Question

A student drops pieces of potassium and silver in beakers containing water.

The image shows the reaction. What are the products formed in each beaker?


a) Beaker 1: K2O and H2O; Beaker 2: AgO and H2O

(b) Beaker 1: KOH and H2O; Beaker 2: Ag2O and H2O

(c) Beaker 1: K2O and H2O; Beaker 2: No reaction takes place

(d) 1: KOH and H2O; Beaker 2: No reaction takes place​

Answer 1

The products formed in each beaker are - (d) 1: KOH and H₂; Beaker 2: No reaction takes place​.

When sodium is dropped into the beaker.

• Potassium can react even with cold water as follows to form potassium oxide and hydrogen gas is liberated.
• This is a very violent and exothermic reaction such that the liberated hydrogen gas catches fire.

$2K+2H_{2}O \rightarrow 2KOH+H_{2}$

• Thus, one of the products is KOH and H₂.

When silver is dropped into the beaker.

• Only the elements above hydrogen in the reactivity series can displace hydrogen in a chemical reaction.
• Since silver lies below hydrogen, it does not react with water at all.
• Thus, in the second case, no reaction takes place at all.

Answer 2

Answer:

d

Explanation: