An atom has 9 electrons and 9 protons at the start. if it loses 2 electrons, the net charge on the atom will be . if the atom instead gains 4 electrons, the net charge will be

If the atom loses 2 electrons, the net charge on the atom will be 2+

If the atom gains 4 electrons, the net charge on the atom will be 4-

Explanation:

An atom is smallest unit of a matter or substance.It consist of three subatomic particles : electrons, protons, neutrons.

Protons are positively charged, neutrons are neutral and both are located in nucleus where mass of an atom is concentrated.

Electrons are negatively charged and are located outside the nucleus where they orbit in different energy levels around the nucleus.

In an atom, when electrons are lost, the atom gains a positive charge and forms cation. In an atom, when electrons are gained, the atom occupies a negative charge and forms anion.

Thus an atom with 9 electrons and 9 protons will be electrically neutral.

On losing 2 electrons, there will be 7 electrons and 9 protons will have 2+ charge.On gaining 4 electrons, there will be 13 electrons and 9 protons will have 4- charge.

c (diamond),

sio2 (quartz)

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.