Answer:A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.
Explanation:
Answer : The energy of one photon of hydrogen atom is, 
Explanation :
First we have to calculate the wavelength of hydrogen atom.
Using Rydberg's Equation:

Where,
= Wavelength of radiation
= Rydberg's Constant = 10973731.6 m⁻¹
= Higher energy level = 3
= Lower energy level = 2
Putting the values, in above equation, we get:


Now we have to calculate the energy.

where,
h = Planck's constant = 
c = speed of light = 
= wavelength = 
Putting the values, in this formula, we get:


Therefore, the energy of one photon of hydrogen atom is, 
The answer to the question is A
Answer:Poopy-di scoop
Scoop-diddy-whoop
Whoop-di-scoop-di-poop
Poop-di-scoopty
Scoopty-whoop
Whoopity-scoop, whoop-poop
Poop-diddy, whoop-scoop
Poop, poop
Scoop-diddy-whoop
Whoop-diddy-scoop
Whoop-diddy-scoop, poop
Explanation:
They have pure elements or a verity of compounds inside.