Please Help me solve this question
If 0.22grams of a divalent metal is deposited when a current of 0.45ampere is passed through a solution of a salt for 25 minutes. Using appropriate electrodes, calculate the relative atomic mass of the metal. (Faraday=96500)
How many Coulombs do you have? That's
C = A x seconds = 0.45 x 25 min x 60 s/min = about 675
96,500 C will deposit M/2 g of the metal where M is the atomic mass.
So M/2 x 675/96,500 = 0.22
M = ? = atomic mass of the element.
0.222g of a divalent metal is deposited when a current of 0.45 ampere is passed through a solution of its sought of 25mins.calculate the relative atomic mass of its metal
yes
To calculate the relative atomic mass of the metal, we need to use Faraday's laws of electrolysis.
Faraday's first law states that the amount of a substance deposited during electrolysis is directly proportional to the quantity of electricity passed through the electrolyte.
The formula to calculate the amount of substance (in grams) deposited is:
Amount (in grams) = (Current in Amperes * Time in seconds) / (Faraday's constant)
Given:
- Current (I) = 0.45 Amperes
- Time (t) = 25 minutes = 25 * 60 seconds = 1500 seconds
- Faraday's constant (F) = 96500 C/mol (Coulombs per mole)
Let's calculate the amount of substance deposited:
Amount (in grams) = (0.45 A * 1500 s) / 96500 C/mol
Amount (in grams) = 0.006985grams
Since we know the atomicity of the metal is 2 (divalent), we need to divide the amount by 2 to get the amount of one mole:
Amount (in grams) per mole = 0.006985grams / 2
Amount (in grams) per mole = 0.0034925grams
Now, we calculate the relative atomic mass (RAM) using the equation:
RAM = (Amount (in grams) per mole) / (Avogadro's constant)
Avogadro's constant (NA) = 6.022 × 10^23 mol^-1
RAM = 0.0034925grams / (6.022 × 10^23 mol^-1)
RAM = 5.8 × 10^-27 grams/mol
Therefore, the relative atomic mass of the metal is approximately 5.8 × 10^-27 grams/mol.