A chemistry laboratory of an experience is being conducted. The pressure is 0.9 atm and the temperature is 18°C. One of the steps of the experience requires the combustion of 500 mL ethanol (Density=0.78 g/mL). Whereas the burning of this amount of ethanol does not significantly alter the conditions environments, but frees carbonic gas.Calculate the volume of CO2 generated (in L) and the concentration of carbon dioxide in the lab environment, in mol.L-1.

To calculate the volume of CO2 generated and the concentration of CO2 in the lab environment, we'll need to use the ideal gas law. The ideal gas law equation is:

PV = nRT

Where:
P = pressure (in atm)
V = volume (in liters)
n = moles of gas
R = ideal gas constant (0.0821 L.atm/mol.K)
T = temperature (in Kelvin)

First, we need to convert the temperature from Celsius to Kelvin:

T(K) = T(°C) + 273.15
T(K) = 18 + 273.15
T(K) = 291.15 K

Now, let's calculate the volume of CO2 generated:

1. Determine the moles of ethanol burnt:
To calculate the moles of ethanol, we need to know its mass. The density of ethanol is given as 0.78 g/mL, and we have 500 mL of ethanol. So, the mass of ethanol is:

Mass = Volume × Density
Mass = 500 mL × 0.78 g/mL
Mass = 390 g

Next, we convert the mass of ethanol to moles using its molar mass. The molar mass of ethanol (C2H5OH) is approximately 46.07 g/mol. So, the number of moles of ethanol is:

Moles = Mass / Molar mass
Moles = 390 g / 46.07 g/mol
Moles ≈ 8.47 mol

2. Calculate the moles of CO2 generated:
The balanced chemical equation for the combustion of ethanol is:

C2H5OH + 3O2 -> 2CO2 + 3H2O

From the equation, we can see that 2 moles of CO2 are produced for every mole of ethanol burnt. Therefore, the number of moles of CO2 generated is:

Moles of CO2 = 2 × Moles of ethanol
Moles of CO2 = 2 × 8.47 mol
Moles of CO2 ≈ 16.94 mol

3. Calculate the volume of CO2:

Now, using the ideal gas law equation, we can calculate the volume of CO2 at the given conditions. Let's substitute the values into the equation:

PV = nRT

V = (nRT) / P
V = (16.94 mol × 0.0821 L.atm/mol.K × 291.15 K) / 0.9 atm
V ≈ 410.17 L

So, the volume of CO2 generated during the combustion of 500 mL of ethanol is approximately 410.17 liters.

4. Calculate the concentration of CO2:

The concentration of CO2 can be calculated by dividing the moles of CO2 by the volume of the lab environment.

Concentration of CO2 = Moles of CO2 / Volume of lab environment
Concentration of CO2 = 16.94 mol / Volume of lab environment

Since the unit of concentration is mol.L-1, we need to convert the volume of the lab environment to liters. You haven't provided the volume of the lab, so if you provide that value, I can assist you further in calculating the concentration of CO2.