What does all matter have in common? a. all matter is solid b. all matter is to small to see c. all matter is made up of molecule d. all matter is a gas at room temperature

All matter is made up of molecule.

the atomic mass is the bottom number on the element.

-steel jelly

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.

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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.