The mixing of which pair of reactants will result in a precipitat...

Question

The mixing of which pair of reactants will result in a precipitation reaction?

Accepted Answer

hey everyone in this example, we need to identify a pair of compounds that would form a precipitate when reacted together. We want to recall that a precipitate as a solid product. And looking at our first answer choice, we have lithium kreuger and ammonium sulfide. Recall the ions present in these compounds. So we would have L I plus one per Cloyd is cielo four minus, Ammonium is NH four plus and sulfide we recall is S 2 -. Now we're going to recall that this is a double replacement in order to predict our products. So we're pairing up the opposite lee charged ions. So we would pair those two as well as these two ions here. So writing out our first product, we would form ammonium chlorine. So NH four cl 04 when we crossed the charges. And recall that most close rates are soluble. So in this case this would have the accu label because it's soluble. Now. Our second product is going to be lithium sulfide. So when we cross the charges, that would be a lie to us and we want to recall that sulfides are generally insoluble. With the exception of an atom like lithium where lithium is actually going to hide relies. So a K A. It's going to break down in a second reaction where it breaks down into hydroxide, an ion as well as hydrogen sulfide gas. And so this is going to be a gas and then this is going to be a quiz because it's an an ion. And so essentially this would not be one of our final products but everything else would be our final products in the reaction. So we would have this and these as our final products from the first answer choice. So in this case everything is Aquarius and then we have a gas which is not a solid. And so we would rule out answer choice A. Because we did not form a precipitate. Moving on to answer choice B. We have potassium iodide and lead to nitrate. So writing out the ions present, we have the K plus kati on, we have the I minus an ion. We have the PB two plus cat eye on. And then we have the nitrate, no 31 minus an ion. So again we pair up our opposite lee charged ions to form our products. So these two and then these two. So our first product that we would form would be led I died. So that would be P. B. I. To when we crossed the charges and we want to recall that I died are generally soluble. With the exception of when I responded to an atom like PB two plus which it is in this case. And so therefore this would actually be a solid precipitate as a product because it's insoluble. So it does not get the label. So our second product that we would form would be potassium nitrates. Okay, and '03 when we cross the charges. And we want to recall that nitrates are always soluble. So this gets the AQ label because it's soluble. And so this would definitely be a correct answer choice because we did form a solid precipitate as a product being our lead. I died. So moving on to our second or sorry, our third answer choice. We have sodium nitrate and then lead acetate or lead to acetate. So we're going to ride out the ions yet again. So we would have the N. A. Plus cat eye on the nitrate and I on the lead two plus cat ion. And then the acetate ion we recall is CH three C. +021 minus. So yet again we pair up our opposite lee charged ions in a double replacement. And so what we're going to form for our first product, we have sodium acetate. So N A C H three C 02. And recall that acetate are always soluble. So this gets the label. And then for our second product we would form lead nitrate. So we would have PB and then N. 03 and then two when we cross the charge. And we want to recall a yet again that according to our sustainability rules, nitrates are always soluble. So this also gets the AQ label and we rule out into choice C. Because it is not for many precipitates as products. So lastly we have answer choice G. D. Where we have nickel to nitrate and calcium chloride. So writing out the ions present in these compounds, we have an I. Two plus N. 031 minus C A two plus. And then recall chloride is cl one minus. So yet again we pair up the opposite we charged ions and a double replacement. And so we would form the following products where we have calcium nitrate. So C. A N. 03 to when we cross the charges again, nitrates according to our scalability rules are always soluble. So they get the AQ label and then our second product is going to be nickel chloride. So N. I. C. L two. Where we want to recall that chlorides are generally going to be soluble. With the exception of certain atoms. Which nickel is not one of those exceptions. And so therefore this definitely keeps its acquis soluble soluble label. And so we can rule out answer choice D. Because we did not for many precipitates. So this confirms that answer choice B is our only correct choice. It was the only reaction that produced a solid precipitate being our lead. I died from the two reactant, potassium I died and lead to nitrate. So if you have any questions, please leave them down below. Otherwise, I will see everyone in the next practice video

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The mixing of which pair of reactants will result in a precipitation reaction?

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