HELP ME ASAP!!

[hhamodat]

hi,

I'm doing a project on what type of pain reliever dissolves the fastest. I'm going to test if acetminophen, ibuprofen, naproxen sodium or aspirin dissolves the fastest in gastric fluid. To subsitute the fluid in our stomachs i'm using hydrochloric acid. And i'm going to use a magnetic stirrer and then time how long it took for it to dissolve. For each type of anaglesic i'm going to repeat it 5 times then find the average.

I have a hard time trying to find the materials however. I can't find hydrochloric acid or a mangetic stirrer. I need about 3 L of the acid and it's really hard to find. So i am wondering if you can help me find it.

My science teacher suggested that if i don't use HCl then i should use vinegar because that's acidic as well. But HCl is in our stomach which makes the results more reliable. When our stomach digests our foods, it produces Hydrochloric acid. So if i use this it will be more reliable. Since there's a big chance i can't find it- i'm also wondering if vinegar would give me the same results. Because vinegar is not in our stomachs it's just acidic. So pleaseeeeeeee help me asap because my science proposal is due Dec.12 and i have to make sure i have all the materials.

So- will vinegar give me the same results?

[ghariman]

Hi there,

You may want to try posting your question in the Life, Earth and Social Science's forum (the other forum in the Ask an Expert Forum):
https://www.sciencebuddies.org/mentorin ... um.php?f=3
as there they discuss more Biology type of questions.

If you can wait a while, then often a volunteer here who has better Chemistry background should pop in and help you out. This person is who I am talking about:
https://www.sciencebuddies.org/mentorin ... ile&u=1819

But if it is urgent try the other Forum first then come back here again later.

[carolinethorn]

Hi,

Concentrated hydrochloric acid is very very corrosive and can cause nasty chemical burns and has to be stored correctly so it is a restricted substance, ie. not just anyone can buy it so you might need to ask help from your teacher or consider a different material.

If you are going to use HcL then you should have a safety plan and safety equipment for working with such a toxic and large quantity of the acid. Perhaps you can scale it down - 3L is a large amount to have especially if it is an open container. You also need to think about how concentrated the acid will need to be for the experiment - stomach acid HCl is very dilute compared to the concentration you can buy from a chemical supplier so you would not need to buy that much of it.

I found this supplier where your teacher could purchase it with you
http://www.sciencekit.com/category.asp_Q_c_E_1024308
I have no idea if they are reputable though.
Academic labs usually buy from the supplier Sigma Aldrich but I am not sure if a teacher can do this or if they have dilute solutions for sale.

Magnetic stirrers can be quite expensive. The site i linked about for the acid has one that is not too bad for price ($89.95 - called the squid, but its for a fairly small beaker size). There are a couple of used lab supplier websites where you might be able to get one for cheaper (google used lab equipment). - some of them are like Ebay where is it an auction.
There are possible alternatives you could come up with for providing continuous motion or mixing to simulate stomach conditions - you might have to be more creative - which is not a bad thing as this project can be quite common so I expect judges would be interested to see new ideas. I was thinking that a putting your "stomach contents" in a clear ziploc bag inside a kitchen aid mixer might work - you would want to test this with a bag of water first to see if it bursts or tangles and what speed to use.

I think suggesting vinegar as an alternative is a reasonable idea. A beaker of HCL is only one kind of possible models of a stomach and there are plenty of others out there. It would be safer for you (espcially if you decide to try alternatives to a magnetic stirrer). I cannot say if the results would be the same - you would need to compare the results between HCl and vinegar (which is mostly ethanoic acid, CH3COOH) to tell or find a paper where someone else has done that experiment. A judge will not mark you down for choosing a safer method if you describe why you did it that way and what the effects of the choice might be.

Best of luck,
-Caroline

[deleted-2131]

Science Kit is a respected distributor of middle and high school science equipment, so if your teacher orders from them you can be assured of that the product you are getting is of sufficient quality for your project.

Stomach acid is approximately equivalent to a 1 molar solution of HCl, so you'll want to make sure that you either buy a quantity of HCl in the appropriate concentration or dilute the HCl you do buy (acid to water, never water to acid!)

This poject should only be conducted if you are wearing acid gloves, a face shield, a chemical apron, and are working in a fume hood. If you don't know what these things are, ask your science teacher. HCl is a dangerous and volatile chemical that should not be used without proper safety measures.

For further information, please consult an MSDS for HCl, like the one found here: http://flinnsci.com/Documents/MSDS/H/HyAcSo.pdf

[hhamodat]

Hi,

I did not come up with this idea but there are about 4 people who have done it before me. I am basing my project on their's because it worked and they seemed to have it all done correctly. Here are the websites of the people who have done this project before:
http://www.selah.k12.wa.us/SOAR/SciProj ... elleS.html
http://www.selah.k12.wa.us/SOAR/SciProj ... coleS.html
http://www.selah.k12.wa.us/SOAR/SciProj ... tlynS.html
http://www.selah.k12.wa.us/SOAR/SciProj ... essaW.html

As for the concetration, one of the projects done before have said to make sure the fluid has a pH of 4.0 mixture. I believe that that is the same as the pH of our stomach. Plus i think if i heat the acid to around 37 degrees- that will make it the same as our stomach.

Do i just need an acidic fluid and that will give me the results or does it have to be hydrochloric acid? The website you gave me is very helpful but it seems very expensive. I don't think it's possible for me to obtain any more then the 175 ml that i have right now. Oh, and how should i store that? It hasn't spilled it's in a cabnet and is covered very well. I'm kind of afraid to use this chemical without being in a lab.

As for the "stomach contents" do you think i should make myself bring it out? It's kind of disgusting- and i don't think i can get around 2L of it.

So in conclusion- should i just use vinegar and explain that i couldn't use the hydrochloric acid? or should i mix vinegar with the hydrochloric acid i have right now? Plus, the magnetic stirrer i'll try to ask my teacher if she can get it for me. The hydrochloric acid i have is not that concetrated because my friend's dad said that it would be way more safer and he would feel more comfortable giving me less concetrated acid.

I need to know what i'm going to do in these 3 days!! If you have a look at the one's done before- you will notice that they all used hydrochloric acid but didn't say they had worked in a lab.

Thanks for all your help![/list]

[hhamodat]

Hi,

I re-read what you have posted to me earlier and i understand what you mean. So if i get a small quantity of HCl and add on water it will make it dilute? What is a normal pH of HCl? If it already is as acidic as our stomach and if I add water it will make it less concetrated. I am very confused. A girl who had done this project before added water onto the HCl and said to measure the pH and make sure it's 4. I need a solution that is easy to get and not that expensive and something that i can handle. It's too late for me too change my project but i think that maybe i can find a way to get something similare to Gastric Fluid. I need help!

Thanks!

hhamodat

[carolinethorn]

Hi,

When I said "stomach contents" i meant that whatever you choose to SIMULATE the contents of the stomach, either HCl or vinegar. I was not suggesting that you use your own stomach contents.

The pH or the solution and the concentration are related but different. pH describes how acidic it is (which is a measure of how many hydorgen ions are in the solution), but concentration is how many molecules are in the solution. You are correct, if you add more water to the solution it will become less concentrated and it will effect the pH. You could test the pH before and after dilution to see how much it changes. The second link of previous experments that you posted had a detailed decription of both the pH and the concentration of acid she used. This is much better than the first link where they did not state how concentrated the acid was. Although they did not say this I expect that they did work in a lab (link 1 has pictures inside a lab) and that they or their teacher diluted the acid in a fume hood.

What is the concentration of the acid that you have? Perhaps your friend's Dad can help supervise you doing the experiment to make sure you do not put yourself in danger. I think you need some in person help to make sure that you are safe.

SInce you are so worried about the timing, write your proposal to give both ideas - hat you will use the HCl acid if you can provide the appropriate safety conditions but that if you cannot that you will substitute a less toxic acid such as vinegar. List both types of acids in your materials and put a note that the vinegar is if you are unable to use the HCl.

Best of luck,
Caroline

[hhamodat]

I wrote up my proposal without any mention of the concetration or the pH level of the HCl. I added in about the vinegar but it just occured to me that vinegar is not that acidic so what can i do to bring it up to the pH of 4? For my hypothesis i don't really have anything to base it on. I think that the acetaminophen will dissolve the fastest because it says on the bottle that it reacts quickly for relief but i need more of an educated hypothesis. As for the magnetic stirrer, i think i should just use a blender- it might give me the same results. I don't know the concentration of the HCl that i have because i got it from my friend's dad's friend. I have tried reaching a lab but i might be too young. I'm in grade 7 and i don't know anyone who can supervise me.
Can you explain to me what a molar is because someone has previously told me that the stomach fluid is equal to 1 molar of HCl. That makes HCl more acidic?
For safety issus i think i do need a lab however so i'll try my best.

Thanks for all your help.

hhamodat

[hhamodat]

I just found out that the HCl that i have is 2 molars. So that means it's more acidic than the stomach fluid. If i add water on, that will decrease the pH level and the concentration which will give me more solution and less acidity. How much will i have to dissolve each tablet into? Would 50 ml be enough? Because if i have around 175 ml and i dilute it will that give me about 2 L of solution that is about the same as Gastric Fluid? On my proposal, what should i say the pH of the HCl or vinegar be? And what would be the concentration? If i were to dilute it how much water would be added. Or how much water will the HCl be poured into?

Thanks so much.

Hayam

[deleted-71447]

Hayam,
If your current solution is 2 molar, then you have plenty of HCl. pH is a logarithmic scale, such that every increase of 1 pH unit (for example, raising pH from 1 to 2) corresponds to a 10-fold dilution. A HCl solution with a pH of 2 is 0.01 molar, pH of 3 is 0.001 molar, and pH of 4 is a 0.0001 molar solution. So, to dilute your acid to a pH of 4, you could dilute it by a factor of 2/0.0001 = 20,000. That's a lot of acid.

Obviously, a 2 molar HCl solution is pretty strong, and you should heed all the previously mentioned warnings about working with strong acids.

Good luck,
Chris

[hhamodat]

So in ml or L, how much HCl would i have if i dilute it? And about how much water would i have to add?

[deleted-71447]

If you diluted 175 mL (0.175 L) of 2 molar acid to 0.0001 molar, you would have 2M / 0.0001M * 0.175L = 3,500 L. I don't think you want that much.

You can do a similar calculation to figure out how much of your 2 molar solution you would need to start with to make 2 L of 0.0001 molar HCl. I get something like 0.1 mL, which is about 1 drop.

All these calculations are helpful, but you really will need a way to measure the pH to verify that your final solution has the desired pH.

[deleted-71576]

Hi there,

If you can wait a while, then often a volunteer here who has better Chemistry background should pop in and help you out. This person is who I am talking about:
https://www.sciencebuddies.org/mentorin ... ile&u=1819

So, I'm looking up the link to see who George is referring to and, Whoa, that's me.

Let's see if we can help Chris. And also, you really should post this in the Life Sciences Section. It's their area of interest / expertise. And I'll leave it up to the chemists to do the dilution calculations. Haven't thought about those in years.

A couple of points:

1.) Your stomach pH varies considerably. There are many people who take H2 blockers or Proton-Pump Inhibitors to raise their gastric pH, to avoid ulcers. Yet, the medicines you are studying do dissolve in their stomachs.

2.) You stomach is not usually full of liquid. In fact, most of the time it's pretty empty. So large quantities of acid solution should not be required to dissolve the drugs you are studying.

3.) You really should have some way of measuring the pH of your acid solution, as Chris G has said.

4.) One quick search I did showed a pH of Vinegar at 2.8, and gastric contents at 1.0. Another showed Vinegar at 4.0 and gastric acid at 2-4. The truth is that 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

That being said, you really don't need to pick an extremely acid environment like a pH of 1.0. Pick anything in the 2-4 range and keep it constant for all of your trials. If Vinegar is consistently in that range, I don't see why it couldn't provide a good experiment. It its pH is more alkaline than that, HCl would be more proper.

[hhamodat]

Since our stomach is not full of liquid, i shouldn't add that much and wouldn't need to put the pills into that much fluid. So around how much liquid should each pill be dissolved in? is 25 ml enough? that way i would all need about 500 ml of acid. Which can be easily brought if i dilute my HCl to have a pH of 4. And change the 2 molar to a 1 molar? I am trying to find a mentor who can help me and supervise me in a lab and maybe they could help step by step. As for the proposal, what should i base my hypothesis on and what exactly should i include in my procedure? I'll try to find a way to measure the pH of the HCl i have now so then i know how much i need to dilute. Thanks,

Hayam

[hhamodat]

would my project be considered biochemistry or chemistry?

[MelissaB]

I would think that 25 mL would be enough, but you might want to do a few trial runs with it to make sure the pain relievers will dissolve in that amount of acid. I think it's a good idea to find a mentor who can help you with this, because acid can be very dangerous if you don't know what you're doing.

You can base your hypothesis on personal experience, the personal experience of others, on the claims of the pain reliever companies themselves, or on previous research, depending what you have access to. Which one do you think will dissolve fastest? Do any claim to dissolve faster than the others?

In your procedure, you want to include a step-by-step description of what to do with enough detail that someone could look at your notebook and repeat your experiment by following your procedure.

I would consider the project to be biochemistry, but you might double-check with your teacher to be sure.

[deleted-2131]

I would call your project chemistry, but the category really depends on the guidelines your fair provides you, as these tend to vary from fair to fair.

The issue here isn't so much pH as it is molarity. Don't worry about the pH as much as getting the molarity adjusted.

According to BIOLOGY, (Campbell and Reece, 6th ed.) a well-respected biological sciences text, gastric fluids are equivalent to about a 1 molar solution of HCl.

A 1 molar solution is a solution that has one mole of the solute dissolved in 1 liter of water. So, since you have 175 ml of 2 molar HCl, this means that you have about 0.35 moles of HCl in your solution, or about 12.78 grams of HCl in your solution. So, to dilute the solution to a 1 molar concentration, you need to add another 175 ml of water to the acid, giving you a total of 350 mL acid. (See http://www.mpcfaculty.net/mark_bishop/m ... utions.htm for some examples of how I got this answer.)

I would suggest using 10 mL of acid per pill.

You can base your hypothesis on the package information from the different medications (e.g. "I think that Tylenol will dissolve the fastest because its package says that it is the fastest dissolving pain reliever.")

[hhamodat]

Thank you sooo much for your help! I get everything now. MelissaB told me to dissolve each pill into 25 ml and Terik Daly told me to dissolve each pill into 10 ml so i'm going to do 20 ml. And each type of pill 5 times. so i'm going to need about 400 ml of fluid which i have after i dilute it. For my hypothesis, i found some information on Acetaminophen so i can base my hypothesis on that So i know what i'm going to do and i just need to focus on getting a mentor and a lab! Thanks to everyone!

Hayam

[deleted-71576]

Since our stomach is not full of liquid, i shouldn't add that much and wouldn't need to put the pills into that much fluid. So around how much liquid should each pill be dissolved in? is 25 ml enough? that way i would all need about 500 ml of acid.

Certainly 100ml should be sufficient. When patients are on tube feedings, the prevailing wisdom is to keep gastric residual volume (the amount of liquid in the stomach) to less than 150ml. So I would certainly set a ceiling of no more than 150ml. And I don't think any of those substances would form a supersaturated solution that couldn't support any more dissolution, so I don't think that huge volumes are needed. 25ml is a very small volume. I'm not sure how well those painkillers dissolve under normal conditions, much less the large amount of filler substances in the pills. You can easily find undissolved pills in patients colons (I see this all the time.)

So I guess, my answer is that my hunch is that you need a bit larger volume than you are thinking about, but I'm really not sure. I'd start with a test run with one of the tablets, and keep adding small, measured amounts of water until it totally dissolves. That should be the minimum amount you use.

[hhamodat]

So there's still a problem. I just have barely enough HCl if I use 25 ml for each pill to dissolve in. But if that's not enough i need about 100 ml for each pill which would mean i need about 2 L of solution if i'm planning to to 5 trials. So this way i still need more HCl that i can dilute to equal 2L. I hope i can figure out a way to get more HCl. And so far i have no luck in finding a mentor or a lab.

Thanks

Hayam

[Louise]

would my project be considered biochemistry or chemistry?

I would consider this a chemistry project. While you are testing something related to biology, your actual experiment is purely chemical.

I am a chemist, and I wanted to emphasize some safety issues. Someone already mentioned that you should have the right safety equipment (gloves, googles, apron, etc.), but you should also be aware of the protocols for diluting acids. You always add the acid to the water, and not the water to the acid. If you add water to acid, you can cause the strong acid to bounce and splash. If you add the acid, any splashes will be mostly water. Oh, and do not use hot water when mixing. Use room temperature water.

See: http://jchemed.chem.wisc.edu/jcesoft/CC ... /MOVIE.HTM

{I couldn't get the movie to work, but the written info is good}

You should work with someone trained in lab work (like your science teacher) and have access to running water. If you do get splashed with acid, how quickly you can get water on the area to wash it off is critical for preventing acid burns. {Generally, chemicals on the skin at treated by 10-15 minutes of running water- in addition to any needed medical treatment.}

I think zzzzdoc's suggestion of doing a test run and trying different volumes of acid is a great idea, and could be one of your tests/hypothesis.

One other point that zzzzdoc brings up is the idea of filler. Look at your pills- usually they have 100-500 mg of painkiller. Weigh your tablets... you'll find that they weigh more than that. The inactive ingredients list tells you what the filler is. This is another thing you could choose to study- does the amount of filler influence how fast the pill dissolves? Does the type of filler have an effect?

Here is some more safety information for HCl:
http://www.jtbaker.com/msds/englishhtml/h3886.htm

It is a good idea to look over this with your teacher. It does sound very scary, but it basically lists every possible bad thing and how to fix it, so it is useful to have if something goes wrong.

Louise

[hhamodat]

I need to know exactly how much simulated gastric fluid i need. I only have around 125 ml ( i don't exactly because i was too afraid to open the bag and read how much ml it is). One person did a project kind of the same as mine but she only said to have 100 ml of HCl but add pepsin and amalyze. I'm not sure what those are and i don't know where to get them but i will ask my teacher if she can help me get the materials. If not- i have to go back to the vinegar idea. Except how much molars is vinegar compared to our stomach? I can so much of vinegar and that should give me around the same results but i need to know the pH or the molar of the vinegar. If i use vinegar- i won't need a lab or a mentor because vinegar is not dangerous. So what is the molar of vinegar compared to our stomach and if i'm using HCl how much should i dissolve each pill into? And about how many trials? would three be enough? That way i wouldn't need that much HCl!

Thanks!!

Hayam

[deleted-71576]

Pepsin and amylase are enzymes that break down organic compounds in the stomach.

From wikipedia, here are the definitions of pepsin and amylase:

Pepsin is a digestive protease released by the chief cells in the stomach that functions to degrade food proteins into peptides.

Amylase is the name given to enzymes that break down starch. They are classified as saccharidases, enzymes that cleave polysaccharide(s).

If you look up the chemical formulas of the substances you are considering studying, they certainly aren't starches. On the other hand, the majority of the pill is composed of filler substances. I'm not sure what those are. You could get into the situation of the acetominophen dissolving perfectly, but the filler staying insoluble. From a pharmaceutical perspective, this is perfectly fine - the medicine gets into your body. For the purposes of your experiment, this will make you think that the medicine is insoluble in that volume, even though it is.

I would again go back to the suggestion I made earlier. Take a acetominophen tablet and crush it up. Add small measured amounts of water (or vinegar) and see how little fluid it takes to dissolve. This will give you an idea of how much volume you need, and perhaps if vinegar will work.

You are asking for the answers before performing the experiment. This isn't how science works. One learns as an experiment is going on, and further modifies future experiments based on the lessons learned. This is the fun, and challenge of science.

Also, have you considered calling up the pharmaceutical companies who manufacture these drugs, and asking them if they know how much volume it will take and at what pH they dissolve? You never know if you are connected with a chemist who could be incredibly helpful to you. My son made a similar phone call to Coca Cola for his science fair experiment, and, even though it took a lot of time, they did fully answer his technical question. You might try their web site to e-mail them too. Also provides a nice reference for your bibliography.

[hhamodat]

Hi,

Is a filler kind of like a coat? This might make a difference because 2 of the medicine i have are uncoated but the Aspirin is coated. On the ingredients, it doesn't mention anything about filler.

If I do the test of the Acetaminophen- why should i chrush it? Because when human's take a pill they swallow it not chew it so it will make it easier to dissolve if it is crushed. The Acetoaminophen is generic, and it's uncoated. So why should i crust it? And how you're saying to keep on adding more vinegar, do you mean test it with vinegar with so many trials excpet each one have a different amount of fluid and see which one gives the fastest dissolution rate?

^Thanks

Hayam

[Louise]

Hi,

Is a filler kind of like a coat? This might make a difference because 2 of the medicine i have are uncoated but the Aspirin is coated. On the ingredients, it doesn't mention anything about filler.

If I do the test of the Acetaminophen- why should i chrush it? Because when human's take a pill they swallow it not chew it so it will make it easier to dissolve if it is crushed. The Acetoaminophen is generic, and it's uncoated. So why should i crust it? And how you're saying to keep on adding more vinegar, do you mean test it with vinegar with so many trials excpet each one have a different amount of fluid and see which one gives the fastest dissolution rate?

^Thanks

Hayam

Read my answer to you above... I talk about filler, and how to identify it. You can tell how much filler there is by weighing the tablets. The filler must be listed as an "inactive ingredient". It may not be on the bottle, but it must be listed somewhere- on the box or the package insert.

As I mentioned before, the filler may effect the rate of dissolving. (This may be on purpose- some drugs try to dissolve slowly so you get an effect for a long time). The coating may also have an effect[1]. This is something you need to test or control for. So either test how different coatings and pill shapes effect the dissolving rate or only test one type of coating.

[1] some aspirins that are coated even say it is gentler on your stomach, since it dissolves more slowly.

I think you should go back and carefully read all the advice given in this thread. Many different variations have been suggested... there are enough ideas here for 10 science fair projects. You need to decide what you are most interested in testing. No one is going to design the experiment step by step for you, so you need to make some choices about what you want to do.

zzzdoc only suggested crushing the tablet to test the volume as a simple test. A crushed pill can be dissolved quickly. Then, you can see exactly how much liquid you need. This is a prelimanary test you do before you try your real experiments. [This is what zzzdoc means when he is talking about "how science works". Try some simple experiments to get an approximate idea of how the real experiment works] When you know that volume (10 mL, 200 mL, whatever), then you would test all your tablets in whatever way you think is best. I agree, uncrushed is probably best, as it is closest to what happens in the body.
Louise

[deleted-71576]

For fun, I tried this test at home with Ibuprofen and warm water. The results were actually pretty impressive.

Your turn to do the work on your experiment, Hayam. Take a pill, dissolve it in a small known quantity of water (or vinegar) and see what happens, and how quickly it happens. I think you will be happy with the results.

I also looked on the labels. At least for the generic Ibuprofen and Acetominophen I had around the house, they only listed the active ingredient, not the inactive percentage. I wonder if the FDA changed the labelling requirements. That being said, I'm sure they can be found easily online. For example, the inactive ingredients of Tylenol can be found at their website:

http://www.tylenol.com/product_detail.j ... ubpreg#Top

They don't say what quantity are in each pill, but as Louise said, they can be determined by weighing and subtraction. Unfortunately, you will need an analytical balance to weigh that accurately (the most accurate scale I have at home, which is better than most, weighs to 0.1g accuracy. You will need a scale that can measure to at worst 0.01g accuracy to get those results.) On the other hand, I'm sure the company would give that information to you if you contact them.

[Louise]

[snip]
Hayam,

They don't say what quantity are in each pill, but as Louise said, they can be determined by weighing and subtraction. Unfortunately, you will need an analytical balance to weigh that accurately (the most accurate scale I have at home, which is better than most, weighs to 0.1g accuracy. You will need a scale that can measure to at worst 0.01g accuracy to get those results.) On the other hand, I'm sure the company would give that information to you if you contact them.

I have two bottles of painkiller- one has the info on the bottle, the other doesn't. I'm pretty sure it is listed on the consumer insert or the box tho.

Getting the info from the company is probably the best bet, but if they won't tell you (and they may consider this info a trade secret), then you should do the weighing.

Now, what I would do for the mass issue (if you cannot find an analytical balance) is weigh 10 or 50 or whatever numbers of pills that you can get an accurate mass. Then, figure out the filler per pill. You may want to do this with differing large numbers of pills, and average the results.

Louise

[hhamodat]

zzzzdoc,

I tried what you told me and i had terrible results. First of all, was i supposed to stir it? I don't have a magnetic stirrer so i thought that i can try with a spoon. So i poured about 30 ml of vinegar into a glass cup. Then i got a tablet of acetaminophen and crushed into powder then i put it in the vinegar and started timing while i stirred. My hand smelled like vinegar, my hands hurt, over 11 minutes passed- and nothing happened. It didn't dissolve! So i just stopped it. I also tried 125 ml of vinegar but didn't stir and nothing happened to that one either! Now i'm pretty sure I need a magnetic stirrer.

I might be able to get HCl- my mom's friend said she'll try. So that's a positive thing. As for the mass of the filler- i'm going to try calling the companies but i don't have that much hope. If that doesn't work i'll just take Louise's advise.

Please tell me if i did something wrong in my *pre-test*.

Thanks a bunch,

Hayam

[hhamodat]

I just read the labels of the the 3 different pain reliever bottles that i have and they all list the non-medical ingredients- that's the same as inactive right? There's a lot of non-medical ingredients so I'm guessing that it has a big effect on the dissolution rate.

[hhamodat]

i was just checking the website of Aspirin and it says that the expected time for it to dissolve is 2-4 HOURS! I thought way less- well that means I should have waited and not given up. Is that the average time of pills to dissolve? This project might take longer then i expected.

Most websites do say the inactive ingredients just not the weight of it.
http://www.aspirinforprevention.ca/FAQs ... tion.asp#8
http://www.rxlist.com/cgi/generic/ibup.htm

Well i hope i have some positive things coming up becaue everything has been a downfall so far. oh well! i'll have my hopes up!

Hayam