The general rule followed is that if electronegativity difference is greater than 2, then it is considered an ionic bond. An ionic bond is a type of bond characterizing a transfer of electrons within a bond. Common examples are salts which adds that ionic bonds are common between a metal and a nonmetal. Therefore, the best answer from above is letter B.
I choose the option A.
The electron absorbs energy from specific wavelength then moving from a lower energy orbital to a higher energy orbital.
The correct answer is (D)
All the above are reasons the carbon , oxygen, and nitrogen cycles are vital to life on earth.
The explanation:
because :
1) Carbon, oxygen, and nitrogen are vital components of life on Earth.
2) The carbon, oxygen, and nitrogen cycles allow vital elements to return to usable form by organisms.
3)The carbon, oxygen, and nitrogen cycles are an important interface between biotic and abiotic factors
4) They are all biogeochemical cycles.
5) They all involve an interaction between living and nonliving elements.
6)They are all part of the Earth system.
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles