1. the element symbol for the element with 17 protons is
2. the element with the symbol has an atomic number of 12.
3. the mass number for an element with 17 protons and 18 electrons is
4. the element with an atomic number of 12 and a mass number of 25 has neutrons.
5. a neutral atom with 5 electrons has as an element symbol.
6. an element with 17 protons has an atomic number of .
7. the element with 17 protons and 18 electrons has a charge of .
8. an element with an atomic number of 12 has protons.
9. the element with an atomic number of 12 and a charge of +2 has electrons.
10. a neutral atom with 5 electrons has protons.

The answer is below

Explanation:

1. The element symbol for the element with 17 protons is Cl (chlorine)

2. The element with the symbol _Mg__ has an atomic number of 12.

3. The mass number for an element with 17 protons and 18 electrons is _Cl⁻___.

4. The element with an atomic number of 12 and a mass number of 25 has _13__ neutrons.

5. A neutral atom with 5 electrons has _B__ as an element symbol.

6. An element with 17 protons has an atomic number of _Cl___ .

7. The element with 17 protons and 18 electrons has a charge of _-1___ .

8. An element with an atomic number of 12 has _12___ protons.

9. The element with an atomic number of 12 and a charge of +2 has _10__ electrons.

10. A neutral atom with 5 electrons has _5___ protons.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

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