At 218°C, 𝐾_𝑐 = 1.2×10⁻⁴ for the equilibrium NH₄SH(𝑠) ⇌ NH₃(𝑔) + H₂S(𝑔) Calculate the equilibrium concentrations of NH₃ and H₂S if a sample of solid NH₄SH is placed in a closed vessel at 218°C and decomposes until equilibrium is reached.

Video transcript

Hello everyone. Today we have the following problem. The equilibrium constant for the following decomposition reaction at 212°C is 1.2. What are the equilibrium concentrations of chlorine, chlorine and oxygen gas? If a sample of our calcium hypochlorite is put inside a closed container at two, 12°C and allowed to reach equilibrium. So what we first want to do it's right are equal expression. But we must take into account some things. We're gonna only include Aquarius and gaseous species in this equal expression, solids and liquids are ignored. And another thing we want to focus on is the fact that coefficient, so coefficients are going to be our exponents in the expression. And then we're gonna use brackets to indicate concentration. So writing out our equilibrium expression, equilibrium expression, it's going to be the concentration of our products over our reactant. Since both of our, our reactant are solids, we are not going to include them. So we're just gonna include our products, which is our chlorine gas and our oxygen gas. So based on solid geometry principles, the concentrations of these two are going to be the same. So we're going to let X represent the concentration of our chlorine gas, which is going to be equal to the concentration of oxygen gas. If we let X represent that our expression can be as follows, we will have our K C equal to X times X which is X squared. Furthermore, We know that our KC expression is 1.2 or the equilibrium constant. So we're gonna do 1.2 is equal to X squared. We're gonna take the square root of both sides. And that's gonna give us X equaling 1.1 molar as our final answer. So these are the equilibrium concentrations of both of our products. And with that, we've answered the question overall, I hope this helped. And until next time.