Introduction:
When electricity is passed through a solution containing ions, the ions can undergo a process called electrolysis. Electrolysis involves the migration of ions towards the electrodes, where they can either get reduced (gain electrons) or oxidized (lose electrons). The amount of substance deposited or liberated at each electrode can be determined by Faraday's laws of electrolysis.

Faraday's Laws of Electrolysis:
1. The mass of a substance deposited or liberated during electrolysis is directly proportional to the quantity of electricity passed through the electrolyte.
2. The mass of different substances deposited or liberated by the same quantity of electricity is directly proportional to their respective chemical equivalents.

Applying Faraday's Laws:
To determine the ratio of moles of Ag, Cd, Al, and Pb deposited, we need to calculate the number of moles of each substance based on the amount of electricity passed through the electrolyte using Faraday's laws.

1. Silver (Ag):
The chemical equation for the reduction of Ag+ ions is:
2Ag+ + 2e- → 2Ag
From the equation, we can see that 2 moles of Ag ions are required for every 2 moles of electrons. Therefore, 1 mole of Ag is deposited for every 1 mole of electrons.
Since 1 Faraday of electricity corresponds to 1 mole of electrons, and 4 Faradays of electricity were passed, we can conclude that 4 moles of Ag will be deposited.

2. Cadmium (Cd):
The chemical equation for the reduction of Cd2+ ions is:
Cd2+ + 2e- → Cd
From the equation, we can see that 2 moles of Cd2+ ions are required for every 2 moles of electrons. Therefore, 1 mole of Cd is deposited for every 1 mole of electrons.
Since 1 Faraday of electricity corresponds to 1 mole of electrons, and 4 Faradays of electricity were passed, we can conclude that 4 moles of Cd will be deposited.

3. Aluminum (Al):
The chemical equation for the reduction of Al3+ ions is:
Al3+ + 3e- → Al
From the equation, we can see that 3 moles of Al3+ ions are required for every 3 moles of electrons. Therefore, 1 mole of Al is deposited for every 1 mole of electrons.
Since 1 Faraday of electricity corresponds to 1 mole of electrons, and 4 Faradays of electricity were passed, we can conclude that 4 moles of Al will be deposited.

4. Lead (Pb):
The chemical equation for the reduction of Pb4+ ions is:
Pb4+ + 4e- → Pb
From the equation, we can see that 4 moles of Pb4+ ions are required for every 4 moles of electrons. Therefore, 1 mole of Pb is deposited for every 1 mole of electrons.
Since 1 Faraday of electricity corresponds to 1 mole of electrons, and 4 Faradays of electricity were passed, we can conclude that 4 moles of Pb will be deposited.

Summary:
Based on the application of Faraday's laws of electrolysis, the ratio of moles of Ag, Cd, Al, and Pb deposited is 4:4:4: