Topic 7: Acid, Bases & Salts Flashcards
How do acids react with metals?
Acids react with some metals to produce a salt and hydrogen gas
Write the word and chemical equation of the reaction between magnesium and sulfuric acid.
magnesium + sulfuric acid —-> magnesium sulfate + hydrogen
Mg + H2SO4 —–> MgSO4 + H2
Write the word and chemical equation of the reaction between iron and sulfuric acid.
iron + sulfuric acid —–> iron sulfate + hydrogen
Fe + H2SO4 ——-> FeSO4 + H2
Name two types of bases.
Metal oxides
Alkalis
How do bases react with acids?
When they react with acids, a neutralisation reaction occurs.
Write the word and symbol equation for the reaction between sulfuric acid and potassium hydroxide.
sulfuric acid + potassium hydroxide —-> potassium sulfate + water
H2SO4 (aq) + 2KOH (aq) ——-> K2SO4 (aq) + 2H2O (l)
Write the word ans symbol equation for the reaction between hydrogen bromide and magnesium hydroxide.
hydrogen bromide + magnesium hydroxide ——-> magnesium bromide + water
Mg(OH)2 (aq) + 2HBr (aq) ——–> MgBr2 (aq) + 2H2O (l)
How do acids react with metal carbonates?
They react to from a salt, water and carbon dioxide.
Write the word and symbol equation for the reaction between nitric acid and sodium carbonate.
Write the word and symbol equation for the reaction between calcium carbonate and sulfuric acid.
How do ammonium salts and alkalis react?
They react to produce salt, water and ammonia.
NaOH and KOH can be used as strong alkalis for this reaction to occur.
Write the word and symbol equation for the reaction between ammonium chloride and sodium hydroxide.
Tell me the colour of blue litmus in acids.
Red
Tell me the colour of blue litmus in alkalis.
Blue
Tell me the colour of methyl orange in acids.
Red
Tell me the colour of methyl orange in alkalis.
Yellow
Tell me the colour of thymolphthalein in acids.
colourless
Tell me the colour of thymolphthalein in alkalis.
Blue
Tell me the colour of phenolphthalein in acids.
Colourless
Tell me the colour of phenolphthalein in alkalis
Pink
Tell me the colour of red litmus in acids.
Red
Tell me the colour of red litmus in alkalis
Blue
Define base.
A substance that can react with acids and neutralise them
Give examples of bases.
Metal oxides, metal hydroxides and metal carbonates
Are bases soluble?
Many bases are insoluble but if a base does dissolve in water we call it an alkali
Give examples of alkalis.
sodium hydroxide
potassium hydroxide
aqueous ammonia
Tell me the difference between bases and alkalis.
Bases do not dissolve in water but bases that dissolve in water are alkali
All bases are not alkali but all alkalis are bases
Bases neutralise acids while alkalis release OH- ions (a proton acceptor)
What happens when acids are in water?
They dissociate to form H+ ions.
What are acids?
proton donors
What are alkalis?
proton acceptors
What are strong acids?
Acids that have a low ph (0-3) and fully dissociate into H+ ions in water
Give examples of strong acids.
Hydrochloric acid
Sulfuric acid
Nitric acid
What are weak acids.
Acids that have a higher pH (4-6) and partially dissociate into H+ ions in water
Give examples of weak acids.
Ethanoic acid
Citric acid
Carbonic acid
Are strong acids good conductors of electricity?
Yes
Are weak acids poorer conductors of electricity?
Yes
What is the pH a measure of?
the concentration of H+ ions in a solution
What pHs do acids have?
A pH < 7
What pHs do alkalis have?
a pH > 7
What is a pH 7?
A neutral pH
What are basic oxides?
Oxides that can neutralise an acid.
Metals react with oxygen to form basic oxides
Give examples of basic oxides.
Copper (II) oxide
Iron (III) oxide
Magnesium oxide
What are acidic oxides.
Oxides that dissolve to form acids
Non-metals react with oxygen to form acidic oxides
Give examples of acidic oxides.
Carbon dioxide
Sulfur dioxide
Phosphorus pentoxide
What are amphoteric oxides?
An oxide that reacts with both acids and alkalis
Give examples of amphoteric oxides.
aluminium oxide
zinc oxide
Write the symbol equation for the reaction between sodium hydroxide and aluminium oxide.
Al2O3 + 6NaOH —–> 2Na3AlO3 + 3H2O
What are neutral oxides?
Oxides that don’t react with acids or bases
Give examples of neutral oxides.
Carbon monoxide
Dinitrogen oxide
Tell me the solubility rules.
- All nitrates are soluble in water
- All chlorides, bromides and iodides are soluble in water, except those of lead and silver
- All sulfates are soluble in water except barium, calcium and lead sulfates
- All carbonates are insoluble, except those of potassium, ammonium and sodium
- All hydroxides are insoluble, except sodium, potassium and ammonium and calcium (partially)
