In a certain electroplating process, gold is deposited onto an electrode. Describe the steps and calculations required to determine the mass of gold deposited if the current and time are known.
To determine the mass of gold deposited during electroplating when current and time are known: (1) Convert time to seconds; (2) Calculate total charge using Q = current (A) × time (s); (3) Use Faraday's constant (96,485 C/mol e⁻) to find moles of electrons transferred; (4) Use the balanced half-reaction to relate moles of electrons to moles of gold deposited; (5) Convert moles of gold to mass using gold's molar mass.
What is the SI unit for electrical current used in electroplating calculations?
The SI unit for electrical current is the ampere (A), which is equal to one coulomb per second.
In electroplating, which electrode do electrons travel toward?
Electrons travel from the anode to the cathode during electroplating.
What conversion must be made if time is given in hours or days for electroplating calculations?
Time must be converted to seconds before using it in electroplating calculations.
How is total charge calculated in an electroplating process?
Total charge is calculated by multiplying the current (in amperes) by the time (in seconds).
What constant is used to convert charge to moles of electrons in electroplating stoichiometry?
Faraday's constant, which is 96,485 coulombs per mole of electrons, is used for this conversion.
When starting with mass in an electroplating problem, what is the first conversion step?
The first step is to convert grams of the substance to moles using its atomic mass.
What role do coefficients in the balanced chemical equation play in electroplating calculations?
Coefficients are used to relate moles of electrons transferred to moles of the element being plated.
After finding moles of the plated substance, what are some units you can convert to?
You can convert moles to grams, molecules, ions, or kilograms depending on what is required.
If you know the charge and current in an electroplating process, how do you find the time required?
Divide the total charge (in coulombs) by the current (in amperes) to find the time in seconds.