Pretty sure it’s sodium oxide.. ?
The density of the sample is 0.96 g/mL.
Density is found by dividing the mass of an object by its volume.
D=m÷v
D=35.4 g÷36.82 mL
D=0.96 g/mL
Atomic weight of an element can be calculated as follows:
average atomic weight =
(atomic weight of first isotope)(its percentage of abundance) +
(atomic weight of second isotope)(its percentage of abundance)
average atomic weight = 98.225 amu
atomic weight of first isotope = 97.780 amu
its percentage of abundance = 1 - 0.417 = 0.583
atomic weight of second isotope = ??
its percentage of abundance = 0.417
So, just substitute in the above equation to get the atomic weight of the second isotope as follows:
98.225 = (97.78)(0.583) + (mass2)(0.417)
atomic weight of second isotope = 98.847 amu
