Flashcards in Acids, bases and neutralisation Deck (7)
What are acids?
- Acids are proton donors as they release hydrogen ions when mixed with water.
H2SO4 + H2O = 2H(+) + SO4(2-)
- Strong acids completely dissociates by releasing all Hydrogen atoms in aqueous solution:
HCl -> H(+) + Cl(-)
- Weak acids partially dissociates as only small proportion of hydrogen atoms are released as ions in aq. solutions:
CH3COOH <=> H(+) + CH3COOH(-)
<=> equilibrium sign indicates that forward reaction is incomplete.
Bases and alkalis
- Bases neutralise acid to form salts.
- Alkali is a base that dissolves in water and releases Hydroxide ions (OH-) in solution:
NaOH -> Na(+) + OH(-)
- General formula of neutralisation reaction is:
Acid + Base -> Salt + Water
H(+) + OH(-) -> H2O
Products of neutralisation
- Acid + METAL -> salt + hydrogen
- Acid + metal OXIDE* -> salt + water
- Acid + metal CARBONATE** -> salt + water = carbon dioxide
* reaction of metal hydroxide is the same as metal oxide ** reaction of metal hydrogen carbonate is the same as metal carbonate
Charges of some ions
NO3(-), HCO3(-), Ethanoate: CH3COO(-)
Partial and complete neutralisation reactions of carbonic acid w/ sodium hydroxide
NaOH + H2CO3 -> NaHCO3 + H2O
2NaOH + H2CO3 -> Na2CO3 + 2H2O