To identify a diatomic gas (x2), a researcher carried out the following experiment: she weighed an empty 5.8-l bulb, then filled it with the gas at 1.00 atm and 21.0 ∘c and weighed it again. the difference in mass was 6.7 g. identify the gas. express your answer as a chemical formula.

Explanation:

The given data is as follows.

      Volume = 5.8 L,    Pressure = 1.00 atm

      T = = (21 + 273) K = 294 K,   mass = 6.7 g

     R = 0.0821 Latm/mol K

According to the ideal gas equation, we will calculate the number of moles as follows.

             PV = nRT

or,          n =

Hence, putting the given values into the above formula as follows.

               n =

                  =

                  = 0.24 mol

Now, calculate molar mass of the gas as follows.

            Molar mass =

                                =

                                = 27.91 g/mol

or,                             = 28 g/mol (approx)

As the gas is diatomic so, mass of two atoms of gas X is 28 g/mol. And, mass of one atom of gas is as follows.

                          = 14 g/mol

Hence, nitrogen atom has a mass of 14 g/mol. Therefore, we can conclude that the given diatomic gas is .