Predict whether aqueous solutions of the following compounds are acidic, basic, or neutral: (c) Na2CO3

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Hi everyone for this problem. It reads if potassium sulfate is dissolved in water, will its acquis solution be acidic, basic or neutral. Okay, so in order for us to solve this problem, the first thing that we're going to need to do is disassociate potassium sulfate into its ions. So let's go ahead and get started. When we dissociate potassium sulfate into its ions, we get the following cat ion and an ion. So we have a potassium cat ion and sulfate and ion. So now that we've dissociated this into its ions, we're going to determine the acid and base from which the cat ion and an ion derived from and we can do that for the cat ion by adding hydroxide and for the an ion by adding a proton. Okay, so from there we see that our cat ion is derived from the following base. Okay, potassium hydroxide and potassium hydroxide is a strong base. Okay, we need to recall our rules for strong acids and strong bases. So potassium hydroxide is a strong base and our acid or are an ion when we add a proton comes from the following acid. Okay. And this acid is sulfuric acid. And if we recall sulfuric acid is on our list of strong acids. So now that we know the acid and base from which the cat eye on and and I and derived from we're going to determine if this acid and base is strong or weak. Okay, and so for strong acids and strong bases they have a neutral conjugate base. So let's go ahead and write that here. Okay, a strong acid slash strong base has a neutral conjugate base and a weak acid slash week base has a strong conjugate. Okay, so up here this C B. Should be conjugate. I wrote conjugate base, but so that it relates to both will just write conjugate. Okay, so strong acids and strong bases have a neutral conjugate and weak acids and weak bases have a strong conjugate. Okay, they have an inverse relationship when it comes to a weak acid or a strong acid has a weak conjugate. There have it's an inverse relationship. Okay, so moving forward, so now that we see let's do our potassium hydroxide. This comes from a strong base. Okay, so that means we have a weak conjugate, which means the solution is going to be neutral. And for our strong acid, this is also a weak conjugate, which means it is neutral. All right. So like we said, the stronger the acid or base, the weaker its conjugate. So because we have a neutral for both, our solution overall is going to be neutral. Okay, so that is it for this problem. And that's the answer to this problem. I hope this was helpful

Predict whether aqueous solutions of the following compounds are acidic, basic, or neutral: (c) Na2CO3

Verified Solution

Key Concepts

Acid-Base Theory

Salt Hydrolysis

pH Scale