Which of the following molecules contains polar covalent bonds? O H2
O H20
O NaCl
O CH4

H₂O

Explanation:

Hello,

In this case, polar covalent bonds are identified by looking the electronegativity difference between the bonding atoms, if its less than 1.7 and more than 0.7, thus, for water, H₂O, it turns out:

Thereby, it is polar covalent, whereas the other ones are ionic or nonpolar covalent.

Regards.

adding or remove a gaseous reactant or product changes the concentrations. if the concentration of reactant or product is increased, the system will shift away from the side in which concentration was increased (i.e. if the concentration of reactants is increased, the system will shift toward the products. if more products are added, the system will shift to form more reactants). conversely, if the concentration of reactant or product is decreased, the system will shift toward the side in which concentration was decreased (i.e. if reactants are removed, the system will shift to form more reactants. if the concentration of products is decreased, the equilibrium will shift toward the products).

explanation:

the answer is c i believe