Response:The ethanol percentage is 0.1093%
Explanation:
As given:
t = time = 10 s
I = current = 320 mA
F = Faraday's constant = 96485.3365 C mol⁻¹
n = number of electrons transferred = 4
Molecular weight of ethanol is 46 g/mol
Question: What is the percent (by volume) of ethanol in the driver's breath, %E =?
First, calculate the ethanol mass:

The moles of ethanol:

Applying the ideal gas law formula:

Here:
T = 26°C = 299 K
P = 1 atm
Substituting in the values:

The percentage of ethanol:
%
The visual representation is displayed in the following image.
For calculations, consider 100 grams of the compound:
ω(Cl) = 85.5% ÷ 100%.
ω(Cl) = 0.855; signifying the mass percentage of chlorine in the compound.
m(Cl) = 0.855 · 100 g.
m(Cl) = 85.5 g; this represents the mass of chlorine.
m(C) = 100 g - 85.5 g.
m(C) = 14.5 g; indicating the mass of carbon.
n(Cl) = m(Cl) ÷ M(Cl).
n(Cl) = 85.5 g ÷ 35.45 g/mol.
n(Cl) = 2.41 mol; this is the quantity of chlorine.
n(C) = 14.5 g ÷ 12 g/mol.
n(C) = 1.21 mol; this is the quantity of carbon.
n(Cl): n(C) = 2.41 mol: 1.21 mol = 2: 1.
The compound in question is identified as dichlorocarbene CCl₂.
The correct answer is Option A.
The calculation goes as follows:
Number of millimoles of Na3PO4 = 1 × 100 = 100
Number of millimoles of AgNO3 = 1 × 100 = 100
Dissociating 1 mole of Na3PO4 yields 3 moles of sodium ions and 1 mole of phosphate ions, whereas 1 mole of AgNO3 releases 1 mole of Ag+ and 1 mole of NO3-.
The Ag+ ion concentration becomes negligible since it forms a precipitate with the phosphate ion, indicating that the concentration of phosphate ions is also low.
With 100 millimoles of Na3PO4, we get 300 millimoles of Na+ and 100 millimoles of PO43-, and with 100 millimoles of AgNO3 we have 100 millimoles of Ag+ and 100 millimoles of NO3-.
Thus, the order of increasing concentration is: PO43- < NO3- < Na+.