Topic 4 - Acids and Alkalis

Question 1

what pH does the strongest acid have?

Answer 1

0

Question 2

what pH does the strongest alkali have?

Answer 2

14

Question 3

what pH does a neutral substance have?

Answer 3

7

Question 4

how does universal indicator change colour depending on pH?

Answer 4

its red in acidic solutions, green in a neutral solution and purple in an alkaline solution

Question 5

how does litmus paper change colour depending on pH?

Answer 5

its red in acidic solutions, purple in neutral solutions and blue in alkaline solutions

Question 6

how does phenolphthalein change colour depending on pH?

Answer 6

it turns pink in alkaline solutions

Question 7

how does methyl orange change colour depending on pH?

Answer 7

its red in acidic solutions and yellow in alkaline solutions

Question 8

what are acids a source of?

Answer 8

hydrogen ions (H+)

Question 9

acids are proton…

Answer 9

donors

Question 10

what is a base?

Answer 10

a substance that can neutralise an acid

Question 11

bases are proton…

Answer 11

acceptors

Question 12

what are alkalis?

Answer 12

soluble bases

Question 13

what is an alkali a source of?

Answer 13

hydroxide ions (OH-)

Question 14

what is a reaction between an acid and a base called?

Answer 14

neutralisation

Question 15

how is neutralisation seen in H+ and OH- ions?

Answer 15

H+ + OH- = H₂O

Question 16

how is neutralisation seen in terms of proton transfer?

Answer 16

the acid donates protons which are accepted by the base