One type of breathalyzer employs a fuel cell to measure the quantity of alcohol in the breath. When a suspect blows into the breathalyzer, ethyl alcohol is oxidized to acetic acid at the anode:

CH3CH2OH(g)+4OH−(aq)→HC2H3O2(g)+3H2 O(l)+4e−

At the cathode, oxygen is reduced:
O2(g)+2H2O(l)+4e−→4OH−(aq)

The overall reaction is the oxidation of ethyl alcohol to acetic acid and water. When a suspected drunk driver blows 186 mL of his breath through this breathalyzer, the breathalyzer produces an average of 320 mA of current for 10 s.

Required:
Assuming a pressure of 1.0 atm and a temperature of 26C, what percent (by volume) of the driver's breath is ethanol?

The percent of ethanol is 0.1093%

Explanation:

Given:

t = time = 10 s

I = current = 320 mA

F = Faraday's constant = 96485.3365 C mol⁻¹

n = number of electrons = 4

Molecular weight of ethanol = 46 g/mol

Question: What percent (by volume) of the driver's breath is ethanol, %E = ?

First, it is necessary to calculate the mass of ethanol:

The moles of ethanol:

Applying the equation of ideal gas:

Here:

T = 26°C = 299 K

P = 1 atm

Substituting values:

The percent of ethanol:

%

if two electrons have the same n, the same ℓ, and the same ml, then they are in the same orbital. the pauli exclusion principle states that no two identical fermions (a fancy word for electrons and other subatomic particles like electrons) may occupy the same quantum state in an atom simultaneously.

i just learnt this recently but i need to look through my notes again