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59

There are different angles this question can be answered: Chemical point of view: A full analysis of a totally unknown mixture is painful and extremely costly. It is always helpful to know how many components you are looking for; what types etc. In this case, it is not enough to analyse the elemental composition or some pure elements, but Coke contains a ...

50

The starch forms a loosely bonded network that traps water vapor and air into a foamy mass, which expands rapidly as it heats up. Starch is made of glucose polymers (amylopectin is one of them, shown here): Some of the chains are branched, some are linear, but they all have $\ce{-OH}$ groups which can form hydrogen bonds with each other. Let's follow some ...

48

The "fishy" odor that you're familiar with is brought about by a whole bunch of compounds, and not any single one. Then again, if we were to narrow this down a bit, we could say that simple nitrogen compounds are the main culprits. But suppose we want to blame only a single compound for the delightfully pungent odor of rotting fish, and we couldn't be ...

37

There are two ways to efficiently make an aerosol product: Use a gas that liquifies under the pressure inside the can. For example, butane lighters. Nitrogen is one of the "fixed gases", meaning it's a gas under most conditions (but take a look at the temperatures and pressures needed for liquid nitrogen—it's not going to ever be found in consumer products)....

35

There are 2 cases, both related to the acid-base reactions. Both are also partial reasons why so many fish recipes use lemon juice. Fish, especially sea fish, naturally contain trimethylamine-N-oxide $\ce{(CH3)3N-O}$ that, after death, gets enzymatically reduced to trimethylamine $\ce{(CH3)3N}$, the source of ammonia-like fish odour. Trimethylamine N-...

32

It is not proven that "sugar makes your body acidic"! Your body's pH is very tightly regulated by the body's internal systems; it is also different in different parts of the body - the stomach is acidic (1.0-2.5), the intestine are mildly basic (jejunem 7-9) terminal ileum 7.5 reference here. Blood pH is 7.35, and any deviation from this is indicative of ...

28

Sugar is made by repeatedly boiling and cooling cane syrup (or sugar beet syrup). After each cooling, the solution becomes supersaturated with respect to sucrose, causing sucrose to crystallize out of the "mother liquor" (the industrial term for the liquid solution from which crystals form). These crystals of "raw" sugar are heavily processed (washed in ...

26

Technically, even simple water can cause rust, so nothing surprising here. However, spoilage of milk most probably produced a lot of organic acids (lactic acid and similar) which can speed up any corrosion process. Lactic fermentation is a natural fermentation process in milk, when bacteria start converting the sugar content of milk to lactic acid. It is not ...

26

The main substances that cause the yellowish color of the milk are carotenoids [1]. The main carotene involved is the beta-carotene coming from the feed that cows eat. Some studies have been carried on and it has been noticed that the milk with a more yellow tinge was collected during late spring and early summer when carotene levels are at a maximum [2] ...

25

According to Nitrous oxide, carbon dioxide, and their mixtures as propellants, Proc. Chem. Specialties Mtrs. Assoc., June 1950, page 45, William Strobach, CO2 and N2O are both suitable because they each have some solubility in both the aqueous and oil phase of the cream emulsion. 85% N2O / 15% CO2 has the most preferable taste, with too much CO2 being too ...

24

With modern technology it would be a relatively straightforward process to determine all of the ingredients in Coca Cola. It would require time and money, but very doable. My guess is that companies that compete with Coca Cola, like Pepsi, know exactly all of the ingredients in Coke. This is part of the process known as "reverse engineering" and is done ...

24

No salt will be pure NaCl. Each will have some degree of other elements. The fact that the salt isn't white confirms there are other elements present. See Analysis of Gourmet Salts for the Presence of Heavy Metals which investigates 14 salts including two Himalayan salts. See especially "Table 3. Comparison of toxic elements in Table Salt". A "...

22

If you don't mind, I'll start with a more colloquial and hopfully not to lengthy explanation: Precious metals, such gold, do not corrode under "household conditions", others, such as iron or aluminium do. Rusting of iron is a typical example. Here, the corroded surface often is very porous and the corrosion carries on until the whole piece of metal is ...

21

The raisin has nucleation sites on it that allow bubbles of $\ce{CO2}$ to form. The raisin is light enough to be lifted by the bubbles as they push their way to the surface. As the bubbles are released into the atmosphere, the raisin once again sinks until more bubbles form on it. This will continue until the soda water has lost the majority of its dissolved ...

21

You got me curious, so I poked around a bit on this. First there is insoluble and then there is insoluble. The Wikipedia article on capsaicin lists its solubility as $\pu{0.0013 g}/\pu{100 mL}$ which is $13$ parts per million. So capsaicin is "relatively insoluble", but not wholly so. Second the Wikipedia article also points out that capsaicin itself is ...

21

Do not do it !! ( putting acidic, or rather any juice to copper bottles ) You are in danger of copper poisoning. Generally, by food processing laws, copper is not allowed to be in direct contact with food, as there is danger of copper contamination. Especially acidic liquids, like vinegar or citrus juices, directly slowly dissolve copper in presence of ...

20

This has to do with the chemical structure of the fatty acids. Single bonds create a straight molecule, which can be easily packed together to form a solid, while the double bond introduces a kink in the structure. Fats, which are mostly from animal sources, have all single bonds between the carbons in their fatty acid tails, thus all the carbons are also ...

20

This question raises more important issues than just the technical "why methyl ester," so I'll address those too. The easiest explanation for their focus on the methyl ester is that the ethyl ester just isn't nearly as sweet. This report says it is approximately $10\times$ less sweet (see Table VI on page 2689 and the entry '$\ce{Asp-Phe-OEt}$' with "$++$" ...

20

It doesn't make calcium carbonate rubbery, it removes the calcium carbonate. Egg shells are not purely calcium carbonate they are more like a composite with a continuous matrix of calcium carbonate and a smaller continuous matrix of protien. When you put the egg in vinegar, you etch away this calcium carbonate matrix leaving the formerly less noticeable ...

20

This is a nice well-defined question, and luckily there is excellent data for which we can provide a quantitative answer. Richard Wolfenden's research group has sought for many years to characterize the spontaneous (i.e. not enzyme catalyzed) rate of many enzymatic reactions. In general this is so that the spontaneous rate can be compared to the enzyme-...

18

The citric acid in lemon juice hydrolyzes the sucrose molecules into glucose and fructose as you heat the sugar. The water in the lemon juice is also part of this process. This mixture of monosaccharides is much less crystalline in the same way that most mixtures are less crystalline than pure substances. Wikipedia has a good article on this process under ...

18

An eggshell is a complex structure. From Wikipedia: Boiling the egg removes the waxy cuticle from the outside of the egg, dissolves a small but not insignificant amount of calcium carbonate from the shell, damages the protein matrix that holds calcium carbonate crystals in place in the shell, and can disrupt or destroy the two shell membranes. All of ...

18

It is the temperature of the pan that matters not the flame The flame temperature is irrelevant if you are cooking in a vessel. the only temperature you need to worry about is the temperature of the surface of the pan (or–even more importantly–the temperature of the meat). The surface of the pan will rarely get above around 220 °C if you are monitoring it. ...

17

It is essentially exactly what your teacher says: the term vitamin B complex is used because the structures assigned a name ‘vitamin Bx’ don’t really have anything in common although they are all somewhat important. As to why nobody ever uses vitamin K complex or vitamin D complex: well, at least in my country those vitamins are very under-represented when ...

16

Sodium bisulphate (NaHSO4): an acid Sodium bisulphiTe (NaHSO3): an antioxidant Sodium metabisulphiTe (Na2S2O5): another antioxidant In short, bisulphate and bisulphite are not interchangeable, but bisulphite and metabisulphite are. Sodium metabisulphite is prepared from sodium bisulphite via dehydration, as in this equation: \ce{2 NaHSO3 -> Na2S2O5 + ...

16

Why do juice taste awful? Awful taste is due to sodium laureth sulfate, also known as sodium lauryl ether sulfate (SLES), or sodium lauryl sulfate (SLS)- depending on which toothpaste you use. SLES and SLS are surfactants(wetting agent). Both chemicals are added in toothpaste to create foam and make the paste easier to spread around your mouth. Both ...

15

Greg hits most of the points, but there's one other angle I'd like to add: Practical Point of View: One of the well established Coca-Cola ingredients is decocainized coca leaf extract. The DEA is, to say the least, not exactly generous in allowing this import. This effectively prevents the manufacture of a Coca-Cola equivalent anywhere in the United States. ...

15

Based on appearance and extent of deformation, your bottle is likely made of PVC plastic which is not compatible with oils. Plastic bottles are made from blow molding. This process leaves residual stress in the polymer chains of the materials but creates a smooth and transparent surface. Lavender oil can diffuse into PVC and make it softer. Once it is ...

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