How many grams of hydrogen can be produced by the electrolysis of water with a current of 0.290 A running for 5.00 min?
To determine the number of grams of hydrogen produced by the electrolysis of water, you need to follow a few steps.
Step 1: Calculate the total charge used during electrolysis.
The formula to calculate the charge (Q) is given by:
Q = I * t
where I represents the current in amperes and t represents the time in seconds.
In the given problem, the current is 0.290 A, and the time is 5.00 min (which is equal to 300 seconds).
Therefore, Q = 0.290 A * 300 s = 87 C (Coulombs)
Step 2: Determine the number of moles of electrons transferred.
The Faraday's law of electrolysis relates the number of moles of electrons (n) to the charge (Q) by the equation:
n = Q / F
where F represents the Faraday constant, equal to 96,485 C/mol.
In this case, n = 87 C / 96,485 C/mol ≈ 9.01 x 10^-4 mol
Step 3: Convert moles of electrons to moles of hydrogen gas.
Since two moles of electrons are required to produce one mole of hydrogen gas (H2) according to the balanced equation of water electrolysis, the number of moles of hydrogen gas produced is half the number of moles of electrons.
Therefore, the moles of hydrogen gas = 9.01 x 10^-4 mol / 2 = 4.50 x 10^-4 mol
Step 4: Convert moles of hydrogen gas to grams.
The molar mass of hydrogen gas is about 2 g/mol.
Thus, the mass (m) is given by:
m = moles * molar mass
m = 4.50 x 10^-4 mol * 2 g/mol = 9 x 10^-4 g
Therefore, approximately 9 x 10^-4 grams of hydrogen can be produced by the electrolysis of water with a current of 0.290 A running for 5.00 min.