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Are there human-ingestible liquids that do not contain water?

Are there human-ingestible liquids that do not contain water?


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My son asked me a question that stumped me: Is there anything a human can drink that does not contain water?

It stemmed from a conversation in beverages in general where I was pointing out that they all are based on water… coffee, soda, milk, etc.

That's when he asked if there are any beverages that don't contain water. Given that nearly all of the water and even solid food I could think of contains water, I couldn't come up with anything, but now I'm curious about it to so came here to ask the experts!


Is there anything a human can drink that does not contain water?

Yes, there are a lot of liquids that do not contain water, but mostly they are not safe for human consumption.

Mercury is a liquid at room temperature. Can a person swallow it? Most assuredly. Motor oil has no water in it. It's not a satisfying beverage. Canola oil, olive oil, and many other food derived oils can be imbibed in even reasonably large amounts, but it won't do your digestive tract a big favor.

I've treated goats with propylene glycol (a liquid), parents treat their kids with mineral oil for constipation, etc. etc.

It depends on what you mean by "drink".


List 10 Types of Solids, Liquids, and Gases

Naming examples of solids, liquids, and gases is a common homework assignment because it makes you think about phase changes and the states of matter.

Key Takeaways: Examples of Solids, Liquids, and Gases

  • The three main states of matter are solid, liquid, and gas. Plasma is the fourth state of matter. Several exotic states also exist.
  • A solid has a defined shape and volume. A common example is ice.
  • A liquid has a defined volume, but can change state. An example is liquid water.
  • A gas has neither a defined shape nor volume. Water vapor is an example of a gas.

When an object is a solid, its molecules are arranged in a pattern and can’t move around much.

In a liquid, molecules are farther apart, can move around, and are not arranged in a pattern.

The movement is what makes a liquid fluid (or pourable) and take the shape of a container it is in.

The molecules in a gas are even farther apart than in a liquid and move freely with no pattern at all.

Go here to see what the molecules of substances look like as a solid, liquid, and gas.

Matter can change from one state to another when physical conditions change when energy, such as heat, is added or removed, a substance can change from a solid to a liquid, or from a liquid to a gas.

For example, peanut butter does not flow like a liquid. It acts more like a solid even though it is very soft.

However, if you use heat (i.e., add energy) to melt peanut butter, its state will change and it will flow like a liquid!

Note that not all substances can change states just by adding or removing heat—sometimes other physical changes, such as increased pressure, are needed to change the state of a substance.

Water is unique because the properties of water allow it to exist in all three states of matter!

Water is usually a liquid, but when it reaches to 32° Fahrenheit (F), it freezes into ice.

(Ice is the solid state of water.)

When water reaches 212° F, it boils. When it begins to boil, some of the water turns into steam.

(Steam is the gas state of water, and is also called water vapor.)

When steam comes into contact with cool air (which reduces energy), it can condense back into water droplets (liquid again).

Those water droplets could then freeze into (solid) ice.

Even with all of these state changes, it is important to remember that the substance stays the same—it is still water, which consists of two hydrogen atoms and one oxygen atom.

Changing states of matter are only physical changes the chemical properties of the matter stays the same regardless of its physical state!

Normally, when water reaches 32° F it begins to freeze.

As you learned in the super-cooled water experiment, water needs a nucleation site, or a spot for the first ice crystals to form.

When there isn’t one, water can reach a temperature below the freezing point without turning into ice. When that happens, the water is said to be super-cooled.

Can you think of any other ways to keep water from freezing when temperatures are below freezing?

Salt lowers the freezing point of water and is often used to melt dangerous ice off of roads and sidewalks in the winter.

To learn more about salt and ice, check out these snow and ice experiments.

To learn more about frozen science, see how to make a frozen bubble and super-cooled water that freezes in an instant!


Main Ingredients of Laundry Detergents

Powder and liquid detergents pretty much have the same ingredients, As mentioned earlier, the biggest difference is that powders often contain bleach whereas the latter does not.

Both types of detergents contain a fair amount of surfactants. These substances are responsible for lowering the surface tension between two liquids. What is surface tension? It’s a force that allows water to hold its shape and not “spread out.” These forces are broken down by the surfactant molecules, which allow the grease to be washed away. In other words, it improves the water’s ability to wet things, aka your clothes.

Physically, they have a head that is attracted to water and a tail that’s attracted to grease and dirt. When detergent molecules meet the grease, it draws in the oils while the heads remain in the water. Eventually, the attractive forces between the head and the water will lift the grease from the surface. This grease is then broken into smaller components by the detergent and washed away by water.

Surfactants aren’t the only thing that’s in laundry detergents. Look at the ingredients label and you’ll see that they contain various other substances as well. For instance, you’ll often find optical brighteners, chemicals that will brighten your clothes, and enzymes, which help to dissolve and break down the gunk. Many products also contain perfume, which gives your laundry that “clean and fresh” scent.


6 Tips for Cutting Back on Plastic

Totally avoiding plastic is almost impossible, but it's possible to reduce your exposure to concerning chemicals found in these products.

  1. Eat fresh food. The more processed your food is, the more it may have come into contact with materials that could potentially leach concerning chemicals, says Muncke.
  2. Don’t buy into “bioplastic” hype. Green or biodegradable plastic sounds great, but so far it doesn’t live up to the hype, Wagner says. Most data indicate that these products aren’t as biodegradable as their marketing would imply, he says. Plus, this latest study showed that these products (such as biobased, biodegradable PLA) can have high rates of toxicity, he says.
  3. Don’t use plastics that we know are problematic. But don’t assume that all other products are inherently safe,either. The American Academy of Pediatrics has previously noted that the recycling codes “3,” “6,” and “7” indicate the presence of phthalates, styrene, and bisphenols, respectively—so you may want to avoid using containers that have those numbers in the recycling symbol on the bottom. Wagner adds that “3” and “7” also indicate PVC and PUR plastics, respectively, which his study found contained the most toxicity. But products made from other types of plastic contained toxic chemicals, too, which means that reducing your plastic use overall is probably the best way to avoid exposure.
  4. Don’t store your food in plastic. Food containers can contain chemicals that leach into food. This is especially true for foods that are greasy or fatty, according to Muncke, and foods that are highly acidic or alkaline, according to Vandenberg. Opt for inert stainless steel, glass, or ceramic containers.
  5. Don’t heat up plastic. Heating up plastics can increase the rate through which chemicals leach out, so try to avoid putting them in the microwave or dishwasher. Even leaving plastic containers out in a hot car could increase the release of concerning chemicals, says Vandenberg.
  6. Vote with your wallet. Try to buy products that aren’t packaged in plastic in the first place, says Vandenberg. “We need to make manufacturers aware that there is a problem,” she says. “There are products that could provide the benefits we need to make the food chain safer.”

Correction: The original article published on September 17, 2019, incorrectly stated that phthalates are used in PVC pipe. This reference has been removed, and the article has been updated to reflect that phthalates are used in imitation leather and some plastic shower curtains.


Endosymbiosis

An American researcher, Lynn Margulis, proposed in 1966 the hypothesis of endosymbiosis, which may explain the advent of the first eukaryote. According to Margulis, there were two successful invasions of an early anaerobic (one not requiring oxygen) prokaryote, by smaller independent prokaryotes. One of these prokaryote invaders entered the larger prokaryote probably for protection and easy access to nutrients, decided to stay, and began to reproduce independently inside the host cell. Rather than try to evict the invader, the two cells developed a mutually beneficial relationship. The invading cell is thought to be the modern-day mitochondria. A second invasion of similar style, but this time by a photosynthetic bacterium, eventually became a chloroplast. Interesting evidence supports this hypothesis. First, both mitochondria and chloroplasts contain their own DNA, which is separate and different from the rest of the cell. Second, the arrangement of their DNA is circular, a characteristic of prokaryote cells. Finally, both reproduce independently of the rest of the cell.


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Solidifying Science: Why Can Certain Fruits Ruin Your Gelatin Dessert?

Introduction
Have you ever noticed that if you're making a gelatin dessert, such as JELL-O, it's not recommended to use certain fruits, like pineapple? Why is this? These fruits may prevent the gelatin from solidifying. In this activity you'll get to determine if certain enzymes in some fruits can keep the gelatin from gelling&mdashand whether there's a way to still include these fruits without ruining your gelatin dessert!

Background
If you like making gelatin for dessert, the box often recommends not adding certain kinds of fruit, including pineapple, kiwi, mango, ginger root, papaya, figs or guava. People have a hard time getting the gelatin to solidify when they add these fruits. Gelatin is made from collagen, which is a structural protein found in all animals. Collagen is found in many parts of the body and helps give animals their structure, or shape. Gelatin, which is a mixture of collagen proteins, solidifies when you cook it because its proteins form tangled mesh pockets that trap the water and other ingredients. After the gelatin cools, the proteins remained tangled. This results in your wiggly-jiggly gelatin dessert.

The fruits listed above contain proteases, which are enzymes. Enzymes help make certain chemical reactions happen. Proteases specifically act like a pair of scissors, helping reactions take place that cut other proteins up. In this activity you'll explore whether these protease enzymes are preventing the gelatin from solidifying (by cutting the gelatin's collagen proteins into such small pieces that they are no longer able to tangle together and create a semisolid structure). To do this you'll inactivate these proteases by using heat.

Materials
&bull One cup of one of the following types of fruit, which should contain proteases: figs, ginger root, guava, kiwi fruit, mango, papaya or pineapple. Make sure the fruit is fresh.
&bull Knife
&bull Cutting board
&bull Measuring cup
&bull Water
&bull Stove top
&bull Fruit/vegetable steamer (optional)
&bull Pot, large enough to hold three cups of liquid
&bull Clock
&bull Three plastic cups or drinking glasses, each at least 12 ounces in size
&bull Tape and permanent marker or pen (optional)
&bull Gelatin mix (such as JELL-O), enough to make three cups of gelatin
&bull Three utensils for stirring, such as spoons or forks
&bull Refrigerator

Preparation
&bull You may want to have an adult help cut up the fruit and use the stove.
&bull Carefully cut up one cup of the fresh fruit.
&bull Cook one half cup of the cut fruit. Do this by either steaming or boiling the fruit (with about one quarter cup of water) for five minutes. How does the cooked fruit look?
&bull Add the raw fruit to one plastic cup or drinking glass and the cooked fruit to a different plastic cup. If it's difficult to tell the difference between the raw and cooked fruit by looking at them, you may want to label the cups (with tape and a permanent marker or pen).

Procedure
&bull Make the gelatin dessert according to the package instructions. You will want to prepare at least three cups of liquid gelatin.
&bull Add one cup of gelatin liquid to each of the cups with fruit, and add the third cup portion to an empty cup. You should now have three cups with gelatin liquid in them.
&bull Thoroughly stir the contents of each cup. Use a different, clean utensil to stir each cup.
&bull Refrigerate all three cups, noting the time at which you put them inside the refrigerator.
&bull An hour after you put the cups in the refrigerator, check the consistency of the gelatin in each cup. Continue checking their consistency once an hour until the gelatin in the cup without fruit solidifies. (This will probably take about four hours.) In which condition(s) does the gelatin set? In which condition(s) does the gelatin remain a liquid? Are there any in-between cases?
&bull What do your results tell you about how the proteases affect the gelatin solidification process and how heat affects the proteases?
&bull Extra: In this activity you explored fruits that contain proteases, but many fruits do not contain proteases. You could repeat this activity using apples, blueberries, oranges, raspberries and strawberries&mdashall of which do not have proteases. How well does the gelatin solidify when using fruits that do not contain proteases?
&bull Extra: Meat tenderizer contains some of the same proteases that are found in the fruits explored in this activity. Try making a gelatin dessert with meat tenderizer (by dissolving one teaspoon [tsp.] of meat tenderizer in one tsp. of water and adding this to the one cup of gelatin liquid). Can gelatin solidify when it is made with meat tenderizer? If a solution of meat tenderizer is heated, is the enzyme deactivated?
&bull Extra: You used heat in this activity to inactivate the proteases in fruit, but other temperatures and conditions may inactivate the proteases as well. Does freezing the fruit inactivate the proteases? Do other processes, such as drying or canning, inactivate the proteases?

Observations and results
Did the cup with the raw fruit remain a liquid? Did the cups with the cooked fruit and no fruit added solidify like normal?

Normally the collagen proteins in gelatin form a tangled mesh that traps water and other ingredients in it, giving the gelatin its semisolid form when it cools. Proteases can cut up the proteins so that the gelatin cannot solidify. There are several different kinds of proteases in the fruits recommended for this activity, and using any of these fresh fruits should result in gelatin that does not solidify well, if at all. Heating the fruit (through boiling or steaming), however, should inactivate the proteases, and the resulting gelatin mixture should solidify like normal (or nearly normal&mdashif the fruit was hot when the gelatin was added, the solidified gelatin may have been slightly less firm than that in the cup without fruit). The proteases bromelain and papain (which come from pineapples and papayas, respectively) are often used in meat tenderizers. There are several other fruit proteases, however, such as actinidin (from kiwi fruit), ficin (figs) and zingibain (ginger).

Cleanup
You may enjoy a tasty fruit and gelatin dessert. Be sure to store it in the refrigerator until it is consumed.

More to explore
What Exactly Is JELL-O Made from? , from Discovery Communications, LLC
Science of fruit jellies , from The Naked Scientists: Kitchen Science
Enzymes Make the World Go 'Round , from Rader's Chem4Kids.com
Which Fruits Can Ruin Your Gelatin Dessert? , from Science Buddies


This activity brought to you in partnership with Science Buddies


7. Conclusions, Open Issues, and Future Directions

What can we conclude from this recounting of some of the more prominent recent attempts to construct models of scientific explanation? What important issues remain open and what are the most promising directions for future work? Of course, any effort at stock-taking will reflect a particular point of view, but with this caveat in mind, several observations seem plausible, even if not completely uncontroversial.

7.1 The Role of Causation

One issue concerns the role of causal information in scientific explanation. All of the traditional models considered above attempt to capture causal explanations, although some attempt to capture non-causal explanations as well. It is a natural thought (endorsed by many) that many of the difficulties faced by the models described above derive at least in part from their reliance on inadequate treatments of causation. [15] The problems of explanatory asymmetries and explanatory irrelevance described in Section 2.5 seem to show that the holding of a law between C and E is not sufficient for C to cause E hence not a sufficient condition for C to figure in an explanation of E. If the argument of section 3.3 is correct, a fundamental problem with the SR model is that statistical relevance information is insufficient to fully capture causal information in the sense that different causal structures can be consistent with the same information about statistical relevance relationships. Similarly, the CM model faces the difficulty that information about causal processes and interactions is also insufficient to fully capture causal relevance relations and that there is a range of cases in which causal relationships hold between C and E (and hence in which C figures in an explanation of E) although there is no connecting causal process between C and E. Finally, a fundamental problem with unificationist models is that the content of our causal judgments does not seem to fall out of our efforts at unification, at least when unification is understood along the lines advocated by Kitcher. For example, as discussed above, considerations having to do with unification do not by themselves explain why it is appropriate to explain effects in terms of their causes rather than vice-versa.

These observations suggest that insofar as we are interested in causal forms of scientific explanation progress may require more attention to the notion of causation and a more thorough-going integration of discussions of explanation with the burgeoning literature on causation, both within and outside of philosophy. [16] A number of steps in this direction have been taken. (cf. Woodward 2003).

Does this mean that a focus on causation should entirely replace the project of developing models of explanation or that philosophers should stop talking about explanation and instead talk just about causation? Despite the apparent centrality of causation to many explanations, it is arguable that completely subsuming the latter into the former loses connections with some important issues. For one thing, causal claims themselves seem to vary greatly in the extent to which they are explanatorily deep or illuminating. Causal claims found in Newtonian mechanics seem deeper or more satisfying from the point of view of explanation than causal claims of &ldquothe rock broke the window&rdquo variety. It is usually supposed that such differences are connected to other features&mdashfor example to how general, stable, coherent with background knowledge a causal claim is. However, notions like &ldquogenerality&rdquo are vague and not all forms of generality seem to be connected to explanatory goodness. So even if one focuses only on causal explanation, there remains the important project of trying to understand better what sorts of distinctions among causal claims matter for goodness in explanation. To the extent this is so, the kinds of concerns that have animated traditional treatments of explanation don&rsquot seem to be entirely subsumable into standard accounts of causation, which have tended to focus largely on the project of distinguishing causal from non-causal relationships rather than on the features that make causal relationships &ldquogood&rdquo for purposes of explanation.

Another important question has to do with whether there are forms of why-explanation that are non-causal. If so, how important are these are in science and what is their structure? Hempel seems to have thought of causal explanations simply as those DN explanations that appeal to causal laws which he regarded as a proper subset of all laws. Thus on his view, causal and non-causal explanations share a common structure. Kitcher&rsquos unificationist model was also intended to apply to both causal and non-causal explanations such as unifying argument patterns in linguistics. More recently, there has been a great upsurge of interest in whether there are non-causal forms of explanation, with some claiming they are ubiquitous in science (e.g., Lange 2017, Reutlinger & Saatsi 2018). If there are such explanations, this raises the issue of what distinguishes them from causal explanations and whether there is some overarching theory that subsumes both causal and non-causal explanations.

7.2 A Single Model of Explanation?

As noted above, one way in which the attempt to develop a single general model of explanation might fail is that we might conclude that there are causal and non-causal forms of explanation that have little in common. But even putting this possibility aside, another possibility is that explanation differs across different areas of science in a way that precludes the development of a single, general model. It is, after all, uncontroversial that explanatory practice&mdashwhat is accepted as an explanation, how explanatory goals interact with others, what sort of explanatory information is thought to be achievable, discoverable, testable etc.&mdashvaries in significant ways across different disciplines. Nonetheless, all of the models of explanation surveyed above are &ldquouniversalist&rdquo in aspiration&mdashthey claim that a single, &ldquoone size&rdquo model of explanation fits all areas of inquiry in so far as these have a legitimate claim to explain. Although the extreme position that explanation in biology or history has nothing interesting in common with explanation in physics seems unappealing (and in any case has attracted little support), it seems reasonable to expect that more effort will be devoted in the future to developing models of explanation that are more sensitive to disciplinary differences. Ideally, such models would reveal commonalities across disciplines but they should also enable us to see why explanatory practice varies as it does across different disciplines and the significance of such variation. For example, as noted above, biologists, in contrast to physicists, often describe their explanatory goals as the discovery of mechanisms rather than the discovery of laws. Although it is conceivable that this difference is purely terminological, it is also worth exploring the possibility that there is a distinctive story to be told about what a mechanism is, as this notion is understood by biologists, and how information about mechanisms contributes to explanation.

A closely related point is that at least some of the models described above impose requirements on explanation that may be satisfiable in some domains of inquiry but are either unachievable (in any practically interesting sense) in other domains or, to the extent that they may be achievable, bear no discernible relationship to generally accepted goals of inquiry in those domains. For example, we noted above that many scientists and philosophers hold that there are few if any laws to be discovered in biology and the social and behavioral sciences. If so, models of explanation that assign a central role to laws may not be very illuminating regarding how explanation works in these disciplines. As another example, even if we suppose that the partition into objectively homogeneous reference classes recommended by the SR model is an achievable goal in connection with certain quantum mechanical phenomena, it may be that (as suggested above) it is simply not a goal that can be achieved in a non-trivial way in economics and sociology, disciplines in which causal inference from statistics also figures prominently. In such disciplines, it may be that additional statistically relevant partitions of any population or subpopulation of interest will virtually always be possible, so that the activity of finding such partitions is limited only by the costs of gathering additional information. A similar assessment may hold for most applications of the CM model to the social sciences.


Salty Science: Is There Iodine in Your Salt?

Introduction
Have you ever noticed if the salt you're using says it's "iodized"? Iodine is a micronutrient, which means we need it in small quantities to be healthy. Because iodine is relatively rare in many people's normal diets, it's added to table salt. Then when people salt their food, such as tasty turkey, stuffing and mashed potatoes, they're also getting iodine. In this science activity you'll use some kitchen-friendly chemistry to investigate which types of salt have iodine and which don't. Then when you sit down to your Thanksgiving dinner, you can know whether to also give thanks that you're helping combat iodine deficiency.

Background
Micronutrients, such as iodine, are types of nutrients that people need in small amounts. Iodine is important for a person's thyroid to function normally. (The thyroid is a gland in the neck that makes key hormones.) It is found in small amounts in other foods, including saltwater fish, seaweed, shellfish, yogurt, milk, eggs, cheese and a handful of other edibles. If a person doesn't consume enough iodine, they can become iodine deficient. The lack of this micronutrient can cause different medical problems (usually due to hypothyroidism caused by a thyroid that does not make enough hormones). These conditions include goiter (a visible swelling of the thyroid) as well as serious birth defects. In fact, iodine deficiency is the most common preventable cause of mental retardation.

Iodine (in the form of iodide) is added to table salt to help prevent iodine deficiency. Since the 1980s there have been efforts to have universal salt iodization. This has been an affordable and effective way to combat iodine deficiency around the world, but not all salt contains iodine, however. You'll investigate whether different salts have iodine by mixing them with laundry starch, which forms a blue-purple&ndashcolored chemical with iodine. (Vinegar and hydrogen peroxide are added to the salt solution to help this chemical reaction take place.)

Materials
&bull Disposable plastic cups that are 10 ounces in size or larger. (Alternatively, you could use smaller cups and scale down the activity.)
&bull Distilled water
&bull Measuring cups
&bull Measuring spoons
&bull Laundry starch solution, also called liquid starch (Alternatively, you could make a suitable starch solution by dissolving one cup of starch-based biodegradable packing peanuts in two cups of water.)
&bull Iodine antiseptic solution (optional) (Use either an iodine tincture or povidone-iodine solution, found in the first aid section of grocery stores and drugstores. If the iodine doesn't come with a dropper, you'll also need a medicine dropper.)
&bull Disposable plastic spoons
&bull At least three different types of salt to test&mdashfor example, plain (noniodized) table salt, iodized table salt, pickling salt, rock salt, kosher salt, "lite" salt and sea salt (If you aren't using the iodine antiseptic solution, include iodized table salt.)
&bull 3 percent hydrogen peroxide
&bull White vinegar

Preparation
&bull If you are using an iodine antiseptic solution, you can prepare a positive control cup so you know what the reaction between iodine and starch should look like. To do this, pour one half cup of distilled water into a disposable cup, add one half teaspoon (tsp.) of laundry starch solution and then add five drops of the iodine antiseptic solution. Be careful when handling the iodine because it can stain.
&bull Stir well with a disposable plastic spoon. What happens to the liquid when the iodine is added?

Procedure
&bull Pick one of the types of salt you want to test and measure out four tablespoons (tbsp.) into a clean, plastic, disposable cup. Add one cup of distilled water to the salt and stir well for about a minute with a clean, disposable plastic spoon. You do not need all of the salt to dissolve.
&bull Then add one tbsp. of white vinegar, one tbsp. of hydrogen peroxide and one half tsp. of starch solution. What do you think the purpose of the starch is?
&bull Stir the salt solution well with the disposable plastic spoon and then let the solution stand for a few minutes. What happens to the solution after you stir it? Does it become a blue-purple color?
&bull Repeat this process using the other, different types of salt you want to test. For each type, be sure to use a different, clean disposable cup and spoon. Do any of the other salt solutions become a blue-purple color?
&bull Based on your results, which salts do you think contain iodine (in the form of iodide) and which do not? Do your results agree with the labeling on the salt packages, which often say whether the salt contains iodide or not?
&bull Extra: Try this activity with even more different types of salts. For some ideas, see the Materials list above. Which types of salt contain iodine and which do not? Do your results agree with their labeling?
&bull Extra: In this activity you added vinegar because it is an acid and helps the chemical reaction take place. Try testing the iodized salt solution again but this time leave out the vinegar. Does the reaction still take place, turning the solution a blue-purple color? If the reaction occurred, did it take a longer amount of time to happen?
&bull Extra: Temperature often affects chemical reactions. You could try this activity again, but test an iodized salt solution at different temperatures (by heating or cooling the distilled water). How does changing the temperature of the solution change how the color-changing reaction takes place?

Observations and results
Did the iodized table salt solution change to a blue-purple color when you mixed in the starch? Did the "lite" table salt similarly change color whereas most of the other salt types did not?

In this activity you should have seen that the iodized table salt and the "lite" table salt solutions both changed to a blue-purple color (as did the iodine antiseptic solution, if you used it). This indicates that iodide is present in these types of salts. You likely saw no color change for the solutions made using the noniodized salt, rock salt, kosher salt or sea salt because these varieties do not typically contain iodide.

The starch solution was used in this activity because it forms a blue-purple&ndashcolored chemical when combined with iodine. Because the solution&rsquos original pH needs to be changed for this chemical reaction to effectively take place, vinegar (an acid) is also added. Hydrogen peroxide is used to turn the salt's iodide into iodine, which the starch reacts with.

Cleanup
Be sure to thoroughly wash any measuring spoons or other utensils that came into contact with the solutions made in this science activity. You can dispose of the solutions by pouring them down the drain.

More to explore
Micronutrient Information Center: Iodine, from the Linus Pauling Institute, Oregon State University
Micronutrient Deficiencies: Iodine Deficiency Disorders, from the World Health Organization
Testing for Iodide in Table Salt ( pdf ), from Stephen W. Wright, Journal of Chemical Education
Determining Iodide Content of Salt, from Science Buddies

This activity brought to you in partnership with Science Buddies


Watch the video: Regina Dugan at D11 2013 (October 2022).