Consider the equilibrium system below. Upper N upper H subscript 4 upper H upper S (s) double-headed arrow upper N upper H subscript 4 upper C l (g).

If the system is at dynamic equilibrium, which statement is true?
Sublimation of the NH4CI crystals stops.
Solidification of the NH4CI vapors stops.
The rate of sublimation of the NH4CI crystals is equal to the rate of solidification of the NH4CI vapors.
The rate of sublimation of the NH4CI crystals is higher than the rate of solidification of the NH4CI vapors.

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.  

1.43 x 10^-11 j the guy commented the awnser just making sure u see it .

lol for the pointsss