Barium Sulfate is a white substance, liquid or solid, with the chemical formula being BaSO4. Barium sulfate is a radiopaque agent, which is used in order to help x-rays be more visible due to the contrast between the barium sulfate and the x-rayed parts of the body. This substance is dangerous, but due to its poor solubility ingestion will not result in the body’s absorption of the toxicity of it. Some of the dangers of ingesting Barium Sulfate however are: bloating, constipation, cramping, diarrhea, nausea/vomiting, stomach/lower abdominal pain, tightness in chest, troubled breathing, or wheezing. Barium Sulfate also reacts violently with Aluminum powders. Prolonged exposure to Barium Sulfate dust can result in baritosis, which is a form of benign pneumoconiosis. Barium Sulfate is insoluble in most substances, except for concentrated sulfuric acid.
An ample research question for this particular lab would be “How can one create five grams of Barium Sulfate?” This task explores the use of knowledge of different chemicals regarding their solubilities, concentrations and characteristics and the use of this knowledge in order to make a pre-determined five grams of Barium Sulfate. I intended to approach this problem by using my knowledge of chemicals stated above to come up with a simple, practical way of concocting five grams of Barium Sulfate.
If Barium Nitrate and Sulfuric Acid are mixed together appropriately, then we will be able to make five grams of Barium Sulfate, along with the other product. This hypothesis is clearly justifiable. If you mix 5.6 grams of Barium Nitrate with 2.1 grams of Sulfuric Acid, through the reaction types we can see that this is double replacement and should form HNO3 + BaSO4, and through some dilution calculations we can see that theoretically five grams of Barium Sulfate should be made.
–> The amounts of Barium Nitrate and Sulfuric acid. These variables are independent because they will change depending on what substances are use to make the Barium Nitrate and of what concentration.
–> The amounts of Barium Sulfate and Nitric Acid produced. These variables are dependent because they depend on the independent variables, or the Barium Nitrate and Sulfuric Acid.
–> The different materials used during the experiment are the materials used and the substances used to make the Barium Nitrate. These are controls because they do not change throughout the experiment.
–> 2 700mL beakers
–> 50mL graduated cylinder
–> 100mL graduated cylinder
–> Stirring rod
–> Digital Scale
–> Coffee Filters
–> Hot plate
–> Vacuum Flask
–> 12.5 M H2SO4
1. The true first step of this lab was to figure out how to make Barium Sulfate. In our case, we figured we would mix Barium Nitrate and Sulfuric Acid to do the trick. After subsequent calculations, we figured out that we would need 2.1g of Sulfuric Acid and 5.6g of Barium Nitrate.
2. First we placed 5.6 g of Ba(NO3)2 solid powder into the 700mL beaker
3. We then proceeded to make it into a liquid by adding approximately 100mL of water, and to better dissolve these two substances we put the solution onto a hot plate and stirred until it was sufficiently dissolved
4. Then we put 2.1g or 4mL of 12.5M H2SO4 into the 50mL graduated cylinder
5. Then we diluted the 12.5M H2SO4 to 5M by adding in 6mL of water, in order to achieve 10mL of 5M H2SO4
6. We then poured the dissolved water and Ba(NO3)2 along with the 10mL of 5M H2SO4 together in the other 700mL beaker
7. We then observed the reaction and recorded these observations. The solution was HNO3 and BaSO4, with the BaSO4 a white precipitate in the liquid HNO3.
8. To isolate the BaSO4, it needs to be filtered. We weighed the coffee filter with the digital scale, which came out to 0.5g and then placed the filter on the inside of the funnel.
9. Place the funnel over the vacuum flask so that the HNO3 will go through the funnel into the vacuum flask and the remaining substance will isolated BaSO4 after the substance from the 700mL beaker is poured into the funnel very slowly
10. Remove the coffee filter, and throw everything else out. Then let the BaSO4 on the coffee filter dry overnight
11. Then we weighed the coffee filter with the dry BaSO4, which was 4.7g, and then subtracted the weight of the coffee filter to get the true weight of our BaSO4, which was 4.2 grams.
Amounts of Reactants and Amount of BaSO4
Amount (+/- 0.5g)
5.6g in 100mL of water
Amount to Use of Each Substance
5g of BaSO4 x (1mol BaSO4/ 233.43g of BaSO4)
0.02142 mols BaSO4
0.02142 mols BaSO4 x (1mol H2SO4/ 1mol BaSO4)
0.02142 mols H2SO4
0.02142 mols BaSO4 x (1mol Ba(NO3)2/ 1mol BaSO4)
0.02142 mols Ba(NO3)2
0.02142 mols H2SO4 x (98.078g H2SO4/ 1mol H2SO4)
0.02142 mols Ba(NO3)2 x (261.336g Ba(NO3)2/1mol Ba(NO3)2
o M1 V1=M2V2
–> (12.5M H2SO4)(Xml H2SO4) = (5M H2SO4)(10mL H2SO4)
–> X = 4mL H2SO4
–> 6mL of water needed for 4mL H2SO4
(4.2g BaSO4/5g BaSO4) x 100 = 84%
[(4.2g BaSO4 – 5g BaSO4)/ 5g BaS04] x 100 = 16%
All of our equipment laid out
The vacuum flask pulling the Nitric Acid out of the Barium Sulfate
The finished, dried, Barium Sulfate on the coffee filter
Weighing the Barium Sulfate on the coffee filter
Principally, the lab was a success. We were able to come up with a perfectly good method of creating Barium Sulfate. Technically, however the lab was slightly off. Instead of coming up with the ideal five grams of Barium Sulfate, we fell 8/10ths of a gram short, which came out to a sixteen percent error. This inaccuracy suggests that something in our lab went awry. When pumping the nitric acid out of the barium sulfate, we overflowed the filter on the vacuum flask, seeing as how we didn’t take into account how thick the substance actually was. This mishap was most likely the largest contributor to our inaccuracy. Also, human error is always a factor. Inevitably, somewhere down the line we took a reading wrong or something of that nature, further skewing our results.
This lab brought up a few questions for further investigation. After finishing the lab, the question occurred to me, “if we had used an alternate method to make five grams of Barium Sulfate, could we have been more accurate, less accurate, or would our results have remained the same?”
To make a better lab, there are a couple things that could be done. First would be to take better care to observe the substances we work with much more carefully. By doing this, there is less likely of a chance of having something happen such as overflowing the funnel. Also, one could record observations better. This would make the analysis of the lab much easier, with less guesswork to do.