Hydrogen and chlorine react to form hydrogen chloride, like this: H2(g) + Cl,(g) → 2 HCl(g)
Also, a chemist finds that at a certain temperature the equilibrium mixture of hydrogen, chlorine, and hydrogen chloride has the following composition:
compound pressure at equilibrium
H2 0.78
Cl2 1.2M
HCl 1.6M
Calculate the value of the equilibrium constant for this reaction. Round your answer to significant digits.

The value of the equilibrium constant for this reaction is 2.7

Explanation:

Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as  

For the given chemical reaction:

The expression for is written as:

Thus the value of the equilibrium constant for this reaction is 2.7

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.