Which phrase describes valence electrons? (1 point) O electrons that are shared between atoms
the electrons surrounding an atali's nucleus
the electrons in an atom's outermost energy level
electrons that are exchanged between atoms

C

Explanation:

the electrons in an atom's outermost energy level

well in order to answer this question you have to provide more information < 3

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.