8. Hydrogen and iodine gas placed in a sealed container at 490°C will form hydrogen iodide. The equilibrium constant for this equilibrium mixture is 46.0. If initially 0.40 mol
of hydrogen and 0.6 mol of iodine are injected into a 500. mL electrically heated
reaction vessel, what are the concentrations of all the entities at equilibrium?

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.  

explanation:

0.07 g/cm³

1.37 g/cm³