A current of 4.5A passed through a gold salt for 1h45min,(a) calculate the mass of gold deposited(b) calculate the number of mole of gold deposited
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current of 4.5A passed through a gold salt for 1h45min,(a) calculate the mass of gold deposited(b) calculate the number of mole of gold deposited
To calculate the mass of gold deposited, you can use Faraday's law of electrolysis. According to this law, the mass of a substance deposited during electrolysis is directly proportional to the amount of charge passed through the electrolyte. The formula for calculating the mass of a substance deposited is:
mass = (charge * molar mass) / (Faraday's constant)
a) To calculate the mass of gold deposited, we first need to calculate the charge passed through the electrolyte. Since current is given in amperes and time is given in hours, we need to convert the time to seconds:
1 hour = 60 minutes
1 minute = 60 seconds
Converting 1 hour 45 minutes to seconds:
1 hour 45 minutes = (1 hour * 60 minutes/hour) + 45 minutes
= (60 minutes) + 45 minutes
= 105 minutes
= 105 minutes * 60 seconds/minute
= 6300 seconds
Now we can calculate the charge passed using the formula:
charge = current * time
charge = 4.5 A * 6300 s
= 28350 C
Next, we need to find the molar mass of gold. The molar mass of gold is 197 g/mol.
molar mass = 197 g/mol
Finally, we can calculate the mass of gold deposited:
mass = (charge * molar mass) / Faraday's constant
Faraday's constant is 96485 C/mol.
mass = (28350 C * 197 g/mol) / 96485 C/mol
= 576.682 g
b) To calculate the number of moles of gold deposited, we can use the formula:
moles = mass / molar mass
moles = 576.682 g / 197 g/mol
= 2.928 mol
Therefore, the mass of gold deposited is 576.682 grams (rounded to three decimal places), and the number of moles of gold deposited is 2.928 moles (rounded to three decimal places).
To calculate the mass of gold deposited, you need to use the equation that relates current, time, and the amount of substance deposited. This equation is known as Faraday's Law of Electrolysis.
(a) Calculate the mass of gold deposited:
Step 1: Convert the given time into seconds.
1 hour = 60 minutes
45 minutes = 45/60 = 0.75 hours
Total time = 1 hour + 0.75 hours = 1.75 hours
Total time in seconds = 1.75 hours * 60 minutes/hour * 60 seconds/minute = 6300 seconds
Step 2: Use Faraday's Law of Electrolysis to calculate the mass of gold deposited.
Faraday's Law states that the mass of substance deposited is directly proportional to the current and directly proportional to the time. The proportionality constant is known as the electrochemical equivalent, which is specific to the substance being deposited. For gold, the electrochemical equivalent is 197.0 g/C.
Mass of gold deposited = Current * Time * Electrochemical equivalent
= 4.5 A * 6300 s * (197.0 g/C)
= 4.5 * 6300 * 197.0 g
= 5,579,950 g (rounded to the nearest whole number)
Therefore, the mass of gold deposited is 5,579,950 grams (or 5.58 kg, rounded to two decimal places).
(b) To calculate the number of moles of gold deposited, we need to use the molar mass of gold.
The molar mass of gold (Au) is 196.97 g/mol.
Number of moles of gold deposited = Mass / Molar mass
= 5,579,950 g / 196.97 g/mol
= 28,309.24 mol (rounded to two decimal places)
Therefore, the number of moles of gold deposited is approximately 28,309.24 moles.