What is the mass of an atom with seven protons. seven neutrons, and eight electrons?

Explanation:

It is given that the atom has 7 protons this means that atomic number of the atom is 7.

As we know that atomic mass of an atom is the sum of total number of protons and neutrons present in the atom.

So,       atomic mass of the given atom = no. of protons + no. of neutrons

                                                                = 7 + 7

                                                                 = 14

Thus, we can conclude that the mass of given atom is 14 g/mol.  

d) physical means can be used to separate the components of air.