hhamodat wrote:Oh I forgot to mention that our hot plate is not a hot plate stirrer! so i guess it only heats not stirs... but is it possible to add a stir bar in it? If so where can I get a stir bar?
Some hot plates have a stirrer and some do not. If it cannot stir, adding a stir bar won't help...
If it does both, it will have two knobs. One for heat and one for stirring speed.
ok so is it final that i only should use 15 ml for each tablet? Because my mom's friend is wondering If i still need more HCl- should I say that I have enough or would more be better?I did do the experiment that zzzzdoc told me and i know it won't make a difference but should i ask for more? Or will that make it less safe?
I talked with my science teacher and she said that if i use a spoon at the same speed then it should be accurate and no need for magnetic stirrer. Plus our hot plate only heats!
Thanks for the procedure Chris and zzzzdoc! I read it and it's kind of like what i'm planning to do already- but i guess i'm sticking with spoons not the Aparatus!
If you dilute 2 molar HCl to 0.1 molar concentration, then you will be reducing the concentration by a factor of 20 (2/0.1 = 20), and therefore you will increase the total volume by a factor of 20. So, if you start with 175 mL, how much solution would you have after the dilution?
ok! So i have 125 ml of HCl. And it's 2 molar to change it to 0,1 molar i have to add 20 times more water. Which would mean pouring the HCl to 2500 ml of water. Am I correct? I thought that i just need to pour it on to 175 ml of water! Oh no! That means I wrote the wrong thing on my proposal! So what exactly is the correct answer? I;m confused!
That is close - your final volume would be 20 times your initial volume, so if you start with 125 mL of HCl, you would dilute that to a total volume of 2500 mL. That's the same as saying that you would mix your 125 mL with an additional 2375 mL of water to achieve a total volume of 2500 mL.
Let's see if we can clear up the confusion. In your proposal, I think you were assuming that you would mix 175 mL of 2 molar HCl with another 175 mL of water to produce 350 mL of 1.0 molar HCl - or something close that, right? In some of the previous posts, I explained why I think you should use a maximum concentration of 0.1 molar, and not 1 molar. That is why these dilutions (in this post) are different from the ones in your proposal. I don't think that will be a big problem - scientists change their procedures all the time as they figure out how to best complete their experiments.
Part of the confusion might stem from the amount of 2.0 molar HCl that you currently have. In an early post, you wrote that you have 175 mL, and more recently you have been writing that you have 125 mL. Is it 125 mL?
I'm sorry about changing the number a couple of times. It's actually 125 ml of 2 molar HCl. See I'm too scared to open the bag and actually read the amount since I'm afraid something is going to happen! So at first I estimated 175 ml of HCl, however I then looked through it and it said 125 ml so yeah- i'm sorry about that.
Ok so I am going to pour 125 ml of HCl to 2375 ml of water which will dilute it to 0.1 molar and have 2500 ml of solution. So that means for each trial i use 125 ml of HCl! Ok i'm so happy now, I understand and I have plenty of solution! Well then, i can tell my mom's friend I don't need anymore! THANK YOU SOOOOO MUCH EVERYONE! ESPECIALLY YOU CHRIS!
I'm sorry about changing the number a couple of times. It's actually 125 ml of 2 molar HCl. See I'm too scared to open the bag and actually read the amount since I'm afraid something is going to happen! So at first I estimated 175 ml of HCl, however I then looked through it and it said 125 ml so yeah- i'm sorry about that.
Ok so I am going to pour 125 ml of HCl to 2375 ml of water which will dilute it to 0.1 molar and have 2500 ml of solution. So that means for each trial i use 125 ml of HCl! Ok i'm so happy now, I understand and I have plenty of solution! Well then, i can tell my mom's friend I don't need anymore! THANK YOU SOOOOO MUCH EVERYONE! ESPECIALLY YOU CHRIS!
Don't be too scared, just be careful and wear the right gloves/googles/apron etc.
Hi i'm starting my project tomorrow but I have a problem! I just noticed i don't have all the pills. I have ibuprofen, acetaminophen, asprin but the naproxen sodium is not an over the counter pill! i called pharamcies and went to a couple and they said i needed a percription. I explained that it's a science project but they still won't let me! So do you know any other pain relievers that are over the counter? please reply asap! I'm trying to finish the project tomorrow! Also, what things should I add in my background information? and when I finish it i'm kinda not exactly sure of the scientific answer and why it dissolved first? Can you please help? thanks
I found a list of what are called non-steroidal anti-inflammatory drugs, which tend to be available over-the-counter, here: http://en.wikipedia.org/wiki/NSAIDs. (You have to scroll down a ways for the list, and then click on each to see brand names and such.) I don't know if you'll actually be able to find a pharmacy that carries any of the ones you don't already have. Definitely go to a drug store and not just a pharmacy within a larger grocery store, though, because they'll have a wider selection.
That said, I think a comparison between aspirin, acetominaphin and ibuprofen is fine--those are the drugs people most commonly take, so those are the ones they'll be interested in seeing how fast they dissolve. Perhaps you could try different versions of those three? For example, does Tylenol dissolve faster or slower than generic acetominaphin?
What you put in your background is up to you--I would suggest that you include information about why things dissolve, why we would care that pain relievers dissolve faster or slower, and something about the pain relievers themselves.
I suggest doing some research, if you haven't already, on why things dissolve faster or slower. It's fine to not know for sure exactly why something dissolved before something else, though--there are several possible explanations for why that might be (including the fillers we described earlier!), and it's fine to just discuss each of them.
Hi,
Naproxen can be bought over the counter under the brand name Aleve. But as Melissa said I am sure that comparing spirin, acetominaphin and ibuprofen would be sufficient.
-Caroline
carolinethorn wrote:Hi,
Naproxen can be bought over the counter under the brand name Aleve. But as Melissa said I am sure that comparing spirin, acetominaphin and ibuprofen would be sufficient.
-Caroline
Apparently, only in the US. All other countries it is a controlled medication. I think the student is in Canada.
I also think the three easy to obtain pills are fine.
I didn't know that Naproxen was prescription only in Canada. Interesting.
Just in case, look for Anaprox, or Apo-Napro-Na, or Novo-Naprox Sodium, or Nu-Naprox, or Synflex in the pain reliever aisle of your pharmacy. All of them are Naproxen based.
I agree that Aspirin, Acetominophen, and Ibuprofen should be enough. Make sure not to use enteric coated Aspirin. Just normal, run of the mill, aspirin.
Almost all of the NSAIDs on that Wikipedia list are prescription only.
zzzzdoc wrote:Almost all of the NSAIDs on that Wikipedia list are prescription only.
Ooops. Sorry about that. For some reason I was thinking NSAIDs were all over-the-counter. And I didn't know that Aleve was prescription-only in Canada, either!
Yes i'm in canada and unfortuneatly any brand of Naproxen Sodium is prescription only. But my dad's friend is a family doctor and he might be able to bring it for me!! So i'm happy about that! Ok i want to do my project at home with my mom's supervision, but we were wondering what to do with the hydrochloric acid! After each test I need to get rid of the acid and clean everything but i can't pour the acid down the sink cuz that will burn it and ruin the ocean! my science teacher said that we're supposed to put chemicals in a designated container or jar! except after that what do we do? I'm really frightened to do this project except everything is due on feb 19th and i'm presenting it that day so i don't have much time left! as for the background information i'm finished it all but does it matter what language it is? Cuz it's in englsih but the rest is all in french. But the background information is just an extra in a booklet on the desk! Thanks for all your help!!!
hhamodat wrote:Yes i'm in canada and unfortuneatly any brand of Naproxen Sodium is prescription only. But my dad's friend is a family doctor and he might be able to bring it for me!! So i'm happy about that! Ok i want to do my project at home with my mom's supervision, but we were wondering what to do with the hydrochloric acid! After each test I need to get rid of the acid and clean everything but i can't pour the acid down the sink cuz that will burn it and ruin the ocean! my science teacher said that we're supposed to put chemicals in a designated container or jar! except after that what do we do? I'm really frightened to do this project except everything is due on feb 19th and i'm presenting it that day so i don't have much time left! as for the background information i'm finished it all but does it matter what language it is? Cuz it's in englsih but the rest is all in french. But the background information is just an extra in a booklet on the desk! Thanks for all your help!!!
Please, please... don't test naproxen sodium! Since you cannot get it without a perscription, I think this will look very odd to the judges that you got this, and may get you and the Dr. in trouble. It isn't really important anyway, you have at least 3 types of pills to study, correct?
I thought you were doing these tests at school in a hood? If so, the teacher should have an acid waste container that you can use. The school will have a contract with a company to remove the waste. You cannot do this at home...
I got an idea! I should've thought of it before but i hope it's not too late! I was thinking of comparing generic vs brand.
Only 3 types: Acetaminophen, Ibuprofen, Aspirin
Example: Acetaminophen x 2: Tylenol and genric
3 tests and 3 tests
= 6 tests
125ml per test x 18 (3 types 6 tests each) = 2250 ml of solution
2500- 2250 ml = 250 ml of solution to dispose
So 3 tablets of Tylenol 3 tablets of Genric
So 6 tablets per type, 6 tests per type, 750 ml of solution per type.
Would it work out if I do that? I can test which type of pain reliever dissolves the fastest but then if the genric or brand have a difference between their dissolution rates!
I'm going to ask my science teacher if I can do it in her lab!
I think you might be better off doing more repetitions of each experiment, using a smaller volume of acid. Say 50ml at most. Safer, and more than enough to dissolve the pills. That way, I think you should be able to do 10 tests of each pill. A little more work, but better statistics. (50ml x 8 repetitions, x 3pills x 2 types(generic and name brand) = 2400 ml).
No way of knowing the answer, but a number of name brand manufacturers produce the pills for the generic companies, under a different label's name. So, the generic acetominophen may, in fact, be real Tylenol. You would then be comparing apples to apples (Tylenol to Tylenol), not oranges, but it is still a valid comparison.
zzzzdoc wrote:I think you might be better off doing more repetitions of each experiment, using a smaller volume of acid. Say 50ml at most. Safer, and more than enough to dissolve the pills. That way, I think you should be able to do 10 tests of each pill. A little more work, but better statistics. (50ml x 8 repetitions, x 3pills x 2 types(generic and name brand) = 2400 ml).
No way of knowing the answer, but a number of name brand manufacturers produce the pills for the generic companies, under a different label's name. So, the generic acetominophen may, in fact, be real Tylenol. You would then be comparing apples to apples (Tylenol to Tylenol), not oranges, but it is still a valid comparison.
I agree that more tests per sample is a better idea. However, if you look at a pill like advil, and the generic, they clearly have different coatings, so you could test that and be sure that you were not testing identical pills.
Bottom line- do whatever is interesting to you. zzzdoc is right that 3 tests per pill may be too little, so maybe increase that since it will help your data analysis to have good statistics. However, whether you do what you proposed, what zzzzdoc proposed, or some mixture I think this is going to be a great project.
Louise wrote:
Bottom line- do whatever is interesting to you. zzzdoc is right that 3 tests per pill may be too little, so maybe increase that since it will help your data analysis to have good statistics. However, whether you do what you proposed, what zzzzdoc proposed, or some mixture I think this is going to be a great project.
Louise
ok i'm really happy because i'm done my experiment! I did at the school lab with a teacher and it took forever except my results were kind of messed up. Ok so the fastest dissolving was Tylenol, then Ibuprofen, Acetaminophen, then Advil. The Aspirin however and the AAS did not dissolve. Well I waited a really long time and stirred, and the blue coating came off but nothing else changed. For everything else it took 40 seconds and starting breaking up. So we just stopped after like 15 minutes and decided that it won't dissolve. But i then discovered that it says on it "delayed release tablets" and a person who did it before me had to wait 30 minutes or so. But I think it's ok because I do know which one is the slowest even though i don't know the exact time. Plus for the generic vs brand, brand is better because Tylenol was better than Acetaminophen. For Aspirin (brand) it at least got the blue coating off so it did kind of dissolve faster than AAS, which was white and never changed at all.
So i'm done and I'm ready to put it on the board and everything but I have a couple of questions. So I calculated it and for me, for safety issues, my solution was only 5% of HCl which is extremely low and not that acidic. How much HCl is in our stomach? Was i tooo off?? Plus I was wondering if you could help me with finding the differences between Molars, pH, concentration, and acidity? I'm starting to get confused about them.
Is there anything else I should add? I did the project by putting 8 beakers, at the same time and doing it like that so it was pretty accurate! I tried my best but it did take more than i thought it would. I came home from school at 6:00!!
I also have another thing. I did 8 tests per generic and brand, so for each type of pain reliever it was 16 tests. So like Acetaminophen= 16 tests... and so on. So i did the averages and all.. so i think the results are reliable. Also i did 50 ml per test!
What about the scientific reason? I was comparing the coatings and the non-active ingredients and noticed it made a huge difference.
(fastest dissolving to slowest)
1.) Tylenol- Caplet, hardly any filler
2.) Ibuprofen- coated, a bit of filler
3.) Acetaminophen- tablet hardly any filler
4.) Advil- tablet a lot of filler
5.) Aspirin- coated a lot of filler
6.) AAS- coated a bit less filler than Aspirin
Is that enough reasoning? I was going to say about chemicals but I didn't understand that so I didn't!! What else should i say for scientific explanation??
Nice job, Hayam. You also learned that science can be rewarding, but no one ever said it was easy.
Before I forget. What is AAS? It's not a standard abbreviation in medicine in this country. Is it the delayed release aspirin?
Delayed release tablets (also known as enteric coated tablets) are designed to dissolve in the beginning of your small intestine, not your stomach. The environment is not especially acidic there (it might actually even be alkaline, I would need to check). That can explain the delayed dissolution of those tablets.
I'll need for some of the chemistry experts to go over the molar concentrations with you. I haven't thought about those in many years. T
To answer some of your questions:
The amount (in volume) of acid in your stomach varies minute by minute, depending on what you eat, nervous and hormonal influences, etc.. It can be very little, to about 150ml (not counting food contents on top of that.) Anything greater than that amount of gastric fluid is an abnormal state (even that amount is markedly abnormal, a condition known as gastroparesis).
Gastric pH varies during the day. Food provides buffer and the pH goes up. Then the gastric cells release acid and the pH goes down. Over 90% of the time in volunteer studies, the gastric pH is less than 4.0. I don't think it ever is less than 1.0. Usually it's in the 2.0 - 4.0 range, I believe.
I'm confused as to what you are defining as "hardly any filler." Do you mean that the weight of the tablet is only slightly greater than the weight of the active drug? I doubt that is true. Typically, the inactive ingredients are about 99% of the total weight. Or do you mean that after dissolving, there is very little residual white powder remaining (the pill is very soluble in chemical terms)?
It's good that you got in multiple trials of your experiment. Your data will be that much more conclusive because of that.
50 ml was quite generous for the volumes. Clearly if the pill was going to dissolve, it would dissolve in that volume.
Out of curiosity, what are the mean times for dissolution of the particular pills?
Nice work. Now start analyzing your results, make some good looking graphs of the data, and an eye-catching chart. You'll do great on your project.
First of all, I think that Aspirin is not the actual name for the generic because Aspirin is made of acetylsalicylic acid so that was the generic brand. And on my bottle of it is says AAS wich is the abreviation of it. So yeah, it's acetylaslicylic acid!
So the aspirin didn't dissolve because it wasn't supposed to? It gets dissolved in our intestine and then the medicine goes down to our body?
So I guess my project is pretty reasonable, because if you are supposed to have about 150 ml of HCl in our stomach and mine had 125, that's pretty close! I'm glad about that. Our stomach is the pH of 2-4 so that's equal to 0,1 molar I suppose?
For hardly any filler, I meant that the non-active ingredients listed weren't that much way less listed than others and that there was about no powder left. It was almost clear!
The results were as the following:
1.) Tylenol with the average of 484,375 seconds
2.) Ibuprofen with the average of 562,5 seconds
3.) Acetaminophen with the average of 658,75 seconds
4.) Advil with the average of 949,5seconds
5.) Aspirin not sure!
6.) AAS not sure!
I have 50 ml of solution left with me which is enough to do another test, so my teacher suggested I do it for the Aspirin or AAS to see around how much it would take it to dissolve. So which one should I do? if I do AAS i know that aspirin would be less than the results or vise versa.
What are some things that judges or my teacher might ask me? I'm trying to get ready for it because I'm starting my board! Thanks!!
Hi Hayam,
I'm glad to hear that everything worked out well with your experiment. Congrats!
A 0.1 molar solution of HCl would have a pH of about 1. If someone asked you how to calculate this value, you could tell them:
pH = - log10(H+) (this is the definition of pH)
H+ is the hydrogen ion concentration, which we assume is the same as the molar concentration of HCl.
log10(H+) is the logarithm of the H+ concentration (0.1 in this case).
In math jargon: 10^(-1) = 0.1, so log10(0.1) = -1
There are other factors that can affect pH of water, such as naturally occurring carbonates and other solutes, but you probably don't need to worry about that.
First of all, I think that Aspirin is not the actual name for the generic because Aspirin is made of acetylsalicylic acid so that was the generic brand. And on my bottle of it is says AAS wich is the abreviation of it. So yeah, it's acetylaslicylic acid!
So the aspirin didn't dissolve because it wasn't supposed to? It gets dissolved in our intestine and then the medicine goes down to our body?
So I guess my project is pretty reasonable, because if you are supposed to have about 150 ml of HCl in our stomach and mine had 125, that's pretty close! I'm glad about that. Our stomach is the pH of 2-4 so that's equal to 0,1 molar I suppose?
For hardly any filler, I meant that the non-active ingredients listed weren't that much way less listed than others and that there was about no powder left. It was almost clear!
I have 50 ml of solution left with me which is enough to do another test, so my teacher suggested I do it for the Aspirin or AAS to see around how much it would take it to dissolve. So which one should I do? if I do AAS i know that aspirin would be less than the results or vise versa.
What are some things that judges or my teacher might ask me? I'm trying to get ready for it because I'm starting my board! Thanks!!
The name "aspirin" is composed of a- (from the acetyl group) -spir- (from the plant genus Spiraea) and -in (a common ending for drugs at the time). It has also been stated that the name originated by another means. "As" referring to AcetylSalicylic and "pir" in reference to one of the scientists who was able to isolate it in crystalline form, Raffaele Piria. Finally "in" because it was a common ending for drugs at the time.
On March 6, 1899 Bayer registered it as a trademark. However, the German company lost the right to use the trademark in many countries as the Allies seized and resold its foreign assets after World War I. The right to use "Aspirin" in the United States (along with all other Bayer trademarks) was purchased from the U.S. government by Sterling Drug in 1918. Even before the patent for the drug expired in 1917, Bayer had been unable to stop competitors from copying the formula and using the name elsewhere, and so, with a flooded market, the public was unable to recognize "Aspirin" as coming from only one manufacturer. Sterling was subsequently unable to prevent "Aspirin" from being ruled a genericized trademark in a U.S. federal court in 1921. Sterling was ultimately acquired by Bayer in 1994, but this did not restore the U.S. trademark. Other countries (such as Canada and many countries in Europe) still consider "Aspirin" a protected trademark.
So you learn something every day. I've never seen the AAS, and ASS abbreviations for it, as a physician practicing in the United States.
You are somewhat misinterpreting my comments regarding the volume in the human stomach. Usually it is empty. But anywhere from 0 - 125 or 150ml of residual volume can be considered a normal state. I would consider 125ml to be the upper limits of normal for gastric volume, which means normal. So you chose a good volume. I just want you to understand that a person taking an aspirin could conceivably have a perfectly empty stomach, which would also be normal. What small amounts of acid are then released would act to dissolve the pill.
Please tell us the exact ingredients on one of the bottles. Both active and inactive ingredients, and the amounts of them if they are listed. I still believe that the active ingredient would be a small minority of the weight of the entire pill. 325mg of aspirin, for example, is a tiny weight. A pill will weigh several grams (or several thousand mg) I would assume. I think what your experiment showed was that both the inactive and active ingredients were very soluble in your acid solution, in a relatively short period of time. That would result in the clear solution after the pill dissolves.
Personally, I don't think it matters which of the Aspirin or ASA tablets you use for the final experiment. You would be only guessing as to which is less soluble than the other. You could hedge your bets and dissolve each separately in 25ml of solution, and see which takes longer. But if they both don't dissolve in that small a volume, you don't prove anything, and it really is a more stringent test than the 50ml normal test you used. But, always a good idea to do what your teacher asks.
Your data has a nice range of values. Pretty interesting. I wouldn't have guessed the order in which they finished.
zzzzdoc wrote:
Please tell us the exact ingredients on one of the bottles. Both active and inactive ingredients, and the amounts of them if they are listed. I still believe that the active ingredient would be a small minority of the weight of the entire pill. 325mg of aspirin, for example, is a tiny weight. A pill will weigh several grams (or several thousand mg) I would assume. I think what your experiment showed was that both the inactive and active ingredients were very soluble in your acid solution, in a relatively short period of time. That would result in the clear solution after the pill dissolves.
[snip]
.
This question actually came up in the very beginning of the project. The bottles don't list the inactive ingredients' masses, so there were two suggestions proposed. Call the company and ask for the info, which was apparently problematic for US made drugs and their Canadian hotlines. Or weigh the pills and subtract out the mass of the active ingredient. For common balances, I suggested weighing many pills at once, and calculating the average mass for improved accuracy. I think this would be a good test to do if there is extra time. If I were a judge, I would ask about this.
yes I think I should do that too, but I don't know where I can get a weight scale that measures something so light. I don't think he have any at school. Even if I put like 10, I still don't think it can weigh it. But I'll see what I can do.
And it doesn't say but i think that the active is just acetaminophen!
I really need help about the title! What is a good catchy title for my project? I can't think of anything because the question is too long and not that fun so i need something that's good!! Thanks!!
so i guess it only heats not stirs... but is it possible to add a stir bar in it? If so where can I get a stir bar?
/-/https/www.sciencebuddies.org/cdn/Files/21464/5/sb-logo.png){kind=logo}
/-/https/www.sciencebuddies.org/cdn/Files/21464/5/sb-logo.png){kind=logo}
