The mass of an atom is

a. distributed uniformly throughout the atomic sphere.
b. concentrated in the electrons
c. divided equally between the nucleus and the electrons.
d. concentrated in the nucleus.

Chur answerwould be B concentrated in the nucleus

A. distributed uniformly throughout the atomic sphere

I think it might be right

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.