Answer:
Step-by-step explanation:
Sn + 2HBr = SnBr₂ + H₂
Here HBr is an acid but Sn is not a base . It is a metal . So it is not an acid - base reaction .
HCl + KOH = KCl + H₂O
HCl is an acid and KOH is a base so it is an acid base reaction.
2AlCl₃ + 3Ca(OH)₂ = 2Al(OH)₃ + 3CaCl₂
It is an acid base reaction . It is so because aluminium hydroxide is a lewis acid and calcium hydroxide is a base . So it is an acid base reaction .
2C₂H₆ +7O₂ = 4CO₂ + 6H₂O
It is not an acid base reaction . It is actually an example of oxidation reaction in which ethane burns in oxygen to give carbon dioxide and water.