How long must a current of 1.20 A pass through a sulfuric acid solution in order to produce 25.0 mL of H2 gs at 25 degrees C and 1 atm pressure?
moles H2: PV/RT solve that.
Now for the charge per H2 molecule
H2SO4+2H2O>>2H2 + O2 + H2SO4
Each O loses two electrons, so each O2 loses 4 electrons, so then 2H2 gains 4 electrons, so each mole of H2 gains 2*avag number of electrons.
Now, what charge is that?
charge=chargeoneOneElectron*2*avagnumber
= 1.6E-19*2*6.12E23= ....
current*timeinSeconds= charge above
solve for time.
To determine how long a current of 1.20 A must pass through a sulfuric acid solution to produce 25.0 mL of H2 gas at 25 degrees C and 1 atm pressure, we need to use Faraday's law and the ideal gas law.
1. First, we need to calculate the moles of H2 gas produced using the ideal gas law:
PV = nRT
Here, P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.
Since the volume is given in mL, we need to convert it to liters (L) by dividing by 1000:
V = 25.0 mL / 1000 = 0.025 L
We know the pressure is 1 atm and the temperature is 25 degrees Celsius, which needs to be converted to Kelvin:
T = 25 + 273 = 298 K
Plugging in these values, the equation becomes:
(1 atm)(0.025 L) = n(0.0821 L.atm/mol.K)(298 K)
Simplifying:
0.025 atm.L = 24.4038 n
n ≈ 0.0010254 mol (moles of H2 gas)
2. Next, we can use Faraday's law to determine the amount of charge (Q) required to produce this amount of H2 gas.
Faraday's law states that the amount of charge required (Q) is equal to the product of current (I), time (t), and the Faraday constant (F):
Q = I * t * F
The Faraday constant (F) is approximately 96,485 C/mol.
We are given the current (I) as 1.20 A, so we can rearrange the equation to solve for time (t):
t = Q / (I * F)
Plugging in the values:
t = (0.0010254 mol * 96,485 C/mol) / (1.20 A * 1 C/A)
Simplifying:
t ≈ 837 seconds or 13.95 minutes
Therefore, a current of 1.20 A must pass through the sulfuric acid solution for approximately 13.95 minutes to produce 25.0 mL of H2 gas at 25 degrees C and 1 atm pressure.