Answer:
concentration of air = 0.0000366 ppm is not sufficient to cause any eye irritation
Explanation:
Average amount of aldehyde generated by a cigarette = 1 mg = 10⁻⁶g
Room volume = Height * Base area
Room volume = 8ft * 1200 sq.ft = 9600 cubic feet
number of people in the room = 23
If 1 person smokes 2 cigarette in 1 hour,
23 people will smoke 23*2 cigarettes = 46 cigarettes in 1 hr
Mass of aldehyde generated by 1 cigarette = 10⁻⁶g
Mass of aldehyde generated by 46 cigarettes = 46 * 10⁻⁶g
Based on the law of mass conservation,
Mass of aldehyde coming in = mass of aldehyde going out = Rate of accumulation of aldehyde
Rate of accumulation of aldehyde in the steady state = 0
m*C*V= 0
m = 46 * 10⁻⁶g
C = concentration in the steady state
V = Volumetic flow of the fresh air
V = 600 ft³/min = 600 *60
V = 36000 ft³/hr
Density = Mass/volume
Density = 46 * 10⁻⁶g /36*10³
Density = 1.28 * 10⁻⁹ g/ft³
If the density of air is taken as 36 g/ft³
concentration = (1.28 * 10⁻⁹ g/ft³)/36 g/ft³
concentration = 3.66 * 10⁻¹¹g/g
1*10⁻⁶g/g of air = 1ppm(part per million)
concentration of air =( 3.66 * 10⁻¹¹)(/1*10⁻⁶)
concentration of air = 3.66 * 10⁻⁵ppm = 0.0000366 ppm
concentration of air = 0.0000366 ppm is not sufficient to cause any eye irritation