What can we learn by the number of electrons on the outer energy level of an atom? (2 points) Physical properties such as color and texture Physical properties such as mass and density Chemical properties such as its ability to form chemical bonds Chemical properties such as boiling point and melting point.

Chemical properties such as its ability to form chemical bonds

Explanation:

The group to which an element belong is known by the number of electrons on its outermost shell. Since chemical reactions often involve valence electrons of an atom, the number of outermost shell electrons give us an idea of the chemical properties, reactivity and readiness of the element to form chemical bonds. The number of electrons in the outermost shell is the most succinct description of the chemical disposition of any atom.

your mom.com . : 0000

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.