Question Discussion & Solution

The correct answer is Magnesium.

Key Points

• 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.

Additional Information

• 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.

Hence, he is moving in north direction now.

• Becquerel is the SI unit of radioactivity.
• 1 Becquerel = 1 disintegration/Second
  • Disintegration: As the radioactive elements are unstable they will disintegrate at any moment by emitting alpha or beta particles and form new elements called daughter elements which are completely different in both physical and chemical properties when compared to the elements they came from.
  • The rate of disintegration does not depend upon external factors like temperature, pressure, etc.

Mammalogist is a person who studies about mammals. Similarly,

The correct answer is Silver.

Key Points

• Gold
  • It is one of the softest metals, and this quality makes it easier to design it in various jewelry designs.
  • It is tough making 24 karat gold jewelry. Other metals have to be added to it to increase its durability and strength.
  • If you wish to know what is 24 karat gold, you must understand that 24 karat gold is the purest form of this yellow metal.
  • Although 24 karat is pure gold, a jewelry piece made up of this purity is not solid and flexible enough.
  • When creating and crafting beautiful, intricately designed, and patterned gold jewelry, the metal needs to be added with other alloys to lend it the necessary strength.
  • The metals usually added to gold metal are zinc, nickel, silver, copper, etc. Hence, Option 3 is correct.
  • This is because when gold melts its state will change into a liquid.
  • Gold will like water so it flows and it will become difficult to mold.
  • So copper is added to gold which is there in the liquid state, so it will harden gold a little bit to prevent it from flowing which will be easy to mold gold to make ornaments.

Important Points

• Silver
  • It is a chemical element with the symbol Ag and atomic number 47.
  • A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.

Additional Information

• Zinc
  • It is a chemical element with the symbol Zn and atomic number 30.
  • Zinc is a slightly brittle metal at room temperature and has a silvery-greyish appearance when oxidation is removed.
  • It is the first element in group 12 of the periodic table.
• Lead
  • It is a chemical element with the symbol Pb and atomic number 82.
  • It is a heavy metal that is denser than most common materials.
  • Lead is soft and malleable, and also has a relatively low melting point.
  • When freshly cut, lead is silvery with a hint of blue; it tarnishes to a dull gray color when exposed to air.
• Tin
  • It is a chemical element with the symbol Sn and the atomic number 50.
  • Tin is a silvery metal that characteristically has a faint yellow hue.
  • Tin is soft enough to be cut with little force.