Answer : The value of equilibrium constant (K) is, 0.004
Explanation :
First we have to calculate the concentration of 

and,

Now we have to calculate the value of equilibrium constant (K).
The given chemical reaction is:

Initial conc. 1.2 0 0
At eqm. (1.2-2x) 2x x
As we are given:
Concentration of
at equilibrium = x = 0.1 M
The expression for equilibrium constant is:
![K_c=\frac{[SO_2]^2[O_2]}{[SO_3]^2}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B%5BSO_2%5D%5E2%5BO_2%5D%7D%7B%5BSO_3%5D%5E2%7D)
Now put all the given values in this expression, we get:



Thus, the value of equilibrium constant (K) is, 0.004
The mass of HCl that is contained in the solution is 147 g HCl
Why?
To find the mass of HCl we have to apply what is called a conversion factor. In a conversion factor we put the units we don't want at the bottom, and the ones we want at the top.
For this question, we want to go from liters of solution to mass of HCl, and the conversion factor is laid out as follows:

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#LearnwithBrainly
They are kind of opposite processes. Chemical synthesis is execution of chemical reactions to make products. Like you take two substances, you put them together, they react and you have new a substance. For example.

here Sodium and Chlorine react to make a new substance which is Sodium Chloride.
Chemical decomposition is process of seperating a substance to different substances. There is a substance by a reaction this substance becomes two substances, Like : XY -> X+Y For example :
Explanation:
precipitation like snow rain with increased acid is know as acid precipitation