The equilibrium constant, Kc, for the reaction H2 (g) + 2 (g) 2H (g) is 54 at 425 ºC. If the equilibrium mixture contains 0.030 M H and 0.015 M 2 , the equilibrium concentration of H2 is.

[H₂] = 0.0011M

Explanation:

Based on the chemical equation:

H₂(g) + I₂(g) ⇄ 2HI(g)

And Kc is defined as:

Kc = [HI]² / [H₂] [I₂]

Where Kc = 54

And [] represents equilibrium concentration of each compund.

Replacing:

54 = [0.030M]² / [H₂] [0.015]

[H₂] = [0.030M]² / 54* [0.015]

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.

indium, and thallium have three electrons i think