Answer:
Zn(s) + CuSO4(aq) -----> ZnSO4(aq) + Cu(s)
Na2CO3 (aq)+ 2AgClO4(aq) → 2NaClO4(aq) + Ag2CO3(s)
2Al(s) + 6HI(aq) ------> 2AlI3(aq) + 3H2(g)
C12H22O11(s)+H2O(l)→4C2H5OH(aq)+4CO2(g)
2K(s) + 2H2O(l) ------->2KOH(aq) + H2(g)
Explanation:
In the first reaction, zinc displaces copper from an aqueous copper II salt since zinc is higher than copper in the electrochemical series.
Reaction two leads to the precipitation of silver carbonate. Remember that carbonates are mostly insoluble in water.
Acids are known to displace hydrogen gas from dilute acids. Hence in the third reaction, aluminum displaced hydrogen from aqueous hydroiodic acid.
In the fourth reaction, the action of yeast leads to the fermentation of sucrose yielding ethanol and carbon dioxide in the process.
Metals are known to form aqueous alkaline solutions liberating hydrogen gas when they react with water. Hence potassium metal reacts with water to liberate hydrogen gas and form alkaline potassium hydroxide.