One way that safety enters into specifications is to specify the composition of a vapor in air that could burn if ignited. If the range of concentration of benzene in air in which ignition could take place is 1.4 to 8.0 percent, what would be the corresponding temperatures for air saturated with benzene in the vapor space of a storage tank? The total pressure in the vapor space is 100 kPa.

To determine the corresponding temperatures for air saturated with benzene in the vapor space of a storage tank, you need to use the concept of the flammability limit and the relationship between temperature, pressure, and saturation.

Here's how you can calculate the corresponding temperatures:

Step 1: Determine the partial pressure of benzene in the air.

The concentration range of benzene in air is given as 1.4% to 8.0%. To calculate the corresponding partial pressure, you can use the formula:

Partial Pressure of Benzene = Concentration of Benzene * Total Pressure

When the concentration is given as a percentage, you need to convert it to a decimal:

Lower Concentration (C₁) = 1.4% = 0.014
Upper Concentration (C₂) = 8.0% = 0.08

Partial Pressure at Lower Concentration (P₁) = C₁ * Total Pressure = 0.014 * 100 kPa = 1.4 kPa
Partial Pressure at Upper Concentration (P₂) = C₂ * Total Pressure = 0.08 * 100 kPa = 8.0 kPa

Step 2: Use Antoine's equation to calculate the corresponding temperatures.

Antoine's equation relates the vapor pressure of a substance to its temperature. The equation is generally given as:

log(P) = A - (B / (T+C))

Where:
P = Vapor pressure in kPa
T = Temperature in °C
A, B, and C are constants specific to the substance

For benzene, the following Antoine's equation constants can be used:
A = 4.01866
B = 1171.53
C = -53.778

Rearranging the equation, you can solve for temperature (T):

T = (B / (A - log(P))) - C

Using the lower and upper partial pressures calculated in Step 1, you can now calculate the corresponding temperatures:

For the lower concentration:
T₁ = (B / (A - log(P₁))) - C

For the upper concentration:
T₂ = (B / (A - log(P₂))) - C

Simply substitute the values of P₁ and P₂ in the equations to find the corresponding temperatures (T₁ and T₂).