

hydrogen

Question 21

what neutralises the acidic food that leaves the stomach

Answer 21

bile

Question 22

why is it important that bile neutralises acidic food that leaves the stomach

Answer 22

enzymes in the small intestine operate optimally in alkali condiitons and could therefore become denatrued in the absensce of bile

Question 23

what ph number is neautral

Answer 23

7

Question 24

what ph do strong acids have

Answer 24

close to zero

Question 25

what ph do alkali's have

Answer 25

more than 7

Question 26

what do ph do strong alkali have

Answer 26

a ph close to 14

Question 27

why is the ionisation of a weak acid a reversible reaction

Answer 27

only a few of the acid particles release H+ ions so equllibrium lies to the left

Question 28

if the ph goes down one, what happens to the concentration

Answer 28

increase by x10

Question 29

name examples of weak acids

Answer 29

ethanoic, ciric and carbonic acid

Question 30

if you have a large proportion of acid moleulces, what will they do to release H+ ions

Answer 30

dissociate

Question 31

if you have a small propotopn of the acid moleucles, what do they have to do to release H+ ions

Answer 31

dissociate

Question 32

name 5 kinds of indicators `

Answer 32

1. universal indicator 2. ph probe connected to a ph meter 3. phenolpthalein 4.methyl orange 5. litmus

Question 33

what colour does an alkali solution turn when phenolpthaline used

Answer 33

pink acid

Question 34

what colour does an acidic solution turn when phenopthalein is used

Answer 34

colourless

Question 35

what colour does an alkaline solution turn when methyl orange is used

Answer 35

yellow

Question 36

what colour does an acidic solution turn when methyl orange ix used

Answer 36

red

Question 37

what colour does an acidic solution turn when litmus colution is used

Answer 37

red

Question 38

what colour does an alkaline solution turn when litmus solution used

Answer 38

blue

Question 39

what colour does an acidic solution turn when blue litimus paper is used

Answer 39

red

Question 40

what colour does an alkaline solution turn when blue litmus paper is used

Answer 40

blue

Question 41

what colour does the acidic solution turn when red litimus paper is used

Answer 41

red

Question 42

what colour does an alkaline solution turn when red litmus paper is used

Answer 42

blue

Question 43

as ph decreases by one unit, what happens to the H+ concentration

Answer 43

increases by factor x10

Question 44

what does it mean when an acid in solution, has a high conc of H+ ions

Answer 44

the solution is more acidic, therefore ph is lower

Question 45

what does it mean if an alkali solution has a higher conc OH- ions

Answer 45

solution is more alkaline, thereofre higher ph

Question 46

the stronger the acid, the greater the dissociation...

Answer 46

the more H+ ions released and the lower ph

Question 47

how to react an acid and base to obstain a insouble salt

Answer 47

1. pour dilute acid into a beaker 2. leave the beaker to heat on bunsen 3. add base into dilute acid 4. do this until no more of the base will dissolve 5. take it off the bunsen 6. filter it using a funnel and filter paper 7. put the excess into a water batj 8. once crystals starts to from 9. filter it using filter paper and a funnel 10. leave it to dry

Question 48

acid + metal oxide

Answer 48

salt and water

Question 49

acid + metal carbonate

Answer 49

salt, water and carbon dioxide

Question 50

acid + metal hydroxide

Answer 50

salt + water

Question 51

acid + metal

Answer 51

salt and hydrogen gas

Question 52

what does insoulbe mean

Answer 52

a substance can't dissolve in watrr

Question 53

what does soulubles mean

Answer 53

a substance can dissolve in water

Question 54

are nitrates soulube arer insolube

Answer 54

soluble

Question 55

are chlorides solube or insolube

Answer 55

solube, excpet for silver and lead chloride

Question 56

are sulafates soluble

Answer 56

yes except lead barium and calcium sulfate

Question 57

are cstbonsyrd snf hydroxides soluble or insoulbe

Answer 57

insouble, except sodoium potassium ammonia

Question 58

are pottassium ammonia and sodium soluble or insouble

Answer 58

solubele