Chlorine gas was first prepared in 1774 by the oxidation of NaCl with MnO₂: 2 NaCl(s) + 2 H₂SO₄(l) + MnO₂(s) → Na₂SO₄(s) + MnSO₄(s) + 2 H₂O(g) + Cl₂(g) Assume that the gas produced is saturated with water vapor at a partial pressure of 28.7 mm Hg and that it has a volume of 0.597 L at 27 °C and 755 mm Hg pressure. (a) What is the mole fraction of Cl₂ in the gas?

Video transcript

Welcome back everyone by oxidizing sodium fluoride with manganese oxide. Flooring gas can be created. Were given the following equation where two moles of sodium fluoride solid react with two moles of sulfuric acid and one mole of manganese oxide solid To produce two moles or sorry, one mole of sodium Sulfate solid, one mole of manganese sulfate solid and two moles of liquid water and one mole of flooring gas. Assume that the produced gas has a volume of .631 leaders at 26°C, a pressure of 700 and 62 millimeters of mercury and is saturated with water vapor at a partial pressure of 27.9 millimeters of mercury. What is the mole fraction of flooring gas in the gas? So what we want to recall is Dalton's law, which we can apply in terms of this described reaction, where our flooring gas is collected through the bubbling of our water vapor. And so we can say that the total pressure is equal to the pressure of our flooring gas added to our pressure of our water vapor. And this should equal 762 mm of mercury according to our prompt. So to solve for our pressure of our flooring gas, we would isolate it and say that that is equal to the difference between our total pressure and our pressure of water. Now, according to the prompt, we are given our pressure of water as 27.9 mm of mercury. So we're just going to plug in our knowns and what we're going to have is that our pressure of our flooring gas is equal to the total pressure given in the prompt as 762 millimeters of mercury subtracted from. And sorry, this should be a subtraction sign here. So this is subtracted from our pressure of our water vapor given as 27.9 millimeters of mercury. So this is going to give us our pressure of our flooring gas equal to a value of 734.1 millimeters of mercury. So now to get our mole fraction of our flooring gas, we're going to recall that we take the pressure of our component. So being our flooring gas divided by the total pressure Plus our pressure of our or rather it would just be our total pressure since it would include everything in our system. And so plugging in what we know we just saw for our pressure of our flooring gas as 734.1 mm of mercury. Just slide this over and this is divided by our total pressure which was given to us in the prompt as 762 mm of Mercury. So what this will simplify too is a value of .963 and this would be our final answer as the mole fraction of flooring gas in our gas produced. So what's highlighted in yellow is our final answer. I hope everything I explained was clear. If you have any questions please leave them down below, and I will see everyone in the next practice video.