acids and bases

Question 1

what are alkalis?

Answer 1

bases that will dissolve in water

Question 2

what is used to test acids and alkalis?

Answer 2

litmus

Question 3

what do acids and alkalis turn litmus?

Answer 3

acids- red

alkalis- blue

Question 4

what happens when an alkali and alkalis meet?

Answer 4

they neutralise each other

Question 5

what does the pH show?

Answer 5

how acidic or alkaline a substance is

Question 6

what does a pH of 0 mean?

Answer 6

shows a strong acid

Question 7

what does a pH of 14 mean?

Answer 7

a strong alkali

Question 8

what is a neutral pH?

Answer 8

7

Question 9

finish this sentence… acids have a pH of

Answer 9

less than 7

Question 10

finish this sentence… alkalis have a pH of

Answer 10

more than 7

Question 11

when is a base and alkali?

Answer 11

when it dissolves in water

Question 12

what is an alkali?`

Answer 12

just a soluble base

Question 13

give an example of a base that in not an alkali?

Answer 13

copper oxide

Question 14

what are the most common bases?

Answer 14

metal oxides and metal hydroxides

Question 15

what is the equation for the reaction of an acid and base?

Answer 15

acid+base—salt+water

Question 16

what do all acidic solutions contain?

Answer 16

hydrogen ions

Question 17

what is the unit for this?

Answer 17

H+

Question 18

what are indicators?

Answer 18

substances which change colour when pH changes

Question 19

when does an indicator such as litmus change colour?

Answer 19

suddenly at one pH value only

Question 20

when do indicators such as universal indicator change?

Answer 20

gradually over a range of different pH values

Question 21

what does an acid solution contain?

Answer 21

hydrogen ions, h+

Question 22

what are hydrogen ions responsible for?

Answer 22

the reactions of an acid

Question 23

what does an alkali solution contain?

Answer 23

hydrogen ions, OH-

Question 24

what happens when an acid neutralises an alkali?

Answer 24

the hydrogen ions react with the hydroxide to make water

Question 25

what is the equation for this?

Answer 25

H+OH- ---- H2O

Question 26

when a pH = 0 what does this mean?

Answer 26

it is very acidic

Question 27

when a pH is 14 what does this mean?

Answer 27

it is very alkaline

Question 28

explain what happens when an acid rises in the pH scale?

Answer 28

the ph at the start is low the ph rises as the alkali neutralises the acid neutral when more alkali is added the ph rises to 7

Question 29

explain what happens when an alkaline falls in the pH scale?

Answer 29

the ph is high the ph falls as the acid neutralises the alkali neutral when more acid is added the ph falls below 7

Question 30

what does an universal indicator show?

Answer 30

how acidic something is

Question 31

what is universal indicator?

Answer 31

a mixture of indicators, each one changing at a different ph

Question 32

what are the equations for metal oxides and hydroxides?

Answer 32

acid+oxide---salt+water | acid+hydroxide---salt+water

Question 33

what is the equation for the reaction between acid +carbonate?

Answer 33

acid + carbonate --- salt + water + carbon dioxide

Question 34

what is salt made from?

Answer 34

part of a base and part of an acid

Question 35

what is made when sodium hydroxide reacts with hydrochloric acid?

Answer 35

sodium chloride is formed

Question 36

where do nitrates come from?chlorides?sulfates?phosphates?

Answer 36

nitric acid hydrochloric acid sulfuric acid phosphoric acid