S3 Acids&Bases Flashcards
What gives acids their properties?
H+ ions
Define acid.
An acid is a substance which produces H+ ions when dissolved in water.
What is the difference in definition of strong acids and weak acids?
Strong acids dissolve completely in water while weak acids dissolve partially in water.
Name 3 physical properties of acids.
1) Has a sour taste
2) Turns damp BLUE litmus paper RED
3) Electrical conductivity(because of mobile ions)
Define salts.
A salt is a compound obtained when the hydrogen of an acid is partly or completely replaced by a METAL or an ammonium ion.
Define base.
A base is a metal oxide or hydroxide that reacts with an acid to form salt and water only.
What is neutralisation?
When a base reacts with an acid to form salt and water.
What happens when a base is soluble in water?
It will form an alkali.
Define alkali.
An alkali is a base which is soluble in water and produces HYDROXIDE ions in water.
What is the difference in definition between strong and weak alkalis?
Strong alkalis completely dissociate in water and produces high concentration of HYDROXIDE ions in water while weak alkalis partially dissociate in water to produce low concentration of HYDROXIDE ions.
Name 2 examples of a strong alkali.
NaOH and KOH
Name an examples of a weak alkali.
Ammonia solution
Name 5 properties of an alkali.
1) Bitter taste
2) turns damp RED litmus paper BLUE
3) Reacts with acid to form salt and water
4) Reacts with ammonium salts to form ammonia gas, salt and water
5) Conductor of electricity due to mobile ions
What is the color of Methyl orange in strong acids and strong alkalis?
acids - red
alkalis - yellow
What is the color or phenolphthalein in strong acids and strong alkalis?
acids - colorless
alkalis - pink
What is the color or screened methyl orange in strong acids and strong alkalis?
acids - violet
alkalis - green
Name 3 properties of basic oxides.
1) oxides of metals
2) Dissolve in water to form alkalis
3) React with acids to form salt and water only
How can oxides be classified?
Acidic oxides, basic oxides, amphoteric oxides, neutral oxides
Name 3 properties of acidic oxides.
1) oxide of non metals
2) dissolve in water to form acids
3) React with bases to form salts and water only
Name a property of neutral oxides.
Neither acidic or basic
Name 2 examples of basic oxides.
CaO, CuO
Name 4 examples of amphoteric oxides.
Al2O3, PbO, ZnO, SnO (tin)
Name 2 examples of acidic oxides.
CO2, SO2
Name 2 examples of neutral oxides.
Water, carbon monoxide
How do we apply acids/bases in real life?
If the soil is too acidic, it can be neutralized by adding Ca(OH)2 (slake lime) or CaO (quicklime, known as liming the soil.
What is a displacement reaction?
Acid+reactive metals=salt+hydrogen
What is a neutralization reaction
Acid+bases=salt+water
What are the products of an acid and carbonate reaction?
Salt, carbon dioxide and water
Name 2 uses of acid.
H2SO4 used for battery acids in cars and agriculture fertilizers.
Name 2 properties of amphoteric oxides.
1) metallic oxides which can behave as both acidic and basic oxides
2) form salts with both acids and alkalis.
Explain why it becomes more difficult to see the cross when an insoluble, colored product is formed.
The insoluble product does not dissolve in the solution. As the reaction progresses, more and more product particles are SUSPENDED in the solution, obscuring the cross thus making it harder to see the cross.
