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What else can I help you with?
Given a pure sample that is either pure benzoic acid or 2-naphthol give a procedure that can be used to determine the identity of the sample?
Lets see. Add neutral ferric chloride to the sample solution. A coloured solution is obtained if it is 2-naphthol (most phenols give colour with neutral ferric chloride solution). Add sodium bicarbonate to the sample solution. Carboxylic acids evolve carbon dioxide gas. Phenols (except strong ones like picric acid) does not. Both 2-naphthol and benzoic acid will evolve hydrogen when treated with metallic sodium (test not advisable to do) and NaOH. Phenols form pleasent smelling esters when treated with carboxylic acids where as benzoic acid will be fruity odour with alcohols or phenols. Both benzoic acid and 2-naphthol melts about 1220C whereas the boiling point of benzoic acid is 2490C and that of 2-naphthol is 2850C.
Why you dissolve absolute ethanol in 5 percent alpha naphthol for the Molisch test?
There is an answer in 'Related links', clickable just below this answer page [cf. Molisch's test for carbohydrates).But there is no conformation to use absolute alcohol (100%), neither of 5% a-naphtol.They use normal 96% alcohol and a-naphtol 2 g per 20 mL (=10%).The site is in German language, but you'll find an 'English language' link below the 'disclaimer'.
What are the reagents used in voges-proskauer tests?
The reagents commonly used in the Voges-Proskauer test are alpha-naphthol and 40% potassium hydroxide (KOH). These reagents are added to the bacterial culture after the addition of the Barritt's reagent (a mixture of 5% alpha-naphthol and 40% KOH) to detect the production of acetoin, which is indicative of certain bacterial species such as Enterobacter and Klebsiella.
What is difference between melting point and drop melting point?
The melting point is the temperature at which a solid substance transitions to a liquid state. The drop melting point is a method of determining the melting point where a small amount of the substance is heated until it melts and then allowed to drop onto a solid surface to observe the melting point. Drop melting point is often used when the substance being tested has a high melting point or when observing the melting process is critical.
The temperature at which a solid melts is called?
The temperature at which a solid melts is called the melting point. At this temperature, the solid transitions into a liquid state.
What is the melting point of phenyl-azo beta-naphthol?
The melting point of phenylazo- beta-naphthol is somewhere from 131 to 133 degrees Celsius. Phenylazo- beta-naphthol is also called as Sudan I.
What is the difference between alpha and beta naphthol?
alpha naphthol with CCl4(carbon tetrachloride) gives blue colour whereas beta naphthol with CCl4 gives no colour. that is the distinction test between alpha and beta naphthol.
What is the melting point of fifty percent 2-naphthol and fifty percent benzoic acid?
The melting point of a mixture of 50% 2-naphthol and 50% benzoic acid will depend on the exact proportion of each compound present and any potential interactions between them. However, the melting points of the individual compounds are approximately 122°C for 2-naphthol and 122-123°C for benzoic acid.
What would happen to the melting point of pure benzoic acid if 2-naphthol was mixed in?
The literature value of the melting point of pure benzoic acid is about 122.4 degrees Celsius, while the literature value of the melting point of pure 2-naphthol is close at 122 degrees Celsius. Nevertheless, the melting point of the benzoic acid should be depressed (go down) compared to the literature value if you were to add 2-naphthol because the sample you were testing would then be impure, even if that impurity does have a similar melting point. Also, the range over which the sample melts should get larger as well. Instead of melting within a degree or less, it may melt over the course of several degrees. So I just tested this in lab, and I can't promise that this is 50/50, but my melting point for 2-naphthol with Benzoic acid is 104.1-106.0 degrees Celsius This is a very basic answer, and the trend is true. However, with my organic chemistry professor, this answer would be followed by a blank look and "Why?" The best way to think of this is to look at the chemical structure of Benzoic Acid and 2-naphthol separate. Go ahead and Google it on a new tab. Now look at the molecule of the two together. And think: "What does the composite molecule have that the two alone don't?" Give up? Electronegativity. The more electronegative a molecule is the greater its reactivity. As in the compound molecule will melt easier than the two 'pure' substances.
How could you seperate benzophenone from a-naphthol?
The melting point for lauric acid is about 45 degrees while it is 121 degrees for naphthol. So, in a mixture repeated cycles of slow warming and cooling should separate out lauric acid from naphthol. You can improve the efficiency by adding a dash of slightly acidic 70% isopropyl alcohol. This will deprotonate the lauric acid while maintaining the proton on naphthol during this process to enhance separation and purification of the two compounds. You could also flat-out distill the two products by maintaining the temperature of the solution at the boiling point of lauric acid to separate it from naphthol.
What kind of compound is a-naphthol?
A-naphthol is a type of organic compound known as a naphthol, which is a phenol derivative. It consists of a naphthalene ring structure with a hydroxyl group attached at the alpha position. A-naphthol is commonly used in the production of dyes and pigments.
Why fructose give intense violet coloration with alpha naphthol in acidic media?
when it is kept in acid media,the acid hydrolyses the glycosidic bond and yields monosaccharide to give furfural and its derivatives ,these products when react with alpha naphthol (sulphonated) they give a purple complex
Given a pure sample that is either pure benzoic acid or 2-naphthol give a procedure that can be used to determine the identity of the sample?
Lets see. Add neutral ferric chloride to the sample solution. A coloured solution is obtained if it is 2-naphthol (most phenols give colour with neutral ferric chloride solution). Add sodium bicarbonate to the sample solution. Carboxylic acids evolve carbon dioxide gas. Phenols (except strong ones like picric acid) does not. Both 2-naphthol and benzoic acid will evolve hydrogen when treated with metallic sodium (test not advisable to do) and NaOH. Phenols form pleasent smelling esters when treated with carboxylic acids where as benzoic acid will be fruity odour with alcohols or phenols. Both benzoic acid and 2-naphthol melts about 1220C whereas the boiling point of benzoic acid is 2490C and that of 2-naphthol is 2850C.
What is the resonance of alpha naphthol?
The resonance structure of α-naphthol involves delocalization of electrons within the aromatic ring through the oxygen atom. This results in stabilization of the molecule due to electron delocalization, making the compound more stable.
Why you dissolve absolute ethanol in 5 percent alpha naphthol for the Molisch test?
There is an answer in 'Related links', clickable just below this answer page [cf. Molisch's test for carbohydrates).But there is no conformation to use absolute alcohol (100%), neither of 5% a-naphtol.They use normal 96% alcohol and a-naphtol 2 g per 20 mL (=10%).The site is in German language, but you'll find an 'English language' link below the 'disclaimer'.
What are the reagents used in voges-proskauer tests?
The reagents commonly used in the Voges-Proskauer test are alpha-naphthol and 40% potassium hydroxide (KOH). These reagents are added to the bacterial culture after the addition of the Barritt's reagent (a mixture of 5% alpha-naphthol and 40% KOH) to detect the production of acetoin, which is indicative of certain bacterial species such as Enterobacter and Klebsiella.
What do you call the temperature at which a solid changes to a liquid?
This is the melting point.
