A 0.115 mol sample of Xe gas is contained in a 4.00 L flask at room temperature and pressure. What is the density of the gas, in grams/liter, under these conditions?

density = 3.77 g/L

Explanation:

The density of the gas is the mass of the gas divided into the volume:

density = mass/volume

We can obtain the mass from the moles of gas and the molar mass. From the Periodic Table, we know that the molar mass of Xe is 131.3 g/mol. Thus, we multiply the number of moles by the molar mass (MM):

mass = moles x MM = 0.115 mol x 131.3 g/mol = 15.09 g

Finally, we calculate the density by dividing the mass into the given volume:

density = mass/volume = 15.09 g/4.00 L = 3.77 g/L

"the periodic table is arranged in order of atomic number."

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.