Preliminary Test and Solubility Classification of Organic Compounds

shiter Test and solubility Classification of native Compound Keene Louise Topacio, Christopher Jay Robidillo Abstract The experiment focuses on how to contraryiate thoroughgoing complicateds by its operable throngs. It is d unrivaled by forward taste and with the solubility analyse. feeler shield apply 2 cognise conglomerates alike the unappreciateds. Physical state, pretext, odour, and fire examination were noted. The known compounds be in original and perfect compounds. A coincidence is make from the bill in the unknown warning, by which we had reason t wear on that point were two positive compounds and one in ingrained among the unknowns.In sight to entertain a smashed background ab let out the solubility campaign, we first categoriseify organic compounds of known running(a) separate using the said test. Butyl platitude, grain alcohol sucrose, butyraldehyde, ethanoic loony toons, methyl aminoalkane, nitrophenol, diethyl ethoxyethane, ben zoic paneling and propanone were used. It is establish out that they atomic number 18 class X, Sn, S, N, Sa, Sb, S, N, A1 and Sn, respectively. We use pissing, ether, HCl, NaOH, NaHCO3, H2SO4, litmus root word, and phenolphthalein in baring each compound base on their solubility and color change. It follows a current scheme on testing the compound.Each test leave alone link to an separate test until we ended up with the class of that compound. We finally determine the class of the collar unknowns. It is open up out to be an Sb amine -, S -salt -, and an N - remindful compound-. Keywords solubility, classification, organic compounds, solubility test, preliminary test Introduction One primary(prenominal) deduct of experimental organic chemistry is to be able to disassemble and expose an unknown organic compound from its useful crowds. There argon several steps in order to acquire this and there is no definite process. But there be doctrinal ways in unlike experime ntal organic chemistry books.For this experiment it go away evince the preliminary examination and solubility characteristics of around known organic compounds and unknown smacks. Preliminary test is fundamentalally noting studys with lesser effort comp atomic number 18d to the different tests the physiologic state, color, odor, and its ignition properties. Physical state of a substance earth-closet experience a distinction among organic compounds for the reason that at room temperature close to of organic compounds ar in its tranquil state. This is cod to the intermolecular forces of tenderness in the compound. The color is also informative because most pure organic compounds ar white or colorless.Some discolorations of brown color be effect of oxidation defendion. The odor of many organic compounds, especially the ones that learn lower molar mass argon steeply distinctive. Also, useable separateings conduct its own different touch concomitantly alcohols, ketones, esters, aliphatic and aromatic hydro carbon physical compositions. perplexity must be detect while stinking the unknown try on because large amounts of organic vapors should never be inhaled because of toxicity. The ignition test involves a procedure in which a drop or two of a liquid or about 50-100 mg of a fast is heated gently on a crucible with a bunsen burner burner flame.Whether a material melts at low temperature or besides upon thaw much strongly is and so(prenominal) noted. The flammability and the nature of any flame from the sample atomic number 18 also put down. A yellow, sooty flame is indicative of an aromatic or a highly unsaturated aliphatic compound a yellow but non-sooty flame is characteristic of aliphatic hydrocarbons. The atomic number 8 study of a substance makes its flame more colorless or downhearted high oxygen content lowers or prevents flammability, as does halogen content. The unmistakable and unhappy odor of sulfur dioxide indi cates the presence of sulfur in the compound.If a white, nonvolatile balance wheel is left after ignition, a drop of piddle is added and the resulting sedimentary solution is tested with litmus or pHydrion wallpaper a metal(prenominal) salt is indicated if the solution is alkaline. Solubility of an organic compound in different firmness of purposes put forward present useful but not efficient information about the presence or absence of certain functional groups. It is because the can buoyonic principle in solubility is a interchangeable(p) dissolves like. In order to have a more distinct result a systematic approach arse be considered and it is by solubility classification. First is to test the solubility of the unknown in water.Several structural features of the unknown fuel be deduced if it is water- meltable. It must be of low molar mass and will usually contain no more than four to five carbon atoms, unless it is polyfunctional. Also, it must contain a glacial gro up that will form a hydrogen bond with water, such as the hydroxy group of an alcohol or a carboxyl sultry, the amino functionality of an amine, or the carbonylic group of aldehydes or ketones. Esters, amides, and nitriles dissolve to a lesser extent, and acid. chlorides or anhydrides react with water rather than simply breakup in it.Test in ether for water disintegrable compounds are also observed this is to identify nevertheless the functional groups in ther unknown. On the some other hand, alkanes, alkenes, alkynes, and alkyl halides are water-in fat-soluble. Supplementary test such as solubility in hydrochloric acid, then sodium hydroxide, sodium bicarbonate, and finally tested in sulphuric acid must be done accordingly. Solubility in one or more of these acids and bases is defined in terms of the compound being more soluble in base or acid than in water and reflects the presence of an acid-forming or basic functional group in the water-insoluble unknown compound.Methodo logy The experiment was divided into two parts and the group was given three unknowns. The first part was for the preliminary test. Data were recorded according to the somatic state, color, and odor of the compound. Small amount of the test compounds, slovenly person nitrate, acetic acid also the unknowns were placed in separate porcelain crucible. It was then heated and covered. Observations were noted. If balances were sighted it was tested for acidity or basicity using a drop of distilled water and a litmus paper. Also, a drop of 15% HCl was added to determine if there was formation of hit man.Lastly, flame test using a nichrome wire was also observed in order to determine if metals were present. For the fleck part of the experiment, solubility class test. 1mL of the solvents water, ether, HCl, NaOH, NaHCO3, and H2SO4, were placed on separate micro test tubes. A drop or pinch of the test compounds butyl bromide, ethanol, sucrose, butyraldeyde, ethanoic acid, methylamine, ni trophenol, diethyl ether, benzoic acid, propanone, and the unknowns, were added to the solvent. It was then conflate and observed if it dissolved or not, miscible or not, or if there are discoloration present.The solubility flow graph was used in order to classify the compounds. Results and Discussion Preliminary test determines the physical state, color, odor, and the combustion reaction of the compound during ignition. It is shown in delay 1. That squealer nitrate which is blue liquid has an odorless smell while it produces a green flame when it is ignited. On the other hand, an organic compound, acetic acid, is liquid and is colorless. It has a sour smell and it produces no residue when it is ignited. With respect with our group samples, all are in liquid state while differs in odor.A1 has a very foul odor, while A2 possess an alcohol like then A3 have a strong odor. A1 and A3 does not have a residue after it was heated it yet evaporated and evolution of smelly (unpleasant) g as was also observed. In the case of A2 there were close to black residue and after ignition, a red flame was observed. Table 1 Preliminary Examination Data X Cu(NO3)2 C2H4O2 A1 A2 A3 A unstable Liquid Liquid Liquid Liquid B Blue dull Colorless Colorless Colorless C odorless sour foul Alcohol like Strong D Green flame orange No residue red orange X compounds, A physical state, B color, C odor, D ignition test Copper nitrate and acetic acid are both in liquid phase. Normally, an organic compound such as acetic acid is a colorless liquid. Copper nitrate, on the other hand, is in aqueous form. Although they are in the said(prenominal) phase, it doesnt mean that they have the same volatility and solubility. Upon ignition, their volatility differences are noticed. The presence of ash is observed in copper nitrate while on acetic acid there is no present. It is an sign that there was solid present in copper nitrate solution.Since a solid is not volatile, we can easily identify t he presence of solid upon ignition. Thus, it is an indication that the physical state of copper nitrate is actually solid. Finally, copper nitrate has color while acetic acid has none. It is because of the presence of metal in the aqueous copper nitrate. While for our unknowns, it was all in liquid form which has an ammonia-like smell A1, alcohol like smell A2 and strong smell A3. By that, the one will know that A1 is already an amine. When it is ignited, it produces no ash and no soot. It is an indication that there is no metal present.Also, we found out that it was an organic compound because the observation was interchangeable with acetic acid. By all obtained observation, it is possible that A1 is an amine. For A2, it was observed that it contains metal, for the reason that when it ignited the flame was red with that we could say that it is a salt. vague A3, was found out to be an organic compound because the observation was similar with acetic acid. We cant determine the comp ound with just preliminary test due to the insufficient entropy. Table 2. 1 Solubility Test Data Y C4H9Br C2H5OH C12H22O11 C4H8O C2H4O2A B C D E F G - - - H - colorless - - colorless I X Sn S N Sa Y Compounds, A Water, B Ether, C HCl, D NaOH, E- NaHCO3, F- H2SO4, G Litmus Paper, H Phenolphthalein, I Solubility Class Table 2. 2 Solubility Test Data (Known) It is found out in Table 2. 1 and 2. 2 that ethanol, sucrose, nitrophenol, ethanoic acid, methyl amine, diethyl ether and propanone are soluble in water while butyl bromide, butyraldehyde, and benzoic acid are not. (Table 2. can identify the intermolecular forces of attraction and polarity from the structure and the functional group) Since water is a polar compound (possesses hydrogen bond) it is a poor solvent for saturated hydrocarbons. As we all know, saturated hydrocarbons are not polar because they only posses Van der Waals intermolecular force. referable to long chains (or high mol ecular weights) do not affect by polarity peachyly unsaturated hydrocarbons such as aromatic hydrocarbons have similar solubility with saturated hydrocarbons. The introduction of halogen atoms does not alter the polarity appreciably.It does no attach the molecular weight, and for this reason, the water solubility falls off. On the other hand, salts are extremely polar, the ones encountered in this work generally being water soluble. Y CH5N C6H5NO3 C4H10O C6H5COOH C3H6O A B C D E F G - - - H pink colorless - - colorless I Sb S N A1 Sn Y Compounds, A Water, B Ether, C HCl, D NaOH, E- NaHCO3, F- H2SO4, G Litmus Paper, H Phenolphthalein, I Solubility ClassAs might expected, acids and amines generally are more soluble than neutral compounds. The amines believably owe their abnormally high solubility to their dip to form hydrogen-bonded complexes with water molecules. This theory is also linked with the fact that the solubility of amines dimi nishes as the basicity decreases. It also explains the observation that many tertiary amines are more soluble in cold than hot water. Apparently at lower temperatures, the solubility of the provide is involved whereas at higher temperatures the hydrate is unstable and the solubility measures are that of the free amine.Ethers, esters, ketones, aldehydes, alcohols, nitriles, amines, acids and amines may be considered together with respect to water solubility. Due to their similarity in structure with water, their solubility is high. For that, the solute-solvent interaction is strong because of their compatibility made possible by their honey oil polarity. Because of the polar nature of water compounds owe their solubility in it almost entirely to the polar groups which they may contain. The functional groups stated above are hydrophilic. As the hydrocarbon percentage increases, the hydrophobic part also increases.As a result, the solubility in water of these compounds containing fu nctional groups, decreases as the hydrocarbon chain is getting longer or the ring is present. The tendency of certain oxygen-containing compounds to form hydrates also contributes to water solubility. The stability of this hydrate is therefore, a factor in determining water and ether solubility. These compounds have great solubility in water because of their capability to form hydrates. It is the reason wherefore diethyl ether and propanone are soluble in water.On the other hand, although generally, aldehydes are soluble in water, butyraldehyde is not. It is due to long chain of the butyl hydrocarbon. For the same reason as for long chains of amines, aromatic alcohols and aromatic carboxylic acid do not exhibit solubility in water. greater number carbon chains due to ring decreases the effect of polarity. For propanone, it doesnt just dissolve in water. It undergo reaction which is a nucleophilic assenting reaction. As a consequence, it yields a diol. As for the compounds that are water soluble, we can still further classify them through their solubility in ether.It is obtained that ethanol, ethanoic acid, methyl amine, propanone are soluble while insoluble compound are sucrose and nitrophenol. Since dipole bond is present on ether groups, it can differentiate short chain ethers, alcohols, carboxylic acid, ketone and amines from doughs. Ethers cannot dissolve carbohydrates, such as sucrose. Thus, it can be classified as class S. Table 2. 3 Structure and Functional Groups of Known Compounds Compound Structure Functional group Butyl bromide, C4H9Br Alkyl halides Ethanol, C2H5OH alcohols Sucrose, C12H22O11 Carbohyd-ratesButyraldehyde Aldehydes Ethanoic acid Carboxylic acid Methyl amine Amines Nitrophenol Alcohols Diethyl ether Ethers Benzoic acid Carboxylic acid Propanone Ketone The water soluble organic compounds that are also soluble in ether are monofunctional group compounds. We can classify their functional group base on their acidity and basici ty and it is done with the use of litmus paper. When the blue litmus paper is dropped in the test compounds, only at ethanoic acid the litmus paper changes its color to red while at ethanol, methyl amine, diethyl ether and propanone.On the other hand, when red litmus paper is dropped on the test compounds, only methyl amine dour the R. L. P to blue while it remained at red for ethanol, diethyl ether and propanone. By that, we concluded that, ethanoic acid is an acid, methyl amine is a base while ethanol, diethyl ether and propanone are neutral. In the other realm, water-insoluble compounds such as butyl bromide, butyraldehyde, nitrophenol and benzoic acid are further tested with 5% HCl. It is obtained that none of these compounds are soluble in the disregard HCl.The explanation for this is that the acid can only dissolve are basic amines. Aliphatic amines (of any class) forms salts (a polar compound) when it is mixed with the dilute acid because of its basicity. 5% hydrochloric ac id is also polar so they are soluble. Those compounds that dissolve in 5% HCl will probably fall under class B, which are amines. Compounds that are insoluble in 5% HCl (all compounds) are then tested with 5% NaOH. It is observed that only benzoic acid is the only soluble compound. Compounds dissolve in aqueous base solutions because they form sodium salts hat are soluble in aqueous medium. Probably, it is the only compound which is sufficiently acidic to form salt with the dilute base. Upon comparison, carboxylic acid is the functional group which is the most acidic among all organic functional group aside from sulfonic and sulfinic acids. To prove it, we can compare the acid constant of the functional group of each compound tested. The soluble benzoic acid can still be classified as either a strong organic acid and as a weak organic acid. Upon mixing, it is found that it is a strong organic acid because it dissolves with the reagent.Thus, benzoic acid will fall under class A1 The compounds insoluble with 5% NaOH which are the butyraldehyde and butyl bromide and diethyl ether are further categorized. Upon mixing those compounds with the concentrated sulfuric acid, only butyraldehyde dissolves. So, butyraldehyde is on class X, while butyl bromide and diethyl ether are on class N. As we all know, butyraldehyde contains a functional group with oxygen (aldehyde), so it can undergo sulfonation with the concentrated acid. On the other hand, butyl bromide is saturated and has no functional group with O atom so it cant undergo sulfonation.Thus it is not soluble. Table 3. 1 Solubility Test Data (Unknown) unknown A B C D E F 1 2 3 A Water, B Ether, C HCl, D NaOH, E- NaHCO3, F- H2SO4 For solubility test of the 3 unknowns of the group, it is on Table 3. 1 and 3. 2, we initially confirm its solubility in water. It is found that A1 and A2 are soluble. From that, we can anticipate that our sample can be a monofunctional group compound with short chain or a carbohydrate or salts. So, the next steps for the water-soluble compounds were to check its solubility with ether.When we mixed ether and our samples were immiscible dissolves. From that, we may say that one is a salt. From the smell of the unknown A1 we already know that it will fall under amine that has a short chain so we stll tested it with litmus paper because amine are basic. It is observed that when red L. P. is exposed in the sample, it turned to blue, whereas the blue L. P. have no color change when it is exposed. It is an indication that our sample is basic. Thus, our assumptions are correct that it is a short-carbon chain, monofunctional amine and it falls under class SB. Table 3. Solubility Test Data (Unknown) unknown 1 2 3 a - b Pink - colorless c Sb S X Possible compounds Monofunctional alcohols, aldehydes, ketones, amides, esters, aromatic amines, nitriles, and amides with five or fewer carbons. Salts of organic acids amine hydrochlorides, amino acids, polyfunctional compounds with hydrophilic functional groups, carbohydrates, polyhydroxy compounds, polybasic acids, etc. pure hydrocarbons, haloalkanes, arylhalides, other deactivated aromatic compounds, diaryl ethers a Litmus Paper, b Phenolphthalein, c Solubility ClassFor A3, being immiscible to water it was tested with HCl, NaOH, NaHCO3, and H2SO4 for its acidity or basicity. Unfortunately, it failed the entire tests so sum it up to a class X compound. Conclusion The objectives of the experiment were obtained. We were able to examine compounds by using the preliminary test. We were able to recognize the solubility class of each known compound given to us with the aid of solubility test. Finally, we were also able to classify organic compounds based on their solubility in some other compounds and on their acidity and basicity.The synopsis and identification of organic compound for this particular experiment consists of two parts which are probably adopted from common scheme s. This systematic approach enables us to have a precise analysis without spending much reagents, thus it is useful and efficient tool of identifying organic compounds. Both preliminary test and solubility test are considered. We concluded that preliminary test and solubility test are effective ways of classifying organic compounds. In preliminary test, we had seen the different properties of different compound by its physical state, color, odor and ignition test.We had compared the result of our unknown sample with the known ones, and upon comparison, we concluded that our sample is an organic compound which contains no metal. We had differentiated an organic compound from a non organic compound. An organic compound may be in a form of a solid or liquid, may be colored or not depending on the degree of conjugation, produces odor and has no ash during ignition because of the absence of metal. For our unknown sample, the significant observation is that its fishy, ammonia-like smell. Since it is an organic compound, we can say that it is an amine.By the study of solubility data it has been found possible to lay down certain generalizations which often enable one to predict the solubility behavior of a compound barely by inspection of its structural formula. In the solubility test, we found out the different class of the different organic compound. It is obtained that water soluble compounds are compounds which have a short-carbon chain compounds with monofunctional group and are carbohydrates. For ether, it is capable dissolving short-carbon chain compounds due to their common polarity.It is a way of differentiating carbohydrates from that. For those ether-soluble, their classifications are place based on their acidity or basicity since they are monofunctional. Acidic groups are carboxylic acids, basic groups are amines while neutral groups are alcohols, aldehydes, ketones, and some carboxylic acid derivatives except the acid halides and anhydrides. For those insoluble compounds, a test for solubility with 5% HCl is made to identify strong bases such as amines that have longer chains or aromatic ring. The dilute acid can only form salt with strong bases, to dissolve.On the other hand, 5% NaOH is then used to check for the presence of acidic organic compounds. For acids, they can form salt with strong base such as NaOH, thus making it soluble. The 5% NaHCO3, which is a weak base is used to identify the degree of acidity of those obtained acidic organic compounds. Strong acidic acids are soluble with 5% NaHCO3 while weak organic acids are not. Lastly, neutral compounds with long chains or ring remained. The concentrated sulfuric acid is used in identifying functional group that has O and organic compounds that are unsaturated.Those compounds undergo sulfonation, making it soluble with the reagent. Solubility plays a major(ip) role in the identification and characterization of an organic compound. Through certain chemical tests, one can ide ntify an organic compound. These concepts regarding the solubility of organic compounds are primarily applied in identifying the nature and properties of carbon-containing compounds as rise up as predicting their behavior and reaction mechanism when allowed to be reacted with specific solvents during different chemical processes. References Baluyut John Y. G. , De Castro Kathlia A. Organic chemical science Laboratory for Chemical engineering science Students Part 2, 2004 Klein, David (2012). Organic Chemistry. Danvers. John Wiley & Sons, Inc. , Gilbert, John. Experimental Organic Chemistry A miniscale and Microscale Approach 5th Ed. Australia, Brooks/Cole Cengage Learning. http//www2. volstate. edu/chem/2020/Labs/classification. pdf http//www. sharjah. ac. ae/English/Academics/CentralLabs/asl/cl/Pages/IdentificationofOrganicCompounds. aspx http//www. wellesley. edu/Chemistry/chem211lab/Orgo_Lab_Manual/Appendix/ClassificationTests/index. html http//wwwchem. uwimona. edu. jm/lab_ma nuals/c10expt25. html