The question is incomplete, the complete question is:
Consider the reaction:

At equilibrium, the concentrations are as follows. [NOCl] = 1.4 × 10–2 M [NO] = 1.2 × 10–3 M [Cl2] = 2.2 × 10–3 M What is the value of Keq for the reaction expressed in scientific notation?
A) 1.6 × 10–5
B) 6.2 × 10–4
C) 6.2 × 10+4
D) 1.6 × 10+5
<u>Answer:</u> The correct option is A) 
<u>Explanation:</u>
The equilibrium constant is defined as the ratio of the concentration of products to the concentration of reactants raised to the power of the stoichiometric coefficient of each. It is represented by the term 
For the given chemical equation:

The expression for equilibrium constant will be:
![K_{eq}=\frac{[NO]^2}{[Cl_2][NOCl]^2}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BNO%5D%5E2%7D%7B%5BCl_2%5D%5BNOCl%5D%5E2%7D)
Given values:
![[NO]=1.2\times 10^{-3}M](https://tex.z-dn.net/?f=%5BNO%5D%3D1.2%5Ctimes%2010%5E%7B-3%7DM)
![[Cl_2]=2.2\times 10^{-3}M](https://tex.z-dn.net/?f=%5BCl_2%5D%3D2.2%5Ctimes%2010%5E%7B-3%7DM)
![[NOCl]=1.4\times 10^{-2}M](https://tex.z-dn.net/?f=%5BNOCl%5D%3D1.4%5Ctimes%2010%5E%7B-2%7DM)
Putting values in above expression, we get:

Hence, the correct option is A) 