So the first one is yellow and the other one is white
Answer:
a. 
b. K = 192.9
c. Products are favored.
Explanation:
Hello!
a. In this case, according to the unbalanced chemical reaction we need to balance HCl as shown below:

In order to reach 2 hydrogen and chlorine atoms at both sides.
b. Here, given the concentrations at equilibrium and the following equilibrium expression, we have:
![K=\frac{[HCl]^2}{[H_2][Cl_2]}](https://tex.z-dn.net/?f=K%3D%5Cfrac%7B%5BHCl%5D%5E2%7D%7B%5BH_2%5D%5BCl_2%5D%7D)
Therefore, we plug in the data to obtain:

c. Finally, we infer that since K>>1 the forward reaction towards products is favored.
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C. Include changes that alter the identity of a substance.
Answer:
-105 kJ
Explanation:
The enthalpy change of a reaction is the sum of the energy of the bonds of the reactants and the products. The bonds at the reactants are being broken, so it's an endothermic reaction, so the bond energy must be positive.
The bonds at the products are being formed, so the process is exothermic, and the bond energy must be negative. There are being broken 1 N≡N bond and 3 H-H bonds, and are being formed 6 N-H bonds:
Reactants: 945 + 3*432 = 2241 kJ
Products: 6*(-391) = -2346 kJ
ΔH = 2241 - 2346
ΔH = -105 kJ