Hydrogen sulfide will react with water as shown in the following reactions. H₂S(g) + H₂O(l) H₃O⁺(aq) + HS^-(aq) K₁= 1.0 × 10^-7
HS^-(aq) + H₂O(l) H₃O⁺(aq) + S^2-(aq) K₂= ?
H₂S(g) + 2H₂O(l) 2H₃O⁺(aq) + S^2-(aq) K₃= 1.3 × 10^-20
What is the value of K₂?

Question

Hydrogen sulfide will react with water as shown in the following reactions. H₂S(g) + H₂O(l)

Hydrogen sulfide will react with water as shown in the following reactions. H<sub>2</sub>S(g) + H<sub>2</sub>O(l) H<sub>3</sub>O<sup>+</sup>(aq) + HS<sup>-</sup>(aq) K<sub>1 </sub>= 1.0 × 10<sup>-7</sup> HS<sup>-</sup>(aq) + H<sub>2</sub>O(l) H<sub>3</sub>O<sup>+</sup>(aq) + S<sup>2-</sup>(aq) K<sub>2 </sub>= ? H<sub>2</sub>S(g) + 2H<sub>2</sub>O(l) 2H<sub>3</sub>O<sup>+</sup>(aq) + S<sup>2-</sup>(aq) K<sub>3 </sub>= 1.3 × 10<sup>-20</sup> What is the value of K<sub>2</sub>? A) 1.3 × 10<sup>-27</sup> B) 2.3 × 10<sup>-7</sup> C) 1.3 × 10<sup>-13</sup> D) 7.7 × 10<sup>12</sup> E) 7.7 × 10<sup>26</sup>

H₃O⁺(aq) + HS^-(aq) K₁= 1.0 × 10^-7
HS^-(aq) + H₂O(l)

H₃O⁺(aq) + S^2-(aq) K₂= ?
H₂S(g) + 2H₂O(l)

2H₃O⁺(aq) + S^2-(aq) K₃= 1.3 × 10^-20
What is the value of K₂?

Quizplus · Accepted Answer

The first reaction is the reverse of the second reaction, so their equilibrium constants are inversely related to each other. That means K₃ is the reciprocal of K₂. Using this relationship and the given value of K₃, we can calculate: K₃ × K₂ = 1.3 × 10^-20 K₂ = (1.3 × 10^-20) / K₃ = (1.3 × 10^-20) / (1.0 × 10^-7) = 1.3 × 10^-13. Therefore, the answer is C.

Hydrogen Sulfide Will React with Water as Shown in the Following