Question

The outermost shell of a ______ element has two electrons.
1. Carbon
2. Boron
3. Magnesium
4. Chlorine

Answer 1

Correct Answer - Option 3 : Magnesium

The correct answer is Magnesium.

• The outermost shell of a Magnesium element has two electrons.
  • 12 is the atomic mass for magnesium.
  • it is in group 2 of the periodic table, which it loses, so its outer shell is full (2,8).
  • it has a charge of +2, as it still has 12 protons (positive charges) and now has only 10 electrons (negative charges).
  • Magnesium is used in products that benefit from being lightweight, such as car seats, luggage, laptops, cameras, and power tools.
  • It is also added to molten iron and steel to remove sulfur. 
• Outermost Shell :
  • This outermost shell is known as the valence shell, and the electrons found in it are called valence electrons.
  • In general, atoms are most stable, least reactive, when their outermost electron shell is full.

• Carbon is a chemical element with the symbol C and atomic number 6.
  • It is nonmetallic and tetravalent-making four electrons available to form covalent chemical bonds.
  • It belongs to group 14 of the periodic table. 
  • Carbon typically shares electrons to achieve a complete valence shell, forming bonds with multiple other atoms.
• Boron is a chemical element with the symbol B and atomic number 5.
  • The boron atom has only six electrons in its outer shell, leading to an electron deficiency.
  • This molecule has 12 valence shell electrons, 3 each from the B atoms, and 1 each from the six H atoms.
    • Electrons per shell: 2,3
    • Atomic Mass: 10.811 g/mol
• Chlorine atom consists of 17 protons (positively charged sub-atomic particles) in the atom's nucleus (central region), balanced by seventeen electrons (negatively charged sub-atomic particles) distributed around the nucleus.