Electrolysis and Molar Mass Concepts

This tutorial covers electroplating and electrolysis, focusing on calculating the mass of metals plated on a cathode using electric current and time. It includes examples with nickel, copper, iron, and an unknown metal, demonstrating how to determine the required current, time, and identify metals through molar mass. The video also explains the electrolysis of sodium hydroxide, calculating the volume of oxygen gas produced.

What is the first step in calculating the mass of nickel plated onto the cathode?

• Determine the number of moles of electrons

• Calculate the molar mass of nickel

• Find the cell potential

• Convert time from minutes to seconds

How many moles of electrons are required to plate one mole of copper?

• Four moles

• Three moles

• Two moles

• One mole

What is the molar mass of copper used in the calculation?

• 63.55 g/mol

• 55.85 g/mol

• 58.69 g/mol

• 65.38 g/mol

What is the molar mass of iron used in the calculation?

• 63.55 g/mol

• 58.69 g/mol

• 55.85 g/mol

• 65.38 g/mol

How long does it take to plate 10 grams of iron using a 5 amp current?

• 1.5 hours

• 1.9 hours

• 2.1 hours

• 2.5 hours

What is the charge of the unknown metal in the electrolysis problem?

• Minus two

• Minus one

• Plus two

• Plus one

Which metal was identified as the unknown metal based on its molar mass?

• Zinc

• Nickel

• Lead

• Copper

What is produced at the cathode during the electrolysis of sodium hydroxide?

• Sodium metal

• Chlorine gas

• Hydrogen gas

• Oxygen gas

What is the volume of oxygen gas produced at the anode at STP when a 5 amp current is applied for 45 minutes?

• 784 mL

• 700 mL

• 500 mL

• 600 mL

What is the standard volume occupied by one mole of gas at STP?

• 22.4 liters

• 24.0 liters

• 18.0 liters

• 20.0 liters