A covalent bond is formed when: a. two nonpolar molecules associate with each other in a polar environment. b. a positively char
ged particle is attracted to a negatively charged particle. c. one atom gives up electrons to another atom. d. two atoms share electrons. e. two polar molecules associate with each other in a nonpolar environment.
Chemical bonds are very important in chemical reactions. Examples of chemical bonds include electrovalent, covalent etc.
Covalent bonds deals with sharing of electron by two atoms. A common example is that of H2O( Water) in which the Hydrogen atoms share their electrons with the oxygen and the oxygen also shares its own electrons with the hydrogen in a mutual manner.
A covalent bond is formed when atoms share electrons. These can be seen in diatomic molecules such as oxygen (O2), hydrogen (H2) , Chlorine (Cl2) molecule and also in Methane (CH4), Water ( H2O) e.t.c.
In facilitated diffusion, molecules diffuse across the plasma membrane with assistance from membrane proteins, such as channels and carriers. A concentration gradient exists for these molecules, so they have the potential to diffuse into (or out of) the cell by moving down it.