How is the mass defect determined? A. The mass defect is determined by measuring the mass of emitted
alpha particles
B. The loss of mass of a nucleus is determined by looking at its line
spectrum
C. The parent nuclear mass is divided by the daughter nuclear mass.
D. The mass of a nucleus is subtracted from the mass of its
components.

whats the meaning of /

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

pv=nrt

explanation: