High School

What moles of chlorine gas, [tex]Cl_2[/tex], are contained in a 10.0 L tank at 27°C and 3.50 atm of pressure?

A. 1.42 grams
B. 142 grams
C. 1.01 kg
D. 101 grams

Answer :

The moles of chlorine gas in a 10.0 L tank at 27°C and 3.50 atm is approximately 1.42 moles, which corresponds to about 101 grams of Cl2.

To calculate the moles of chlorine gas (Cl2) in a 10.0 L tank at 27°C and 3.50 atm, we use the ideal gas law PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant (0.0821 L*atm/K*mol), and T is the temperature in Kelvin.

First, we convert the temperature to Kelvin (K):

T(27°C) = 27 + 273.15

= 300.15 K.

Now, we can solve for n:

n = (PV) / (RT)

= (3.50 atm * 10.0 L) / (0.0821 L*atm/K*mol * 300.15 K)

n ≈ 1.42 moles

Using the molar mass of chlorine (70.90 g/mol), we convert moles to grams:

Mass = moles * molar mass

= 1.42 moles * 70.90 g/mol

= 100.68 grams, which is closest to the answer choice (d) 101 grams.