Acids and Bases

Question 1

what are the 5 physical properties of an acid?

Answer 1

1) sour taste
2) turns damp blue litmus paper red (no effect on red litmus paper)
3) pH less than 7
4) turns Universal Indicator from green to yellow/orange/red (depends on pH)
5) good conductor of electricity (due to mobile ions)

Question 2

what are the 4 chemical properties of an acid?

Answer 2

1) acid + reactive metal —> salt + hydrogen
2) acid + metal carbonate —> salt + carbon dioxide + water
3) acid + base —> salt + water
4) only produce H+ ions in aqueous solutions (not organic solvents) which gives their acidic properties

Question 3

what are metals that cannot be used to react with acids?

Answer 3

unreactive: copper, silver, gold
too reactive: Group I, barium, calcium

Question 4

what are the 5 physical properties of an alkali?

Answer 4

1) bitter taste, soapy feel
2) turns damp red litmus paper blue (no effect on blue litmus paper
3) pH more than 7
4) turns Universal Indicator from green to blue/violet (based on pH)
5) good conductor of electricity (due to mobile ions)

Question 5

what are the 2 chemical properties of an alkali?

Answer 5

1) alkali + acid —> salt + water
2) alkali + ammonium salt —> salt + ammonia + water

Question 6

name 3 strong acids

Answer 6

hydrochloric acid
sulfuric acid
nitric acid

Question 7

name 4 weak acids

Answer 7

phosphoric acid
carbonic acid
citric acid
acetic/ethanoic acid

Question 8

name 2 strong alkalis

Answer 8

sodium hydroxide
potassium hydroxide

Question 9

name 1 weak alkali

Answer 9

aqueous ammonia

Question 10

what are characteristics of basic oxides?

Answer 10

• most metallic oxides are basic
• insoluble (excludes Group I)
• neutralises with acids

Question 11

what are characteristics of amphoteric oxides?

Answer 11

• only zinc ~, aluminium ~, lead(II) ~
• insoluble in water
• neutralises with both acids and bases

Question 12

what are characteristics of acidic oxides?

Answer 12

• most non-metallic oxides are acidic
• often gaseous at room temp.
• most soluble in water to form acids
• neutralises with alkalis

Question 13

what are 5 acidic oxides and their acids?

Answer 13

1) sulfur dioxide (sulfurous acid)
2) sulfur trioxide (sulfuric acid)
3) carbon dioxide (carbonic acid)
4) nitrogen dioxide (nitric acid)
5) phosphorus(V) oxide (phosphoric acid)

Question 14

what are characteristics of neutral oxides?

Answer 14

• very few non-metallic oxides are neutral (water, carbon monoxide, nitrogen oxide)
• insoluble
• does not react with acids or bases