Acids And Alkalis

Question 1

What are the three key acids you need to know?

Answer 1

Hydrochloric acid = HCl
Sulfuric acid = H2SO4
Nitric acid = HNO3

Question 2

Acid + metal —> ??

Answer 2

Salt + hydrogen

Question 3

Acid + alkali —> ???

Answer 3

Salt + water

Question 4

Acid + metal carbonate —> ????

Answer 4

Salt + water + carbon dioxide

Question 5

Acid + metal oxide —> ???

Answer 5

Salt + water

Question 6

Acids have a pH less than _____

Answer 6

7

Question 7

Bases have pH more than _____

Answer 7

7

Question 8

Give some examples of bases

Answer 8

Alkali, metal oxide, metal carbonate

Question 9

What are alkalis?

Answer 9

Bases that are water soluble

Question 10

Give some examples of alkalis:

Answer 10

Lithium hydroxide, sodium hydroxide, potassium hydroxide.

Question 11

When is it more suitable to use a paper indicator rather than a liquid indicator?

Answer 11

To test for gases.

Question 12

What colour would litmus paper in an acidic reaction?

Answer 12

Red

Question 13

What colour would litmus paper turn in blue?

Question 14

What colour does methyl orange turn in acidic solutions?

Answer 14

Red

Question 16

What colour does methyl orange turn in alkali solutions

Answer 16

Yellow

Question 17

What colour does phenolphthalein turn in acidic solutions?

Answer 17

Colourless

Question 18

What colour does phenolphthalein turn in alkali solutions?

Answer 18

Bright pink

Question 19

How would you use universal indicator to determine the approximate pH value of something?

Answer 19

It shows a range of colours between different strengths of acids and alkalis.

Question 20

True of false: alkalise can neutralise acids.

Answer 20

True

Question 21

What are the solubility rules?

Answer 21

• common sodium, potassium, and ammonium compounds are soluble
• all nitrates are soluble
• common chlorides are soluble except, sliver and lead (II)
• common sulfate are soluble except: barium, calcium, and lead (II)
• common carbonates are insoluble, except: sodium, potassium, and ammonium compounds
• common hydroxides are insoluble except: sodium, potassium, calcium.

Question 22

What is neutralisation?

Answer 22

Reaction between acid and bases water is formed.

Question 23

What is an acid?

Answer 23

An acid in an aqueous solution is a source of hydrogen ions (H+). An acid is a proton donor.

Question 24

What is an alkali?

Answer 24

An alkali in an aqueous solution is a source of hydroxide ions (OH-).

Question 25

What is a base?

Answer 25

A base is a proton acceptor, soluble bases are alkalis which are sources of OH-.

Question 26

Describe the reaction between hydrochloric acid and magnesium.

Answer 26

Effervescence, metal disappears.

Question 27

Describe the reaction between hydrochloric acid and black copper oxide (metal oxide).

Answer 27

Green solution formed, copper oxide disappears.

Question 28

Describe the reaction between hydrochloric acid and sodium hydroxide (metal hydroxide).

Answer 28

Colourless solution formed, test tube feels warm, exothermic reaction.

Question 29

Describe the reaction between hydrochloric acid and calcium carbonate (metal carbonate).

Answer 29

Effervescence, metal disappears.

Question 30

What are the charges for zinc, silver, lead?

Answer 30

Lead (ll) = 2+ Silver = + Zinc = 2+

Question 31

What can act as a base in a chemical reaction?

Answer 31

Metal oxides, metal hydroxides, and ammonia can act as bases.

Question 32

How does an oxide compound form?

Answer 32

Elements react with oxygen in the air to form oxides. They react more vigorously with pure oxygen.

Question 33

What observations from a substance being burnt in oxygen tells us info about its pH?

Answer 33

After being tested with universal indicator to determine the pH, non metals lean more acidic, and metals lean more alkali.

Question 34

How do you determine a substances solubility?

Answer 34

Amount (g) of substance which can dissolve in 100 (ml) of water at a given temperature.

Question 35

What is a solute?

Answer 35

Substance which dissolved in a solvent to form a solution.