Chapter 6: Acid and Alkali

Question 1

What is acid?

Answer 1

A substance that produces hydrogen ions when dissolved in water.

Question 2

Does ion have positive or negative charge?

Answer 2

Both, there are positive ion and negative ion.

Question 3

How does acid tastes?

Answer 3

Sour

Question 4

What is the pH value of acid?

Answer 4

<7

Question 5

Reaction of litmus paper with acid.
Red?
Blue?

Answer 5

Red→red

Blue→blue

Question 6

Does acid react with metal?

Answer 6

Yes, they produces hydrogen gas.

Question 7

What will happen if alkali and acid combine?

Answer 7

Neutralises and forms salt and water.

Question 8

What is organic acid.

Answer 8

An acid found in living things that contains carbon and is usually weak acid that is less corrosive

Question 9

What acid does citrus fruits have?

Answer 9

Citric acid.

Question 10

What acid do apples have?

Answer 10

Malic acid

Question 11

What acid do grapes have?

Answer 11

Tartaric acid

Question 12

What acid does tea have?

Answer 12

Tannic acid

Question 13

What acid does Vineger have?

Answer 13

Acetic acid

Question 14

What acid does yogurt have?

Answer 14

Lactic acid

Question 15

What acid does bees and ants have?

Answer 15

Formic acid.

Question 16

What is an inorganic acid?

Answer 16

Inorganic acid is obtained from mineral salt which is usually strong acid and more corrosive, also known as mineral acids.

Question 17

Give 3 examples of inorganic acid.

Answer 17

• Sulphuric acid
• Hydrochohloric acid
• Carbonic acid

Question 18

What is alkali?

Answer 18

A substance that produces hydroxide ions when dissolved in water.

Question 19

Are all bases alkali?

Answer 19

All alkalis are bases but not all bases are alkali.

Question 20

Name the alkali of potassium oxide + Water.

Answer 20

Potassium hydroxide.

Question 21

Name the alkali of sodium oxide + Water.

Answer 21

Sodium hydroxide

Question 22

Name the alkali of calcium oxide + Water.

Answer 22

Calcium hydroxide

Question 23

How does alkali tastes?

Answer 23

Bitter

Question 24

How does it feel when touching alkali?

Answer 24

Slippery

Question 25

Reaction of litmus paper with alkali. Red? Blue?

Answer 25

Red→Blue | Blue→Blue

Question 26

Does alkali react with metal?

Answer 26

No

Question 27

Does alkali react with ammonium salt?

Answer 27

Yes, it releases ammonia gas when heated together with it.

Question 28

What is alkali mostly used for?

Answer 28

Making almost all cleaning items.

Question 29

Name the scientific names of these alkalis. Caustic soda Lime water Ammonia solution

Answer 29

Caustic soda - sodium hydroxide Lime water - calcium hydroxide Ammonia solution - ammonium hydroxide

Question 30

When does alkali and acid show their properties?

Answer 30

Acid and alkalis only show their properties in the presence of water.

Question 31

How to find whether a substance is acidic or alkaline? (5)

Answer 31

Tested by: - red/blue litmus paper - Universal indicator - Phenolphthalein - Methyl orange

Question 32

How to spell the indicator that is pink in alkali?

Answer 32

Phe-nol-ph-tha-le-in

Question 33

What is the coulour of acids and alkalines in a pH colour chart?

Answer 33

Red-more acid Blue/Purple- more alkaline pH chart macam like rainbow colour

Question 34

Which is the best indicator and state it's form.

Answer 34

Universal indicator, liquid form

Question 35

What will happen if methyl orange be dipped in alkaline?

Answer 35

Become yellow.

Question 36

What will happen if methyl orange be dipped in neutral?

Answer 36

yellow

Question 37

What will happen if methyl orange be dipped in acid?

Answer 37

red

Question 38

What will happen if phenolphthalein is dripped into acid?

Answer 38

colourless

Question 39

What will happen if phenolphthalein is dripped into alkaline?

Answer 39

pink

Question 40

What will happen if phenolphthalein is dripped into neutral?

Answer 40

colourless

Question 41

What will happen if universal indicator be dripped into acid?

Answer 41

red

Question 42

What will happen if universal indicator be dripped into alkaline?

Answer 42

Blue

Question 43

What will happen if universal indicator be dripped into neutral?

Answer 43

Green

Question 44

What is the use of acetic acid?

Answer 44

- Preserving food | - Flavouring food

Question 45

What is the use of absorbing acid?

Answer 45

To build up resistance to diseases (it is actually vitamin C)

Question 46

What is the use of boric acid?

Answer 46

-Preserve food

Question 47

What is the use of nitric acid?

Answer 47

To make fertilisers

Question 48

What is the use of tartaric acid?

Answer 48

To make cakes and bicuits (tartar powder)

Question 49

What is the use of aluminium hydroxide?

Answer 49

-Make gastric medicine and toothpaste

Question 50

What is the use of ammonium hydroxide?

Answer 50

-To make fertilisers

Question 51

What is the use of calcium hydroxide?

Answer 51

-Neutralising acidic soil

Question 52

What is the use of magnesium hydroxide?

Answer 52

Making milk of magnesia | → for people who needs gastric juice

Question 53

What is the use of potassium hydroxide?

Answer 53

-Make soap and paint removers

Question 54

What is neutralisation?

Answer 54

A chemical reaction between an acid and an alkali to form a salt and water

Question 55

What is the format in writing the name of combined alkali and acid?

Answer 55

(Alkali) (acid with changed tense)

Question 56

What is the name of hydrochloric acid + sodium hydroxide?

Answer 56

Sodium chloride + water

Question 57

How to achieve neutralisation? (labotary)

Answer 57

Titration

Question 58

What is titration?

Answer 58

Titration is a process where an acid is gradually added from a burrete to an alkali until the end point of neutralisation is reached.

Question 59

What is the end point of titration?

Answer 59

The end point is reached when an indicator that has been added to the alkali changes colour.

Question 60

What is usually used as an indicator in titration?

Answer 60

phenophthelein and universal indicator.

Question 61

What does the burette contain in titration?

Answer 61

acid

Question 62

What does the flask at the bottom contain in titration?

Answer 62

alkali and the indicator.

Question 63

How can toothpaste help us?

Answer 63

Toothpaste which is alkaline help to neutralise the acid produced by bacteria acting on the food stuck between the teeth.

Question 64

What is the answer key in the application of neutralisation in life?

Answer 64

must include both words alkaline and acid .