REVISING HABER PROCESS AND LABORATORY PREPARATION OF AMMONIA. GCE 2018 SCIENCE P2

[00:00:00]Hello everyone. Welcome back to the channel again. So, now let's dive in in preparation of ammonia.

[00:00:08]So, we are going to summarize how to prepare ammonia both in the laboratory and also in industries.

[00:00:17]So, in a laboratory, this is the question. Okay?

[00:00:21]This is the question because it is saying the diagram below illustrates the laboratory preparation of ammonia. So, this is 2018.

[00:00:29]But, I'll also show you the Haber process because the Haber process is very cardinal on section C. Yeah, section C. Haber process, you need to know that. All right. So, let's start with the lab the laboratory preparation. It is saying the diagram below illustrates illustrates the laboratory preparation of ammonia.

[00:00:52]So, we have this diagram here.

[00:00:55]If you can see, we have heat being applied here.

[00:00:58]Inside here, we have ammonium chloride and calcium hydroxide.

[00:01:03]So, we this this mixture is being heated here.

[00:01:08]Then, we have condensed steam here.

[00:01:11]Okay?

[00:01:12]Then here, we have X substance X. Then, we have ammonia being collected here.

[00:01:18]The first question is saying, "Construct a balanced chemical equation for the reaction being illustrated in the diagram above. Preparation of ammonia using ammonium chloride and calcium what? Hydroxide."

[00:01:35]So, this is very important and very cardinal.

[00:01:41]So, let's write this equation.

[00:01:45]So, the equation in this case, we have two things. We have our ammon- we have ammonium chloride reacting with calcium what? Hydroxide here. So, what are we going to say? We will take first ammonium chloride and calcium hydroxide because these two are reacting. So, ammonium chloride is this.

[00:02:11]This is ammonium chloride. It is reacting with what?

[00:02:15]With calcium calcium hydroxide. So, calcium hydroxide this calcium hydroxide. Okay.

[00:02:24]Then this is producing now what? It is producing ammonia. But, what what other products are being produced? So, this this equation usually comes and you need to know it. When ammonium chloride reacts with calcium hydroxide it gives out calcium chloride water and ammonia. Three things they might ask you. So, the first thing is calcium chloride.

[00:02:53]Then, we also have H2O, water. Plus, the last thing which is now our main product, ammonium I mean ammonium.

[00:03:05]Yeah, so this is the equation. Okay?

[00:03:08]This is very important, but of course it's not balanced. So, we need to balance it up because that's that's what the question is saying, construct a balanced chemical equation. So, ammonium chloride reacting with these two form this salt, water, and nitrogen. I mean, ammonia.

[00:03:25]So, how do we balance it now?

[00:03:28]You start from here. How many nitrogens do we have?

[00:03:34]One.

[00:03:36]Okay? One on the left side. What about on the right side? Only one. Okay. What about hydrogens? Four.

[00:03:43]Plus So, when you see in brackets, this two affects everything. So, this two is with everything. So, hydrogen is two here plus this four, six. What about here? We have two this three.

[00:03:57]So, this is five. So, hydrogen is not what? Is not balanced.

[00:04:01]Okay?

[00:04:02]So, it is not balanced. What can we do here?

[00:04:06]If we add a two here, it means these hydrogens now become three multiplied by two, six, plus this, eight. And here we only have what? We have two.

[00:04:19]Plus this, which is four.

[00:04:24]Okay? So, if we add a two here, these hydrogens become four here.

[00:04:30]I mean, four multiplied by two, eight.

[00:04:33]Eight plus these two, we have in total 10 on the left side. And here we have three multiplied by two, six.

[00:04:42]So, if we add a two here also, this becomes four.

[00:04:47]Okay? So, four plus this six, even this side we have 10 hydrogens. Okay? So, the hydrogens are what? Are balanced up. Then, let's look go for chlorine. Chlorine is two here. What about here? It is two. So, it's balanced. Then, let's go for calcium.

[00:05:06]It is one, even here one.

[00:05:09]Oxygen here is two outside here. What about here?

[00:05:15]This two affects everything. So, even here we have two. So, this is balanced.

[00:05:20]So, this is the equation they needed you to write.

[00:05:23]Very important. So, this equation doesn't change. You need to know this.

[00:05:27]You need to master it for the laboratory preparation of ammonia.

[00:05:32]Then, the second equation. So, this was our A.

[00:05:36]We go to B.

[00:05:38]State the common name of substance X.

[00:05:41]This substance X is always quicklime.

[00:05:45]It doesn't change. You need to know that. Okay? It is always what?

[00:05:50]Quicklime.

[00:05:51]We always use quicklime here.

[00:05:53]So, for our B1, it is quicklime.

[00:06:02]So, we we have quicklime, we have slaked lime, but in this case we use quicklime.

[00:06:09]Okay?

[00:06:11]Then, what is the purpose of substance X? Why do we use quicklime? The main purpose is to dry ammonia gas because this ammonia contains steam. It is condensed even from here you can see.

[00:06:26]So, it contains steam in it. So, we use this substance X such that when ammonia is coming, by the time it passing it it is passing through X, it gets dry.

[00:06:40]So, we use substance X to dry ammonia.

[00:06:43]So, our two here will be simply to dry ammonia.

[00:06:55]Okay? Then, the next question, why is ammonia collected by using the method shown up above and not above water? So, there is no water in this uh setup. Why not above water? That's the question. So, the question The answer is simple because ammonia is highly soluble in water. So, suppose we we we add water here, it gets collected over water. How it can't even get collected because it will dissolve in water. Okay?

[00:07:27]So, that is the reason we we use this.

[00:07:31]So, you will say this is C because ammonia is highly soluble in water. That is the reason.

[00:07:53]Then the other reason, because it has two marks, so you can include it. The other reason, this method they are using is It has two names depending on what you use, okay? So, the first reason is I mean the first method the first name of the method when you see like this apparatus here the the opening is down. Okay, the opening here. This is the entrance. It is down.

[00:08:24]Then ammonia is going upward. This is upward [clears throat] delivery or at the same time you can call it what?

[00:08:31]You can call it downward downward displacement.

[00:08:36]Two names. So, we use this at the same time because ammonia is less denser than what? Than air.

[00:08:43]So, that's why it is like this. Because if we let it if we use if it was opposite the other way, it can diffuse in what? In air.

[00:08:55]But we use this because ammonia is what?

[00:08:58]Is less denser than air. So, you can also include this reason.

[00:09:03]Because ammonia is less dense than air. But the question needs this answer mostly because it is talking about water. So, this is also an answer.

[00:09:23]Then describe the chemical test for ammonia.

[00:09:28]The chemical test. So, ammonia is a base is an alkaline.

[00:09:33]Okay? So, once you understand that it is a base you need to know the test for for a base.

[00:09:40]And bases, they turn red litmus paper blue.

[00:09:45]Okay? So, describe the test for ammonia.

[00:09:48]This is our D.

[00:09:50]You simply say, "Add a red a red what? A red litmus paper to ammonia."

[00:10:07]Then you conclude, "The red litmus paper turns blue."

[00:10:18]Turns blue.

[00:10:20]So, ammonia turns red litmus paper blue.

[00:10:23]Then, the last question now.

[00:10:26]State two uses of ammonia. So, two uses of ammonia. So, ammonia is used in many things. And this question, you need also to know it because it is very important.

[00:10:36]So, number one, to manufacture nitric acid.

[00:10:50]Nitric acid, also to make or manufacture explosives like fireworks and all those explosives.

[00:11:02]Yeah. Then, also to make fertilizers.

[00:11:11]So, these are enough for for for this question. They only need two.

[00:11:16]Now, let's look at the industrial preparation because this is done for the laboratory preparation.

[00:11:22]How do we prepare it in the industry?

[00:11:25]So, in the industry in the industry, that is now Haber process.

[00:11:31]So, the main things that you need to know actually it is a simple process. You just have to master it. Okay? You You have to master it. It is very important.

[00:11:41]So, in the industry, the Haber process, we don't use this and this to produce this. We use other reactants. Okay? So, we use only two reactants, nitrogen and hydrogen. So, this you must know.

[00:12:00]So, let me write for you. This is the reaction. The reaction always it is nitrogen plus hydrogen to form ammonia.

[00:12:20]So, this is the word equation. Sometimes they ask word equations also.

[00:12:24]Now, this is the the the what? The the the word equation. But, the chemical equation, nitrogen N2 N2 reacts with hydrogen H2 to form what?

[00:12:39]Ammonia NH 3. So, we need to balance it up. We have three hydrogens here. So, I mean we have two nitrogens here. We start with nitrogen. So, even here add a two. So, nitrogen balances up, but hydrogen becomes three multiplied by two six. So, to make this six, we need a three here. Three by two, this is also six. So, this is balanced.

[00:13:05]This is a gas.

[00:13:07]This is a gas. This is a gas. This is Haber process. So, sometimes what they do, they will remove hydrogen and put put any letter. For example, X or Y or Z. Then, they ask you what is this?

[00:13:22]Okay? So, that is very important to know. That question they've brought it before. They put X here, then they asked to find X.

[00:13:31]So, that is very important. The other important aspect under this this this process, Haber process, is the conditions.

[00:13:41]So, conditions.

[00:13:45]These ones you shouldn't forget. You should note them down. They will bring.

[00:13:50]So, the conditions that are needed actually this is a reversible process.

[00:13:55]So, the arrows should be like this.

[00:13:59]This arrow is like this.

[00:14:02]Even this one is like this.

[00:14:04]Yeah. So, when you see this just know that it is a reversible reaction. A reversible reaction is the reaction in which the product can decompose and become reactants.

[00:14:17]When reactants react to form products, the products can also go back to the reactants.

[00:14:22]That's what happens. So, number one, we need a catalyst.

[00:14:31]So, catalyst, the catalyst we use is iron.

[00:14:37]Very important. So, note this down. The catalyst is iron. Then, the temperature Temperature is about 4 50° or you can just say 450°.

[00:14:56]So, degrees Celsius, yeah.

[00:14:59]Or you can simply say 350° to 450°, they'll still mark you.

[00:15:04]So, because it varies, yeah, it varies from 350° to 450°.

[00:15:09]Then, the last one now is the what?

[00:15:13]Is the uh the pressure.

[00:15:18]So, for pressure, we measure it in atmospheres. It is 200 atm atmospheres.

[00:15:30]So, these are the conditions. These are very important, very important. So, this is basically Haber process.

[00:15:39]They will ask you this equation to write it yourself and to balance it.

[00:15:44]Okay? Then they will ask you the what?

[00:15:46]The conditions. So, these are very important things to know. So, this is preparation of ammonia. Hopefully, you've gotten all the concepts and you've understood. Don't forget to subscribe.