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ScienceNet is a World Wide Web resource database in Science. It is a community service project by Science Centre Singapore, supported by Nanyang Technological University and National University of Singapore.

We offer free electronic access to various topics in Science and Technology. Feel free to browse through our database and see if we have the answers to your questions.

Physical Sciences - Organic/ Phytochemistry
Q20246 :	What chemicals can be used to desolve solid compounds of carbon?
Q20142 :	Why silane are more reactive than their carbon analogus alkane?
Q20094 :	What are terpenoid, flavonoid, phenolic and alkaloid compounds? What are their usage in life especially in the field of medicine? What are the characteristics and classification of alkaloid, and what are the tests to indicate the present of alkaloid and its derivates?
Q20076 :	What are the compositions of Benedict solution and Fehling solution? How is the reaction between the Molisch reagent (alpha-naphtol) with sugar, Trommer reagent with sugar, and biuret with protein?
Q19897 :	I want to make homemade soap for personal use. I have found the supplier for food Lye in Singapore provision shop. They offer me a yellow and white lye. Kindly advise which should I chose to make soap? Thanks.
Q19752 :	When table sugar is heated to its melting point, it bubbles and turns black. When it cools, it remains a black soild. Describe the changes?
Q19667 :	Is periwinkle poisonous?
Q19314 :	I would like to know whether beta-carotene (dry-powdered form) is soluble in water. As there are always some that cannot be dissolved, will heating affect the functions of the beta-carotene?
Q19141 :	I am a chef, and I come in contact with onions and garlic on a daily basis. When my palms sweat the odour of them comes back. Is there remedy?
Q19065 :	I would like to conduct an experiment to measure the cholesterol contents in eggs. Please advise on the procedures and materials required to perform such an experiment.
Q18956 :	What is tartaric acid and where is it found?
Q18712 :	Are there any other indicators that one can make at home besides that from cabbage juice?
Q18620 :	I'm currently doing this science experiment about vitamin C and I need to know what the effects are on vitamin C in different conditions. I also want to know what the chemical composition and molecular structure of vitamin C. Furthermore, what is dehydroascorbic acid? Thanks for your time!
Q18317 :	If a sample of urea melted at 130 degrees C, what would you deduce?
Q18209 :	Why do potatoes change colour (from white to brown) etc.?
Q17963 :	Any idea why the carrot shreds in a carrot cake would turn (bright) green? I was trying 3 different recipes, and only one of them turned green. It had more baking soda and no baking powder, can orange carotenoids turn green when basic? I did cook it in an older metal pan, (the other two were in non-stick & glass pans). But the shreds were green all the way through the cake, not only at the outside. Also, that cake was made with oil, not butter as the other two were, and was much darker in colour (brown). Finally, I didn't actually notice the green colour until the second day, but I don't know if that was because I was distracted at first, or if the colour didn't develop until later.
Q17780 :	Is luminol naturally occurring or synthetic or both? What is luminol's toxicity?
Q14928 :	How can we create chemiluminescence reaction? What is luminol? How/where can we obtain/buy luminol and other chemicals required?
Q14828 :	Carboxylic acid + alcohol --> ester + water The question: why should the reaction be kept free of water during heating?
Q14442 :	What is the IUPAC name and structural formula of isooctane?
Q12246 :	When some sugar is poured on a metal spoon and is heated over a candle flame, the sugar caught fire after some time. What does the result show?
Q12229 :	What is the equation for the hydrolysis of sucrose using hydrochloric acid?
Q12201 :	May I know what is cellulase? What is its function?
Q11955 :	What are the names of the acids in juices such as grape and peach?
Q11907 :	Can you please give me information on cooking oil?
Q11906 :	What is rubbing alcohol?
Q11808 :	Is mannitol a reducing sugar? What is the difference between amino acids, polypeptides and proteins?
Q10827 :	What are some chemical properties of cellulose?
Q10187 :	What is the chemical formula of flour?
Q9225 :	What are starch and cellulose? What are their differences and similarities (if any)?
Q8590 :	Is starch polymer?
Q7599 :	What is the chemical formula for polyisoprene?
Q6752 :	What does the molecule of glucose C₆H₁₂O₆ look like?
Q6425 :	What is the shape of sugar crystal?
Q6087 :	What are reducing sugars?
Q5751 :	How is formic acid manufactured? How does it occur in ants and such?
Q5550 :	What is the formal name for the acid in lemon and lime juice?
Q4936 :	What are the active ingredient or chemical components in pandan leaves?
Q4878 :	Is aspirin an acid or base?
Q4151 :	When preparing esters why do you have to add sulphuric acid?
Q3609 :	What reaction makes the newspapers turn yellow after a long time?
Q3564 :	Most literatures record the C=C can be cleaved by the action of (ozonolysis) or acidified permanganate. However, there is one book that records that C=C can also be cleaved by refluxing alkene with acidified dichromate. Is it true that C=C can be cleaved by hot acidified dichromate under certain conditions? Please enlighten me further.
Q3470 :	When ethane undergoes chlorination reaction in the presence of ultra-violet light, hydrogen is substituted by chlorine and chloroethane is formed. If fluorine is added to chloroethane, will fluorine be able to displace chlorine to form fluoroethane?
Q3260 :	How does acid denature the protein in egg white? How does beating of egg white denature proteins?
Q3112 :	What is meant by denaturation?
Q2694 :	What is the production process of DDT? And what is its chemical formula?
Q2693 :	How do you make rock sugar? Which materials can be used? What temperature should it be heated to? How do you get the sugar to crystallise nice?
Q2605 :	I have learnt from chemistry that phenol is an acidic compound that consists of a hydroxyl group bonded to a benzene ring. Then may I know what a phenyl group is? Does the word 'phenyl' specifically refers to aromatic compounds with an ?OH group? Why is it that I have come across some aromatic compounds that are named phenyl XXX when it does not contain an ?OH group?
Q2403 :	What are the chemical properties of polyisoprene?
Q2367 :	What are the techniques that can be used to study protein-nucleic acid interactions?
Q2353 :	How do we make sugar crystals?
Q2236 :	Why do taxi drivers in Singapore put pandan leaves in their cars?
Q2141 :	How does vitamin C works as an antioxidant? In addition, when vitamin C is dissolved in potassium permanganate solution, can vitamin C prevent potassium permanganate from reacting with the air? Thank you.
Q2002 :	I am doing a project on bananas on why they turn black brown after a while. I want to know the biology and chemistry of it. I have not been able to find any information online and I am wondering if you can provide some help. I am also curious why dehydrated (dried) bananas do not turn brown. Thanks.
Q1992 :	What is the chemical formula of bromothymol blue?
Q1816 :	What are anthocyanins?
Q1639 :	What is Ethyl Methyl Phenyl Glycidate, and what is it used for? What is Gamma nonalactone and what is it used for? What is Gamma undecalactone and what is it used for? And, what is Laevo Linalol and what is it used for? I understand all of these have something to do with perfume production and or development, but I would like to understand these elements more fully.
Q961 :	What is the chemical name for the brown liquid you obtained from burning sugar?
Q875 :	What is the pH value of apple, orange, potato and carrots?
Q456 :	Why are amino acids called acids when they have some members having acidic properties while others having basic properties. I read that amino acids form zwitterions in water. What exactly are zwitterions and do they act as electrolytes as other ions do?
Q163 :	How is vinegar made?

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