For each of the following gas-phase reactions, indicate

how the rate of disappearance of each reactant is related

to the rate of appearance of each product:

(b) 2 N₂O(g) → 2 N₂(g) + O₂(g)

Video transcript

Welcome back, everyone consider the gas phase reaction given below. In relation to the rates of appearance of the products. What is the rate of disappearance of the reactant for this problem? We simply want to recall how we define the reaction rate in terms of the change in concentration of either a product or a reactant. If we start with our reactant on the left hand side, that would be no three. We first will have to begin with a negative sign because a reactant has a negative change in concentration. Then we are essentially using a fraction of one divided by the coefficient in front of that species. And we have two. So we're going to take negative one half. And then we simply want to define the change in concentration of that reactant divided by the change in time. That's how we define the reaction rate in terms of the disappearance of the reactant. And now we can continue using the same pattern just looking at our products, we have our first product which is N two. So there's no leading coefficient, right, meaning we're not going to include any kind of fraction. We also want to take the positive quantity because it's a product and its rate of appearance is essentially positive. So we are simply left with the change in concentration of NC delta NC divided by the change in time. And now finally, we have one more product that would be oxygen 02. Once again, that's positive because it's a product, our fraction would be one divided by three because the coefficient in the balanced equation is three. And then we're using the change in the concentration of oxygen divided by the change in time. And that would be the expression that we're looking for in this problem. It relates the rates of appearance of the products to the rate of disappearance of the reactant. Thank you for watching.