which of the following would cause the rate of a chemical reaction to slow? All right, a increase in temperature of the reactant. Remember, the rule of thumb is if you're increasing the temperature of the reactant, that's always going to cause an increase in your rate, because the molecules will absorb this thermal energy and use it to energize themselves to move faster, hitting each other more often and, with greater force, be increasing concentration of the reactant well. If you're increasing the concentration of reactant, there's more reactions floating around, so they're more likely to hit each other, which increases their chances of successfully colliding together. So this would only increase your rate, not decrease it. See increased surface area of the reactant. Increasing the surface of your area of your reactions always causes an increase in your rate, because there's just more spots where things can connect together. So here this always makes the rate faster. The answer here is increase in volume that the reactions take up. This is the answer. If we think about it, let's say we have a container that's this big, and in it we have some floating molecules. They have to collide in order to successfully combine. But what would happen if I increase the volume of the container? Yeah, while keeping the number of molecules the same, right? No, I'm not. I didn't actually count each dot from the first container, but just think of this visualization. Here. The container is bigger. Are the reactive molecules more likely or less likely to collide together? Now they're less likely because there's so much more space between them. There's a lower chance of them finding each other colliding. And then, hopefully some of those collisions lead to sticking together because, remember, you can collide with each other. That doesn't guarantee you'll stick together. Alright, so here, increasing the volume that the reactions increasing volume that the reactions take up means the increase in the container volume. This does not help reaction rate. It lowers it because reactive molecules are less likely to find each other right. So here only option D would potentially slow down a chemical reaction