Short video explaining milliequivalents (mEq) and how to convert from mg to mEq. It will help if you have viewed the introduction video before viewing this.
Dr. Brad, going into my 4th year of a PharmD program and just found this video extremely helpful in refreshing my Meq skills. Loved how you broke it down with the eggs and coffee beans. Much appreciated thank you so much Dr. Brad
Hi Catherine. So happy I could help. Let me know if you have any questions. Also, if you email your questions to brad.wojcik@gmail.com, it is easier to answer. -Dr. Brad
Thank you so much for making these videos for pharmacy technicians your helping me understand it way more on the math an I'm about to take my nationals test really soon an i'm feel a lot better now because before i was little more confused but now i feel so much better thank you.
Thank you so very much Dr Wojcik your tips and way of looking at certain problems is very insightful. I will be starting pharm tech school in a while and i really enjoyed your videos so far. you would be a really bad ass chem professor. thank you very much again.
Very helpful explanation. I never used mg/mmol (only used g/mol) in chemistry so I was confused at first about it, but it makes more sense now that you explained it.
Thanks Steven. I think that all of us who started off in chemistry thought in terms of g/mol. When I first started teaching this, I would have the students start off in g/mol then change to mg/mmol, then it dawned on me to just have them go straight to mg/mmol because it is the same numerical value.
For that last step in which you solved for mEq I found a formula, just in case anyone wanted to use it. mEq=(substance in mg x valence #)/atomic weight
Pharmacy tech here. Had an out-of-stock situation today with a med commonly measured in mEq. Patient came to pick it up along with its paired diuretic. At the counter, during rush hour, the following ensued: "Don't have my potassium?? That's alright, I'll just grab it otc; how many mg did the doctor write it for?" Apparently it would have taken me the same amount of time to do the math as it would to call another store! I smoothly dodged his question by choosing the latter. Thanks, though, Doc!
Sir last part cant understand sir also sir meq is said for single ion ..i.e example we cant say meq of kcl is 100 but we xan say meq of k is 100 i.e meq cant be found for molecule but only for single ion ..
Hi Tonderai. You are starting with 50 mEq Ca ++ and need to change that into mg of CaC03. Since Ca++ has two charges, you will get two mEq from each millimole (mmol) of Ca++ ions. Looking up the atomic mass of CaCO3, we see that it is 100.09. This means 100.09 g/mol and 100.09 mg/mmol. Now just line everything up so that the units that you don't want cancel out and you are left with the units you want. 50 mEq(1mmol/2 mEq)(100.09 mg/1 mmol)= 2502.25 mg or 2.502 g.
Thank you Dr. Brad for this answer. I still have one question about this solution. When you line everything up, the unit of 50mEq of Ca++ can be cancelled out with the unit of 2mEq Ca++, so how can we cancel out the unit for the rest? Can I think as (100.09mg of CaCO3/ 1mmol of Ca++) so that the Ca++ unit can be cancelled out? or should it be (100.09mg of CaCO3/ 1mmol of CaCO3) ??? Thank you so much.
Hi Krystal. In the above problem the mEq units on 50 mEq are canceled out by the mEq on the 2 mEq and the mmol units in the 1 mmol/2 mEq are canceled out by the mmol units in the 100.09 mg/1mmol. It is true that you could use 100.09 mg CaCo3/1mmol of Ca++, but I think it is easier to understand if you add a ratio at the end of 1 mmol CaCo3/1mmol Ca++. This is what the problem would look like if you include all of the chemical formulas. 50 mEq Ca++(1 mmol Ca++/2 mEq Ca++)(100.09 mg CaCO3/1 mmol CaCO3)(1 mmol CaCO3/1mmol Ca++) = 2502.25 mg CaCO3. It is a little confusing if you use 100.09 mg CaCO3/1 mmol Ca++ because the atomic mass of CaC03 is 100.09 and it is easier to explain this way. I hope this helps. Let me know.
How did you get 746mg in the beginning of the equation? The only way I figured out how you got 746mg was after adding 39.1 + 35.5 = 74.6 x 10 = 746 , but where do you get the 10 to times the 74.6? thank you
That was just the weight that I chose as an example to change to mEq. I could have had a problem like, How many mEq are in 1000mg. I just chose 746 mg because it would come out to 10 mEq. I looked at the video again, and I should have added something like, "let's do a problem where we calculate how many mEq are in 746 mg of KCl. Sorry for the confusion.
Hi Rajiv. Thanks for the nice comment. There is no simple conversion between concentration and mOsm because you are working with the number of particles in the solution and you have a number of factors that will affect this. Maybe I will do a video on this, but for now just google it and a lot of good info comes up.
hi Dr.Brad, I really find it difficult when it comes to computing meqs. I keep on researching and watching videos on youtube just to fully understand but I really can't cope with it. I am now reviewing for boards and I really wanna know about this one. no matter how I try, I am still getting the wrong answer this is the formula that they gave us during review days meq=mg/MW x factor. some articles says valence instead factor. what was the simplest formula in getting meqs for solving board problems? thanks for helping!
+Ayang De Los Santos Hi Ayang. I don't like those formulas. All you have to know is that a mEq is a mmol of charges. If you learn a few terms (mole, mmol, atomic mass (atomic weight), these problems are very easy. I have a mEq exercise that goes step by step. Please send me an email at brad.wojcik@gmail.com and I will send it to you. Of course anyone else who would like this material can email me also. -Dr. Brad
+Ayang De Los Santos Hi Ayang. Here is a link to the dropbox which contains the exercises. Also, be sure to download the handout book which explains everything. Let me know if you have any questions. It is easier if you email me any specific questions. brad.wojcik@gmail.com www.dropbox.com/sh/90xs9qsjsugdy5a/AAD1pPnpo59HSU_RAYLgqekDa?dl=0
Problem 1) You have to change 9 mEq Ca++into mg. There is 147 mg/mmol and each mmol has 2 mEq because there are 2 charges on Ca ++. 9 mEq (1 mmol /2 mEq) (147. 0 mg/mmol) =661.5 mg. Problem 2) same as problem 1 except you are starting with 7 mEq. There are still 2 mEq /1 mmol because you have 2 Cl- per molecule. 7 mEq(1 mmol /2 mEq)(147.0 mg/mmol) =514.5 mg.
so say we had potassium sulfide, would it be 2 meq/1 mmol? Do we always choose the highest charge in the compound and ignore the lowest? Since sulfur is -2 while potassium is +1.
Hi dim. Well, let's use K2S04 as an example because K2S reacts with water to form KSH and KOH. 1 mmol of K2SO4 will yield 2 mEq of K+ because you get 2 ions from each molecule and you would get 2 mEq of SO4-2 because you get 1 ion, but 2 charges. It is easiest to think of a mEq as a mmol of charges. You get 2 mmol of charges from the K+ and 2 mmol of charges from the SO4-2. You have to look at both ions. Hope this makes sense.
Hi Dim. It is 1 mEq of K+ and 1 mEq of Cl-. You can say that you have 1 mEq of KCl or you can say that you have 1 mEq of K+ and 1 mEq of Cl-. You have to talk either about KCl all together or K+ and Cl- separately.
dr brad thank you for the good work my question is about m mol and m osmol what is the difference ,i revise the issue in comprehensive pharmacy review but i can`t apply it to cholesterol conversion from m mol to mg/dl something is missing!!!
Hi Amr. The basic difference is that a mmol is 1/1000 mol of anything. If you have a mmol of NaCl, you have 6.022 X 10^20 molecules of NaCl and the same number of Na+ and Cl-. A mosmol is a mmol of particles. So, a mmol of NaCl would be 2 mosmol because you have a mmol of Na+ and a mmol of Cl-. Going from mmol to mg/dl would not involve any osmotic calculations. You just need the molecular weight of cholesterol and the volume of solution.
The problem was in my approach i was trying to apply the mlosmol equation to the conversion . In another instance i can convert it easily by recalling conversion factor of cholesterol but I want to know how to calculate it my self. So the given was solution contains 4m mol of cholesterol , also he gave me mol wt 386 and ask for how many mg/dl in the solution
You can download my book, Pharmacy Calculations for Pharmacy Technicians: Solving Pharmacy Calculation Problems Without All the Silly Formulas, for free at payhip.com/b/5xVY. It goes into more detail than possible on the videos and is full of practice problems and answers.
I am a failing student but i appreciate how you said sorry Avogadro haha. still trying to figure it out but you seem like a good teacher. wish me luck on my exam tomorrow i'll need it
Hey Dr. Brad Im not sure I got a few curve balls I didnt expect but I might have done enough to get a passing grade hopefully. I'll find out my grade next thursday
HELP.. a solution of potassium phosphate contains a mixture of 164 mg pf monobasic potassium phosphat(m.w=136)and 158 mg of dibasic posassium phosphate (m.w=174) per milliliter a-how many milliliter of solution should be used to provide 45 mEq. of K+ b-how many millimoles of total phosphate will be represented in calculated volume
yasser martians Hi Yasser, The monobasic his KH2PO4, so 1 mEq/mmol. The dibasic is K2HPO4, so 2 mEq/mmol. 164mg(1mmol/136mg)(1mEq/mmol)= 1.2 mEq/ml for mono. 158mg (1 mmol/174mg)(2 mEq/mmol)= 1.8 mEq/ml for dibasic. So, you have 3 mEq/ml 45 meq(1 ml/3 mEq)= 15 mL. Mono has 1.2 mmol/ml, dibasic has 0.9 mmol/ml. 2.1 mmol/ml (15 mL)= 31.5 mmol Phosphate.
i feel like a complete idiot in comparison with others commenting here that seem to find this clear and helpful. This video just doesnt seem either CLEAR, or specific enough...in watching it, ..i feel like there is something everyone else knows or its assumed we should know ...but i dont...I wish i could target exactly WHERE or how my confusion falls into play...i cant. i just dont feel like enough was explained. maybe im just stupid. : ( I DO undertand the ONE millimole and TWO millimole concept, but i think if we had a video based on exact examples? and ...maybe a bit more detailed explanation?? i dunno. : (
ok in going BACK over this video I figured out somethings about where i am confused, and in case someone else goes through the same stuff they can see they werent alone. The CONCEPT of mmol, mol etc, are wonderfully explained, even the atomic mass thing, but, when I was learning how to calculate for everyday practical mEq answers (vet tech stuff( I DONT remember in the ER nor in the classroom back in 99 ever having to learn/reference the periodic table to find numbers to calculate....is there a different video on here? am i missing something?! When tested, on a computer for two hours to pass the PCTB exam to get my CPhT; how will i be able to reference the PERIODIC table? Are these examples based on what I will be tested on? I cant put my finger on my confustion STILL lol! : l
Oops, I wrote mol when I should have written mmol when I was talking about Ca++.
noticed that. :) thanks for this comment that clarified the confusion.
Thank you so much for taking the time to make this, you've made prepping for the exam a breeze!
Glad I could help! Let me know if you have any questions
Dr. Brad, going into my 4th year of a PharmD program and just found this video extremely helpful in refreshing my Meq skills. Loved how you broke it down with the eggs and coffee beans. Much appreciated thank you so much Dr. Brad
Hi Nico, Glad you found it helpful. Non if this stuff if very hard if you know what you are actually doing.
I have a final exam next week in this, and I have been near tears trying to get it straight in my head...I think I am finally there.thanks!
Hi Catherine. So happy I could help. Let me know if you have any questions. Also, if you email your questions to brad.wojcik@gmail.com, it is easier to answer.
-Dr. Brad
Thanks doctor for helping me out with the calculations.
Thank you so much for making these videos for pharmacy technicians your helping me understand it way more on the math an I'm about to take my nationals test really soon an i'm feel a lot better now because before i was little more confused but now i feel so much better thank you.
Hi Chelsea. Glad you found them helpful.
Thank you so very much Dr Wojcik your tips and way of looking at certain problems is very insightful. I will be starting pharm tech school in a while and i really enjoyed your videos so far. you would be a really bad ass chem professor.
thank you very much again.
Glad I could help. Be sure to download my book at Payhip.com/b/5xVY
Very helpful explanation. I never used mg/mmol (only used g/mol) in chemistry so I was confused at first about it, but it makes more sense now that you explained it.
Thanks Steven. I think that all of us who started off in chemistry thought in terms of g/mol. When I first started teaching this, I would have the students start off in g/mol then change to mg/mmol, then it dawned on me to just have them go straight to mg/mmol because it is the same numerical value.
Nice ! Clear, Quick just what I needed to review
Glad I could help!
saved my day thank you brad
Thanks Uploading video Sir, I was struck in millimoles your video helped me come up. Do not have words to express your kind gesture.
You are welcome. Glad I could help.
For that last step in which you solved for mEq I found a formula, just in case anyone wanted to use it. mEq=(substance in mg x valence #)/atomic weight
such an awesome doctor
thank u. ur vid is so much more helpful than my dry, boring textbook !!!!
Hi Jenny. Thanks for the nice complement. I am glad I could help. Let me know if you have any questions.-Brad
Pharmacy tech here. Had an out-of-stock situation today with a med commonly measured in mEq. Patient came to pick it up along with its paired diuretic. At the counter, during rush hour, the following ensued: "Don't have my potassium?? That's alright, I'll just grab it otc; how many mg did the doctor write it for?" Apparently it would have taken me the same amount of time to do the math as it would to call another store! I smoothly dodged his question by choosing the latter. Thanks, though, Doc!
Thanks for this! Really helped me a lot! :)
Glad I could help!
Excellent explanation
Thanks for the nice comment!
thanks, takes me back to my physics, chem and algebra days. lol
Thanks for the nice comment.
thanks for the video brad. one quick question. how much Ca2+ (in mEq) and Cl- (in mEq) are there in 20mEq of CaCl2? thanks
You would have 20mEq of Ca++ and 20meq of Cl- in 20mEq of CaCl2.
Thanks very much indeed . Much appreciated.
Sir last part cant understand sir also sir meq is said for single ion ..i.e example we cant say meq of kcl is 100 but we xan say meq of k is 100 i.e meq cant be found for molecule but only for single ion ..
thank you brad for the good video. my question is how will l prepare a 50mq Ca ion solution given a calcium carbonate compound
Hi Tonderai. You are starting with 50 mEq Ca ++ and need to change that into mg of CaC03. Since Ca++ has two charges, you will get two mEq from each millimole (mmol) of Ca++ ions. Looking up the atomic mass of CaCO3, we see that it is 100.09. This means 100.09 g/mol and 100.09 mg/mmol. Now just line everything up so that the units that you don't want cancel out and you are left with the units you want. 50 mEq(1mmol/2 mEq)(100.09 mg/1 mmol)= 2502.25 mg or 2.502 g.
Thank you Dr. Brad for this answer. I still have one question about this solution. When you line everything up, the unit of 50mEq of Ca++ can be cancelled out with the unit of 2mEq Ca++, so how can we cancel out the unit for the rest? Can I think as (100.09mg of CaCO3/ 1mmol of Ca++) so that the Ca++ unit can be cancelled out? or should it be (100.09mg of CaCO3/ 1mmol of CaCO3) ??? Thank you so much.
Hi Krystal. In the above problem the mEq units on 50 mEq are canceled out by the mEq on the 2 mEq and the mmol units in the 1 mmol/2 mEq are canceled out by the mmol units in the 100.09 mg/1mmol. It is true that you could use 100.09 mg CaCo3/1mmol of Ca++, but I think it is easier to understand if you add a ratio at the end of 1 mmol CaCo3/1mmol Ca++. This is what the problem would look like if you include all of the chemical formulas. 50 mEq Ca++(1 mmol Ca++/2 mEq Ca++)(100.09 mg CaCO3/1 mmol CaCO3)(1 mmol CaCO3/1mmol Ca++) = 2502.25 mg CaCO3. It is a little confusing if you use 100.09 mg CaCO3/1 mmol Ca++ because the atomic mass of CaC03 is 100.09 and it is easier to explain this way. I hope this helps. Let me know.
How did you get 746mg in the beginning of the equation? The only way I figured out how you got 746mg was after adding 39.1 + 35.5 = 74.6 x 10 = 746 , but where do you get the 10 to times the 74.6? thank you
That was just the weight that I chose as an example to change to mEq. I could have had a problem like, How many mEq are in 1000mg. I just chose 746 mg because it would come out to 10 mEq. I looked at the video again, and I should have added something like, "let's do a problem where we calculate how many mEq are in 746 mg of KCl. Sorry for the confusion.
Ok. Because 1 mEq is equal to 74.6 then 10 mEq is equal to 10×74.6 which is 746. Ok. Got it thank you😊
Very Nice video., and i was curious to know about conversion of mOsm.?
Hi Rajiv. Thanks for the nice comment. There is no simple conversion between concentration and mOsm because you are working with the number of particles in the solution and you have a number of factors that will affect this. Maybe I will do a video on this, but for now just google it and a lot of good info comes up.
hi Dr.Brad, I really find it difficult when it comes to computing meqs. I keep on researching and watching videos on youtube just to fully understand but I really can't cope with it. I am now reviewing for boards and I really wanna know about this one. no matter how I try, I am still getting the wrong answer this is the formula that they gave us during review days meq=mg/MW x factor. some articles says valence instead factor. what was the simplest formula in getting meqs for solving board problems? thanks for helping!
+Ayang De Los Santos Hi Ayang. I don't like those formulas. All you have to know is that a mEq is a mmol of charges. If you learn a few terms (mole, mmol, atomic mass (atomic weight), these problems are very easy. I have a mEq exercise that goes step by step. Please send me an email at brad.wojcik@gmail.com and I will send it to you. Of course anyone else who would like this material can email me also.
-Dr. Brad
+Ayang De Los Santos Hi Ayang. Here is a link to the dropbox which contains the exercises. Also, be sure to download the handout book which explains everything. Let me know if you have any questions. It is easier if you email me any specific questions. brad.wojcik@gmail.com www.dropbox.com/sh/90xs9qsjsugdy5a/AAD1pPnpo59HSU_RAYLgqekDa?dl=0
thank you Dr.brad
i have question
what is the weight of CaCl2.2H2o need to prepare a liter of solution containing
1-9mEq Ca/L
2-7mEq Cl/L
Problem 1) You have to change 9 mEq Ca++into mg. There is 147 mg/mmol and each mmol has 2 mEq because there are 2 charges on Ca ++. 9 mEq (1 mmol /2 mEq) (147. 0 mg/mmol) =661.5 mg. Problem 2) same as problem 1 except you are starting with 7 mEq. There are still 2 mEq /1 mmol because you have 2 Cl- per molecule. 7 mEq(1 mmol /2 mEq)(147.0 mg/mmol) =514.5 mg.
Brad Wojcik thank you very much
Glad to help. You can email me questions at brad.wojcik@gmail.com. It is a little easier to answer through email.
so say we had potassium sulfide, would it be 2 meq/1 mmol? Do we always choose the highest charge in the compound and ignore the lowest? Since sulfur is -2 while potassium is +1.
Hi dim. Well, let's use K2S04 as an example because K2S reacts with water to form KSH and KOH. 1 mmol of K2SO4 will yield 2 mEq of K+ because you get 2 ions from each molecule and you would get 2 mEq of SO4-2 because you get 1 ion, but 2 charges. It is easiest to think of a mEq as a mmol of charges. You get 2 mmol of charges from the K+ and 2 mmol of charges from the SO4-2. You have to look at both ions. Hope this makes sense.
okay thank you, in the video you have the 1 meq/1 mmol for KCL but wouldn't those 2 give us a total of 2 meq so shouldn't it be 2 meq/1 mmol?
Hi Dim. It is 1 mEq of K+ and 1 mEq of Cl-. You can say that you have 1 mEq of KCl or you can say that you have 1 mEq of K+ and 1 mEq of Cl-. You have to talk either about KCl all together or K+ and Cl- separately.
oh ok, what if you get a compound where one atom has a meq of 1 and the other atom has a meq of 2? Or does that not occur?
If the compound dissociates and doesn't react with water, the mEq of the cation will equal the mEq of the anion.
dr brad thank you for the good work
my question is about m mol and m osmol what is the difference ,i revise the issue in comprehensive pharmacy review but i can`t apply it to cholesterol conversion from m mol to mg/dl something is missing!!!
Hi Amr. The basic difference is that a mmol is 1/1000 mol of anything. If you have a mmol of NaCl, you have 6.022 X 10^20 molecules of NaCl and the same number of Na+ and Cl-. A mosmol is a mmol of particles. So, a mmol of NaCl would be 2 mosmol because you have a mmol of Na+ and a mmol of Cl-. Going from mmol to mg/dl would not involve any osmotic calculations. You just need the molecular weight of cholesterol and the volume of solution.
Thank you for your help
What is the cholesterol problem? I can show you how to work it.
The problem was in my approach i was trying to apply the mlosmol equation to the conversion .
In another instance i can convert it easily by recalling conversion factor of cholesterol but I want to know how to calculate it my self.
So the given was solution contains 4m mol of cholesterol , also he gave me mol wt 386 and ask for how many mg/dl in the solution
What is the volume of the solution that contains the 4 mmol?
You can download my book, Pharmacy Calculations for Pharmacy Technicians: Solving Pharmacy Calculation Problems Without All the Silly Formulas, for free at payhip.com/b/5xVY. It goes into more detail than possible on the videos and is full of practice problems and answers.
I am a failing student but i appreciate how you said sorry Avogadro haha. still trying to figure it out but you seem like a good teacher. wish me luck on my exam tomorrow i'll need it
+vacumecleaner Let me know if you have any questions. If you do, just email me at brad.wojcik@gmail.com.
Thank you kind sir nothing as of yet but I will keep it in mind thank you very much
+vacumecleaner How did you do on your exam?
Hey Dr. Brad Im not sure I got a few curve balls I didnt expect but I might have done enough to get a passing grade hopefully. I'll find out my grade next thursday
+Brad Wojcik unfortunately i failed by 3 marks! re-take is next week, i'll do you proud
thanks
good
Great video but sound is too low
HELP..
a solution of potassium phosphate contains a mixture of 164 mg pf monobasic
potassium phosphat(m.w=136)and 158 mg of dibasic posassium phosphate (m.w=174) per milliliter
a-how many milliliter of solution should be used to provide 45 mEq. of K+
b-how many millimoles of total phosphate will be represented in calculated volume
yasser martians
Hi Yasser, The monobasic his KH2PO4, so 1 mEq/mmol. The dibasic is K2HPO4, so 2 mEq/mmol. 164mg(1mmol/136mg)(1mEq/mmol)= 1.2 mEq/ml for mono. 158mg (1 mmol/174mg)(2 mEq/mmol)= 1.8 mEq/ml for dibasic. So, you have 3 mEq/ml 45 meq(1 ml/3 mEq)= 15 mL. Mono has 1.2 mmol/ml, dibasic has 0.9 mmol/ml. 2.1 mmol/ml (15 mL)= 31.5 mmol Phosphate.
Brad Wojcik
thank you
why don't you have two meq for KCL since you have a valence of two, one cation, and one anion, a valence of one was used, not two, why?
Each ion has a valence of one. You would have one mEq of potassium and one mEq of chloride, or one mEq of potassium chloride.
smart
i feel like a complete idiot in comparison with others commenting here that seem to find this clear and helpful. This video just doesnt seem either CLEAR, or specific enough...in watching it, ..i feel like there is something everyone else knows or its assumed we should know ...but i dont...I wish i could target exactly WHERE or how my confusion falls into play...i cant. i just dont feel like enough was explained. maybe im just stupid. : ( I DO undertand the ONE millimole and TWO millimole concept, but i think if we had a video based on exact examples? and ...maybe a bit more detailed explanation?? i dunno. : (
ok in going BACK over this video I figured out somethings about where i am confused, and in case someone else goes through the same stuff they can see they werent alone. The CONCEPT of mmol, mol etc, are wonderfully explained, even the atomic mass thing, but, when I was learning how to calculate for everyday practical mEq answers (vet tech stuff( I DONT remember in the ER nor in the classroom back in 99 ever having to learn/reference the periodic table to find numbers to calculate....is there a different video on here? am i missing something?! When tested, on a computer for two hours to pass the PCTB exam to get my CPhT; how will i be able to reference the PERIODIC table? Are these examples based on what I will be tested on? I cant put my finger on my confustion STILL lol! : l
Omg