Acids

Question 1

What is the colour of methyl orange in an acid?

Answer 1

Red

Question 2

What is the colour of methyl orange in a neutral solution?

Answer 2

Orange

Question 3

What is the colour of methyl orange in an alkali?

Answer 3

Yellow

Question 4

What is the colour of universal indicator in an acid?

Answer 4

Red - strong acid
Orange
Yellow -weak acid

Question 5

What is the colour of universal indicator in a neutral solution?

Answer 5

Green

Question 6

What is the colour of universal indicator in an alkali?

Answer 6

Blue - weak alkali
Purple - strong alkali

Question 7

What is the colour of phenolphthalein in acid?

Answer 7

Colourless

Question 8

What is the colour of phenolphthalein in a neutral solution?

Answer 8

Colourless

Question 9

What is the colour of phenolphthalein in an alkali?

Answer 9

Pink

Question 10

What is the colour of red litmus paper in acid?

Answer 10

Red

Question 11

What is the colour of red litmus paper in a neutral solution?

Answer 11

Red

Question 12

What is the colour of red litmus paper in an alkali?

Answer 12

Blue

Question 13

What is the colour of blue litmus paper in acids?

Answer 13

Red

Question 14

What is the colour of blue litmus paper in a neutral solution?

Answer 14

Blue

Question 15

What is the colour of blue litmus paper in an alkali?

Answer 15

Blue

Question 16

What is the hydrochloric acid formula

Answer 16

HCl

Question 17

What is the sulphuric acid formula?

Answer 17

H₂SO₄

Question 18

What is the nitric acid formula?

Answer 18

HNO₃

Question 19

What is the potassium hydroxide formula?

Answer 19

KOH

Question 20

What is the lithium hydroxide formula?

Answer 20

LiOH

Question 21

Describe a neutralisation reaction

Answer 21

When the right amount of acid and the right amount of alkali is added together to make a neutral solution

Question 22

What is the general formula for a neutralisation reaction?

Answer 22

Acid + alkali ——> water + salt

Question 23

What do all acids contain?

Answer 23

Positive hydrogen ions (H+ ions)

Question 24

The stronger the acid, the more __ ____ it has.

Answer 24

H+ ions

Question 25

What do all alkalis contain?

Answer 25

Negative hydroxide ions (OH- ions)

Question 26

The stronger the alkali is, the more ___ ____ it has.

Answer 26

OH- ions

Question 27

What is the ionic equation for a neutralisation reaction?

Answer 27

H⁺ + OH^- ——> H₂O

Question 28

What salts do hydrochloric acid produce?

Answer 28

Metal chlorides

Question 29

What salts do sulphuric acids produce?

Answer 29

Metal sulphates

Question 30

What salts do nitric acid produce?

Answer 30

Metal nitrates

Question 31

Sulphuric acid + lithium hydroxide ——> ???

Answer 31

Sulphuric acid + lithium hydroxide ——> lithium sulphate + water

Question 32

Nitric acid + sodium hydroxide ——> ???

Answer 32

Nitric acid + sodium hydroxide ——> sodium nitrate + water

Question 33

Hydrochloric acid + aluminium hydroxide ——> ???

Answer 33

Hydrochloric acid + aluminium hydroxide ——> aluminium chloride + water

Question 34

What is a concentrated acid?

Answer 34

An acid with a high proportion of acid molecules in it

Question 35

What is a dilute acid?

Answer 35

An acid with a low proportion of acid molecules in it

Question 36

What is a strong acid?

Answer 36

An acid that completely ionises (dissociates) in water, this means they separate into ions

Question 37

What is a weak acid?

Answer 37

An acid that only partially ionises (dissociates) in water, this means that some of the acid separates into ions and some stay as the acid

Question 38

Give an example of a strong acid dissociating

Answer 38

HCl ——> H+Cl-

Question 39

Magnesium + oxygen ——> ???

Answer 39

Magnesium oxide

Question 40

Silver + sulphur ——> ???

Answer 40

Silver sulphide

Question 41

Tin + oxygen ——> ???

Answer 41

Tin oxide

Question 42

Nickel + sulphur + oxygen ——> ???

Answer 42

Nickel sulphate

Question 43

Potassium + nitrogen + oxygen ——>???

Answer 43

Potassium nitrate

Question 44

What is the overall charge of a compound?

Answer 44

0

Question 45

Acid + metal ——> ???

Answer 45

Salt + hydrogen

Question 46

Acid + metal oxide ——> ???

Answer 46

Salt + water

Question 47

Acid + metal hydroxide ——> ???

Answer 47

Salt + water

Question 48

Acid + metal carbonate ——> ???

Answer 48

Salt + water + carbon dioxide

Question 49

What is the test for carbon dioxide?

Answer 49

If a limewater solution goes cloudy when gas is put in, then carbon dioxide is present (Could also use lit splint and if it goes out in the gas then carbon dioxide could be present, but other gasses would also do the same)

Question 50

What is the test for oxygen?

Answer 50

Oxygen will always relight a glowing splint

Question 51

Describe titration

Answer 51

- **Measure out the alkali** using a pipette, put it into a **conical flask** with a few drops of an **indicator** eg. Phenolphthalein - Place the conical flask on top of a **white tile**, to make it easy to see the colour change - **Fill a burette with acid**, using a funnel, then remove the funnel and record your starting volume of acid.

Question 52

Describe the concentration of H+ ions in an acid as it becomes more acidic

Answer 52

Increases

Question 53

Describe the concentration of H+ ions in an acid as it becomes more alkali

Answer 53

Decreases

Question 54

What is a cation?

Answer 54

An ion that is positively charged

Question 55

What is an anion?

Answer 55

An ion that is negatively charged

Question 56

What is the formula for magnesium sulphate?

Answer 56

MgSO₄

Question 57

What is the formula for sodium hydroxide?

Answer 57

NaOH