L-32 - NIPER JEE 2026 | Pharmaceutical Analysis: Mass Spectroscopy | 360 Series #niper #niper2026

Added: 2026-05-26

[00:00:01]Hello dear students welcome to all GD YouTube channel and today in this video we will discuss important questions of Mass Spectrometry for our NIPER exam in our ongoing 360° degree series.

[00:00:16]If we talk about analysis, then going forward in Sniper, brother, you are going to get a lot of instrumentation methods.

[00:00:25]So what happens many times is that in the NIPER exam, many questions come from our analysis. Ok? So we have to proceed with the belief that brother, you have to study well. You will revise properly whatever you have studied in the exam.

[00:00:38]In this, you should not think that brother, what happens many times, we may get to see many questions and basic questions come in it.

[00:00:48]You should have basic knowledge of every method. So if we talk about mass. Mass spectrometry takes place. First of all, brother, we do not use electromagnetic radiations in this.

[00:00:57]Here we depend on ionization. Many chemicals get ionized.

[00:01:02]Sometimes ionization is done through electron impact. This is just a simple example. If a high speed car goes and hits the wall. First of all, a crack appears in the wall. Then the wall breaks into pieces. This is how our month is, brother. Electrons go to 22. Get it done through molecules. So first comes your crack at the molecules.

[00:01:23]Meaning a charge comes on it. First it gets ionized and what is formed is called molecular ion. called parent ion.

[00:01:30]Papaji says Ayan. And whatever molecular weight of that ion, whatever m/e ratio comes out, it is equal to our molecules.

[00:01:39]Then energy is again given to it from the electron. Then it breaks into pieces.

[00:01:44]Fragmentation occurs. What do you do with those pieces according to their mass up charge ratio? Let's separate them.

[00:01:50]Through this we get all the information like molecular structure, molecular formula etc. It is called fragment ion. The graph of this mass is formed, the graph of relative one density versus m/ e ray is formed, my brother, the highest peak in this is the most intense peak, the tallest peak is called the base peak. If someone asks which has more molecular weight? Whose m/e is higher? So molecular ion will come.

[00:02:19]In many cases, if you have an isotope ion, then in the case of m + 1, it may be more.

[00:02:25]But if we want to see the height of the base peak, its abundance on the y axis is 100%.

[00:02:30]Keep this in mind. Look, it is written here that mass spectroscopy work is on the basis of this, it is a very easy question brother. What does it work on? We know very well that our mass spectroscopy works according to the mass upon charge ratio. So here you can see anywhere what is written, in this question you will have to look a little here, charge up mass, okay it does not depend on charge alone, son, mass does not depend on charge alone, here charge up mass ratio is written, it depends on the function group, so the correct one here will be mass/charge ratio, you will have to change it here, our mass/charge ratio will be correct which we call m/e ratio or m/z ratio. So this answer of yours will be corrected by us.

[00:03:19]Mass/Charge Ratio The highest mass to charge ratio, if anyone ever asked, is that of a molecular ion. And in many cases if the isotope is m + 1, m + 2 or m + 3. If asked in the graph, who has the highest 100% abundance? The largest abundance is of our base peak, it is called the most intense peak.

[00:03:44]Brother, whatever answer is given here, you will correct it. Mass up charge ratio our answer will be correct. Mass up charge ratio will be correct. The next question is what is the use of mass spectrometry. Brother, in which phase is mass spectrometry done? Brother, yesterday someone asked in which form UB Bizwill runs? Bhaiya, you say that you need a diluted sample of Vimul, according to the Beer Lamb's law, IR says bring whatever it is, I can analyse everything. The form in which we put the solid, liquid, gas in the instrument is called UV. Brother, tomorrow you will ask about paracetamol, so sir we did UV also, so brother you took its diluted solution in a tube and put it in, so the form in which the result is shown in the instrument is its form, so you have to remember this here.

[00:04:35]If someone asks you about mass, there your vapor state is gas state. If NMR is asked, liquid sampling is done. If someone asks about ESR, it is solid, liquid and gas. ESR contains solid liquid gas like IR.

[00:04:51]Apart from that, nephroturbines are for their suspensions.

[00:04:54]So you should remember this a little bit.

[00:04:58]Polarimetry is for optically active compounds. So whatever answer you get here, your gas phase will be absolutely correct. Our answer will be gas phase. The sample here in mass is our sample in vapor state.

[00:05:08]In which form does it happen brother? Vapor state contains its own sample. Have to be careful. Now comes the next one, this question comes up a lot here.

[00:05:17]What is soft ionization technique? Soft ionization. Ok? Whatever you have here, whenever we read Mass, look, we have an electrode impact in it.

[00:05:26]Electrospecific ionization occurs.

[00:05:28]Ok? Our chemical ionization occurs.

[00:05:31]These ionizations are hard ionization techniques. Many times he asks, look at soft ion, the main technique of soft ionization is Bhaiya Malti's name. Ok? Matrix Assisted Laser Desorption Ionization.

[00:05:46]Electrospray ionization. Ok? This is yours brother, our electrospray ionization. Here we have chemical impact, which is your electron impact or electron specific ionization, if it is written electrospray or MALDI, these come under our soft ionization techniques because here in the question he is not even talking about soft and hard, leave it aside, he is asking son where does ionization happen, in which world does ionization happen, this is a simple question, okay, so there is no tension here, see atomic absorption spectroscopy IIR NMR, the main thing depends on ionization.

[00:06:25]Ionization is the first step and fragmentation is the second step. Where do we get this? Available in the month. And if he asks, brother, which is soft ionization in this? So MALDI and electrospray ionization are our soft ionizations. Ok? Now comes the next electrospray ionization here where is your common interferences colorimetry NMR brother?

[00:06:48]Electrospray ionization. So this is a very easy question. Where does ours stand? It happens in a month.

[00:06:54]Where does electrosphere ionization occur? It happens in a month.

[00:06:56]If someone asks about fluorimetry, I would say emission spectroscopy. If we talk about fluorescence, then the strain here is light mate.

[00:07:05]Phosphorescence has after sum.

[00:07:08]Look at this if someone asks about the transition from singlet excited back to singlet ground.

[00:07:13]And if you are asked here then in this it comes back from singlet to phosphorescence state. This process is called our photosensitivity.

[00:07:24]Pay attention here carefully, this is an example of emission spectroscopy. Here the question arises, what is Stokes fluorescence? Brother, this is a normal process. Brother, if we get less energy than what we gave, then we will call it stock flow. If more energy is emitted then it will be called anti stocks, here we and you, which basically sometimes become equal.

[00:07:48]Ok? So those that remain with us are called resonance processes. Similarly, in Raman scattering you get strokes, lines, anti-wave lines and relays.

[00:07:57]So remember that brother, they ask us in the exam. Ok? Everyone knows NMR. Using radio mix to determine the type of nucleus. Everyone knows IR. Please remove the function group and give it to me. Brother, vibrational transition is mainly taken into consideration in this. Now comes the use of waves in mass spectroscopy. Brother, now he has asked, son, look, waves are not used normally. Now you accept it, look, I told you how far our world extends? There are only up to four options. Let us see, brother, radio waves are used in NMR. Ok? This will not happen.

[00:08:31]IR is used in IR. There is vibrationoscopy. Microwave ESR occurs. Here our electron beam is used in the form of energy in mass. Approximately 20 electron volts are required when we initially ionize. When fragmentation is to be done, we use approximately 60 to 100 electron volt energy.

[00:08:53]So what will happen to our D option here? It will be corrected brother. Ok? The next question comes. There is a McClafferty arrangement. It is present in the alkene molecule. very good thing.

[00:09:03]Ok? Now look at the loss of cyclic arrangement, if you have any molecule in this form, if it is in any such form, it may have a double bond or it may be in any form, here if you have this condition, here the alpha carbon, this beta carbon, apart from this there is another carbon, gamma hydrogen, okay, in this our beta bond breaks, okay, our beta bond breaks, remember it well and there is shifting of gamma hydrogen, so what is written. Look, whose rearrangement is happening here brother? Alpha does n't have it, Beta doesn't have it. It belongs to Gama Bhaiya.

[00:09:39]Gamma hydrogen shifting occurs and one of our in and enol radicals become our. So gamma shifting of hydrogen occurs. Keep in mind that it is available in unsweetened form. Bond is our break.

[00:09:51]What do we call this? It is called McAlfarents. The ion formed is called the rangement ion. Now see, this question comes like m/e ratio for the butyrophenone according to the McLafferty arrangement, m/e ratio is being asked for butafenone, so we will have to first make the structure of butafenone, brother, what is butaphenone and I have to tell you about it according to the m upon Ire, I have to tell you directly 132, look, I have to tell you about our butaphenone, brother, so here in the butaphenone, the gamma hydrogen will shift, there will be cleavage of our alkene fragment, brother. Ok?

[00:10:28]So in this way, whatever our m/e will be, its karestetic rangement ion will be 132. So sometimes it happens that the pigmentation inside the mass may raise questions.

[00:10:39]The chances are very less. Ok? This is a random process for you brother.

[00:10:46]You cannot impose any such rule or regulation for this. Mass Spectroscopy Which of the following pathways involves double bond in gamma hydrogen? Then everyone will become your brother. Gamma is hydrogen. Beta Bud is about to break.

[00:10:58]What should I say to him? McFarth Regiment to speak. What do you want to say brother? We call it a McFert arrangement.

[00:11:05]Now comes the cataclysmic feature of the base peak.

[00:11:08]What is base peak, son? The one which scores 100 is called base peak. The most abundant peak is called the base peak. The tallest peak of our Mount Everest is called Base Peak.

[00:11:19]What generally makes up a base peak? Make Tatains.

[00:11:22]Ok? So you have to keep this in mind.

[00:11:24]Base peak is our most intense peak.

[00:11:26]So your answer will be absolutely correct.

[00:11:29]Look, the molecular ion peak, the m/e ratio of the parent ion, tells the molecular weight. Generally it is more. The isotope goes behind on the bus.

[00:11:38]Look, it is written highest m/e value. What is its exception? If there is an isotope, it will be available.

[00:11:45]What is base peak? Height is the highest abundance. Fragment ions are called matter ions.

[00:11:50]Any of these basic metastable ions is a short lift ion that does not reach. Non integral m + 1 m so these are our isotopes. Explain the interface applied between LCMS instruments.

[00:12:01]Now this LCMS which is hyphenated technique, we will call it brother.

[00:12:06]What will you say? What would you say to the LCMS? It is a hyphenated technique. LCMS is our hyphenated technique, brother. Here liquid column chromatography with mass separator. Ok? Injector ion source is a very easy question. Whatever is written in front is our answer brother. Ok?

[00:12:24]You would call this hyped technique here. This is basically our column and what is the mass here? We are capturing the ions.

[00:12:32]So here the LC chromatography is doing our separation of ions. What is your final ions that you are generating and giving us? Mass. What will this be your answer? In this our C answer will be corrected. Ok? You have to keep this in mind. Let's talk further.

[00:12:51]Whatever your LCMS is, brother, it is our chromatography system. The mass spectrometer remains. So here your chromatography separates it.

[00:13:00]MS is generating and providing its ions.

[00:13:03]Most intense peak in the spectra. Tell me brother, who has the highest m/e value? The molecular ion is of the parent ion. The base peak is the most intense.

[00:13:13]What is a fake peak? The tollipped peak is a metastable peak. The parent ion itself is called the molecular peak. Meaning, options A and D are the same for you. What is left for us in this? Option B will be absolutely correct. Let's talk about the next thing. Which of the following pictures will be observed in the mass spectra of a compound containing a chlorine atom? He is asking for chlorine, son, you tell me. What about chlorine?

[00:13:37]What will be our peak due to chlorine? Look, there is chlorine, we know brother, there is chlorine, 35, 37, these are its isotopes.

[00:13:45]You can go and take it out accordingly. This is m + 1 m + 2, right? You will get this, you will get this pick of chlorine. m + m will give m + 2.

[00:13:56]35 happens, 37 happens. Now if someone asks us about carbon, we will say that we will get m + 1. It contains 13.

[00:14:04]We have to remember that m+ will be added to the peak of the isotope.

[00:14:07]Ok? This will be m + 2 brother. 1/3 edge a large of m. Ok?

[00:14:15]You will get this here, brother, we will get it directly because of isotope. We will see m and m + 2 in this. Ok?

[00:14:22]Remember this. All these options that are there in this will not be available here. It will remain straight. Ok?

[00:14:28]So m + 2 is a large of m. Ok? So this will be your option, you will have to make it m +3. The answer here will be seen in the m and m + 2 peaks. Now comes the mass spectrometry presence of the chlorine.

[00:14:41]Brother, I just saw this question and your answer is the same. Ok? Its ratio is, son, you will get it in infinity of 1:3. That's what I was saying. There was a divider there.

[00:14:50]This does not happen. So the answer you will get here will be m + 2 brother.

[00:14:56]You will have to correct the option here also.

[00:14:59]You will get m and m +2 brother. If it is chlorine then you will have to write m and m +2 brother. Ok? This will be m and m + 2 in your answer.

[00:15:08]Ok? m and m +2 will remain brother for my chlorine.

[00:15:12]Ok? So what happens? The paper of the sniper is memory based.

[00:15:16]We also have options. The language of the questions is also memory based. So what happens to you in this is that many times we ask you above, what question came, then you guys will tell, then I will tell roughly, so if it is about chlorine then it is a simple story, m and m + 2, in both the questions I told you m and m + 2, our m will be there and m + 2 will be there. Next question is brother mass spectrum base peak. Base peak comes a lot brother. The base peak is the topper, the man is getting 100%, the highest is the abundance with the low intensity, not brother, high intensity, abundance with the medium intensity, not brother, he is a big man, abundance with the high intensity, our C option will be absolutely correct, base peak comes a lot, the most favourite question of the mass, base peak comes now, then the intensity for base peak comes, 100 marks are coming, brother, what is your intensity of base peak, it is 100%, yours is going to be 100%.

[00:16:16]Most of the questions come on these ions only. The molecular ion parent generally has a high m/e.

[00:16:22]Except in the case of accept isotopes. Ok? You have to keep this in mind. This is what is made in the first step. Then fragmentation occurs. Fragment ions become data ions. Metastabiline does not reach the detector. There is a shortlift.

[00:16:33]When will m + 1 be found in general? It will be found in isotopes. In which one is it available? Look, you will find it in chlorine. It will be found in carbon. In hydrogen, in nitrogen.

[00:16:42]In which will m +2 be found? You will get it in oxygen brother, it goes straight from 16 to 18. You can find it in chlorine, you can find it in sulphur. So this is the question he asked you brother, what I just saw in the sniper, brother, you will ask which one will I get for carbon? So we will get m + 1 brother. For hydrogen, m + 1 can be obtained.

[00:17:01]m + 2 can also be found. Because your tritium is also ours. Ok?

[00:17:05]For nitrogen we get m + 1. If we ask about chlorine then m is +2. You will ask for sulphur, your m is +2. So this gives you m +2 ours. This needs to be taken care of. Now comes the bombardment of electrons produced from various types of sources. Where do those electrons come from, son?

[00:17:22]From tungsten flame, to hottest tungsten flame, to radium flame. So what happens to your tungsten flame here? Our electrons are released.

[00:17:31]And what do they do? Have energy.

[00:17:33]Around 20 to 100 electrons, ionization has to be done around 20 and what has to be done with 70 to 100? Do fragmentation.

[00:17:41]So our answer will be correct. If you heat it, electrons are generated from there. Mak elimination happens. Neutral molecules take place from the aldehyde is, benzene is your hexane is. Look where does amide, hexane come from? So ours gets directly converted into benzene.

[00:17:58]Ok?

[00:18:01]Remember the rule of Maclap Regiments well that whatever our compound is, it does not matter here, son. Ok? If you understand the questions correctly.

[00:18:12]Ok? The question was right in its place. Will there be benzene or not? Look, benzene will be the answer only if it is done in this manner.

[00:18:19]Brother, there must be some carbonyl involved.

[00:18:21]Now here x can be anything.

[00:18:23]Add chlorine, add OH, add H, add CH3. It can happen to anyone. It can be ours in anyone. Keep in mind this can happen to anyone. Take good care brother. Ok?

[00:18:40]Here comes Joe McPherty's question anytime.

[00:18:42]Look, options don't matter son.

[00:18:44]And what answer was given in this also does not matter. We have to cover things and we should not make any mistake in the final exam.

[00:18:51]Look at what our McLaufed arrangement requires, which compound will have it. A compound containing a carbonyl group in any form.

[00:18:59]Your X, whether it is in OH form or it has amine attached here or it is aldehyde or it is ketone, any, ester or anything.

[00:19:09]This carbonyl group is essential.

[00:19:11]Apart from this, the carbon here should have at least three carbons. There should be three carbons.

[00:19:16]Alpha carbons these beta carbons and these gamma gamma's being hydrogen on hydrogen. It is mandatory to have hydrogen on gamma, brother. What is it like to have hydrogen on gamma? It is mandatory brother. It is mandatory to have hydrogen on gamma. Ok? And when this works, the gamma hydrogen shift happens here. So in this way our hydrogen gets shifted here brother. Ok? And from here this bond is your beta bond. This beta bond breaks on its own. So one of ours lives here. Ok? In this way, your inol radical becomes ours and here we have an inan. In this way it becomes double bud. So this remains.

[00:19:56]Now as asked in the question, brother, Macleod element elimination of the neutral molecules takes place from brother, will yours be from the carbonyl compound. Now which one is it? Like aldehyde your answer can be correct. Ok?

[00:20:12]Your chances of getting benzene are decreasing because there is no carbonyl group. Hexane will not be ours. This is our saturated compound. May be amide. Look, if it is amide, this is amide, my brother. Now suppose there are three carbons here and hydrogen on gamma, then see what the conditions say?

[00:20:28]Should be carbonyl and our gamma pay.

[00:20:31]Now like this question. In this we can go to two options. In this you will have to add up the options. Brother, it must be caldehyde. What should be included?

[00:20:41]Gamma would be hydrogen. Then your answer will be the best. What will that be considered our answer? It will be considered the best. Ok? So it is present in carbonyl compound, son. The answer to the benzene written here will not come. The carbonyl will come. Could be an aldehyde, could be an amide. But what should happen? Gamma Per Hydrogen should be ours.

[00:21:00]Ok? Keep this in mind. Brother, next question. Which of the following solvents is used in the molecular ion peak will not be eluted?

[00:21:07]Ok? In which of the following solvents does the molecular ion not peak? Does not appear in Aminas. Does not appear in aldehydes. Does not appear in acetone.

[00:21:15]Aldehyde does not appear in acetone.

[00:21:17]So this is where alcohol comes in. Remember this.

[00:21:19]Our molecular ion peaks in alcohol are not visible. Ok?

[00:21:26]Many times we do not see the molecular ion peak in our solvent which is alcohol.

[00:21:28]Like alkane, ester, we do not see them often in alcohol. Next is mass spectroscopy also called narrow spectra, broad spectra, positive ion spectra. In this, only Beta Catayan is dominant. Ok? Cation is formed in it.

[00:21:43]Be it a molecular ion, be it a data ion, be it a fragment ion.

[00:21:47]Cations dominate. So we call it positive ion spectra.

[00:21:51]For excitation of the neutral atom we use the electromagnetic radiation. Ok?

[00:21:56]You can do electron bombardment brother.

[00:21:59]If we have any molecule, we have to excite it in mass. So this has to be excited.

[00:22:05]Brother, you should especially write mass in the question. Then there will be an answer.

[00:22:08]We don't have any intuition that we will know. There is talk of mass that there is talk of UB IR. Brother, you can get excited by anyone. It could be due to radiation.

[00:22:18]In electro, he is asking there in the mass, what do you want there in the mass?

[00:22:24]We will need electron bombardment. Brother, you can also use electromagnetic radiation to excite any atom.

[00:22:30]So it must be written here brother.

[00:22:32]Mass will be written in the question. So whatever happens here, your answer will be B, normally see, our vibrational energy which is IR, okay, excitation can happen from visible radiation, but how does it happen in mass, our neutral atom gets ionized, molecular ion will be formed, then your fragment ion data remains in it, there is bombardment of electrons, so your B answer will be absolutely correct, okay, so we discussed all these questions, children like you feel that all the macro elements create problems for us. Then we have a problem with fragmentations. Look, fragmentation is a total random process.

[00:23:14]Suppose someday in a question, suppose they asked you a question, what is the m/e ratio of the base peak in benzophenone? So brother, do not try to solve this question at all.

[00:23:25]Sometimes a few questions come up.

[00:23:27]So don't worry about that.

[00:23:29]Because look, fragmentation is a total random process. Remember the Maclabadi elements well brother. Like our carbonyl.

[00:23:35]Here x can be anything brother. OH it could be. It could be your H. It could be CH3.

[00:23:41]Our Aster might as well.

[00:23:44]All these things can happen. If this remains then it is ester. This is a ketone. This is an aldehyde.

[00:23:49]This has become ours and yours. If NH comes then it will become amide. This is it. The second thing is that here you should have at least three carbons and it is mandatory to have hydrogen on your alpha carbon, beta carbon and gamma gamma. This is the requirement. When this happens, one of our enol free radicals is formed and the other one of ours is formed, in this way your double bond enol compound is formed. So remember the rearrangement ion that is formed in Macleod elements, brother, gamma hyo is mandatory on that. Ok? And secondly, it is mandatory to have a carbonyl group in it. What will happen to us in a similar compound?

[00:24:30]McLafferty will be the arrangement. Gamma iodogen shift occurs. Beta bonds are our break.

[00:24:35]Ok? You should know this.

[00:24:38]And if you look at the questions coming in the month, most of them will ask about graph, then we know that it is relative vandalism versus m/e ratio. The highest peak in this is the base peak. There is the most intense peak. If you are asked about molecular ion then m/e is high. But sometimes it can happen in the case of isotopes.

[00:24:55]That will become more.

[00:24:58]So remember this a little bit and what is an isotope peak? What is a metastable peak? All these are asked. Do this complete revision in this manner. If a question comes, you will be able to answer it easily. So this is a little bit you have to remember. Ok?