## A) precipitation reaction.B) oxidation-reduction.C) precipitation reaction.D) acid-base reaction.E) oxidation-reduction.F) acid-base reaction.G) acid-base reactionH) oxidation-reduction.I) precipitation reaction.

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Okay, So this question is, um, problem 32 in the world of chemistry, textbook of the end of chapter eight and this is part of section three. But the question gives us a bunch of unbalanced chemical reactions, and it wants us to determine whether it's a precipitation an acid base. Aren't oxidation reduction reaction. OK, so how do we identify these types of reactions Will for precipitation. If we have a precipitation, you're going to see that you're gonna have to a quiz solutions and they're going to react to become some type of souls. You're going to see a solid form. Okay, so that's what precipitation means. We're gonna have liquids mixed together, and a solid is going to come out of that reaction. Right? For an acid based reaction, you're going to see a transfer of hydrogen ions, h plus ions, and that is going to produce reduce water. Okay, you're going to see a production of water. So if you see water on the product side than it is probably an acid base reactions. And finally, for an oxidation reduction, remember, oil rig right? Oxidation is the loss of electrons and reduction is the gaining of electrons. So this is a reaction where something is losing a life, Franz, and something else is gaining. So you'll see that one of the reactions will lose electrons and another will gain so we can see that there's a transfer of electrons. And remember that electrons air negatively charged. Okay, so for a our first problem, we have potassium sulphate with barium nitrate to create very on a sulfate, which was a solid and potassium nitrate. Okay. And so what I immediately see is that we're forming a solid from two egg Leah Solutions. Okay, so I can immediately say that a A is a precipitation. So we have a percent annotation here. Okay, For B, we have hydrogen chloride or hydrochloric acid, and that reacts with solid sink to make hydrogen gas and zinc chloride. And and so we know that this is not a precipitation because there are no solids being formed. And it's not an acid base because I don't see water being made either. So this must be an oxidation reduction. And one way we can shack is to see if there is a transfer of electrons. We can trace the transfer of electrons And so I would individually look at each, um, Adam and see where I could find the electrons being moved. So the hydrogen chloride I know is an ionic bond. Okay? And I know that chloride is very electoral negative, and it likes to be a negative one charge, which means that the hydrogen must be a plus. One charge zinc isn't elemental form. It's just solid sink, which is a metal. So anything that isn't its elemental form is always neutral. No charge. So zero okay. And same for hydrogen. It's in it's elemental form, so that's zero. And then zinc bonded to chloride, two of them chloride. Each of them will be negatives to remember each. There's two negatives. So that means that the zinc must be a two plus all right. And so if you look this, we have ah hydrogen of the plus that becomes neutral or no charge. So it must have gained electrons, whereas the zinc went from a zero plus, which means that it must have lost electrons. Remember? Electrons are negatively charged to We're losing a negative charge. All right, so we know that this is an oxidation reduction. All right? For C. We have hydrogen chloride or hydrochloric acid, um, reacting with silver nitrate to make nitric acid and silver chloride. Okay. So immediately, I see that we were We are making a solid again. Okay. From to agree a solutions. He said to a quiz solutions become a solid. So we know that this is a precipitation. Okay, for D. We are going from hydrochloric acid with potassium hydroxide to make water. Okay. And cool. Ride salt. Okay, so we're making water, so I immediately think Okay, this is probably going to be an acid base. Let's confirm by seeing if there's a transfer of H plus, they transfer of hydrants. And I do see that this hided in from hydrochloric acid, uh, reacts with the ole each from the past, um, hydroxide okay to form water. And then the cool ride and the potassium combined to make the potassium chloride salt pay. So we know that this is acid base. All right. For E, we have zinc solid zinc and copper sulfate coming together on to form zinc sulfate and coppers. Solid copper. Okay, so we are not making water, so this is not an asset base, and we aren't forming a solid. So it does seem like this might be a precipitation because we have a solid in the product side. But we also have a solid and the reaction side, remember, a precipitation is when we have to Equus solutions becoming a solid. Okay, so this is not considered a precipitation. This must be an oxidation reduction maintain. And so we can track by tracing the movements of electrons. All right, so sink, it's elemental form of zero and copper sulfate. So I know that sulphate is two minus, which means that the copper must be two plus and same here. The sulfite is two minus. So this time the sink is two plus, and our copper is now neutral. Okay, So what's happening is that the sink, which was neutral, um, goes to a two plus state, which means that it lost electrons and the copper goes from a two plus two, a neutral state where no charge state, which means that it's and electrons. Okay, so we know that e must be another oxidation reduction reaction, and we have four more in this problem. Okay, so four s, we have sodium mono sodium phosphates in the Equus solution with sodium hydroxide to form sodium phosphate and water. Okay, so immediately, I see that were forming water. And so I am thinking that this is gonna be an asset base reaction. So I just want to confirm it by seeing if I I find a transfer of hydrogen. Hey, and I do see that with this these hydrogen is here. React with the O age group here to form our water. Okay. And what's left is our sodium and our phosphate to make sodium phosphate. Okay, so I know now that af is an acid base. Reaction are right for G again, we have calcium hydroxide whistle for uric acid to make calcium sulfate, and I see we're making water again. OK, so I am thinking this is gonna be acid base. So let's check if there is a transfer of hydrogen is and I do see that these hydrogen is react with this o age group to form water. Okay. And the rest create this calcium sulfate. Okay, so this again is an acid ace reaction for H. We have zika chloride, which is a quiz with magnesium, which is a solid, and this forms zinc solid and magnesium chloride, which is a quickest again even though we're forming a solid since we're coming from a solid, this is not considered a precipitation. Remember, we need to Equus solutions to come together form a solid for it to be considered a precipitation. Okay, we're also not making water, so I know that this is not an asset base. This is probably going to be an oxidation. Let's check by tracing the movements of electrons. So again, chloride, we know is negative and there are two of them, which means that this is too close and this magnetism is elemental. So that's, uh, neutral and the zinc as well came no charges on both of them and then magnesium chloride. Okay, the chloride again is negative and there are two of them. So this magnesium must be two plus. Okay, so we know that this must be an oxidation reduction because we see a transfer of electrons. We go from zinc two plus to zinc that is neutral and magnesium, which is neutral and then goes to a two plus state. So we know that this is another oxidation or reduction. Okay. And finally, we have I, Which is barium chloride in the atria solution with sulfuric acid, which is a quiz to make barium sulfate, which is a solid and hydrochloric acid. Okay, so we are forming a solid, and we're coming from to a glia solutions, Okay. And so we do know that this is a precipitation. There are no hydrogen is being transferred. Nor are there, um, electrons being moved. Okay. And there is no water being made. Remember for a acid base, there needs to be water being produced. I mean, we don't see that either, so we know that this is just a precipitate, all right? And so that is how you solve questions. Pretty too. From the world of chemistry. Thank

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