One equipment melts a chemical at 121–122°C whereas another melts it at 129–130°C. Sadly, neither device is calibrated. How can you identify your sample without calibrating either instrument?
Q: What will be the composition of the vapor when a mixture containing 0.30 of A was subjected to…
A:
Q: A student obtained a solid product in a laboratory synthesis. To verify the identity of the solid,…
A: To give the reason: the difference in melting points? reason for the change in the melting point?
Q: Using the given TLC plate can you describe the results and what does the TCL plate tell about the…
A: To describe the results on TLC plate for purity.
Q: What is each cycle of a simple distillation called? Theoretical plate Distillate…
A: Simple distillation is process of separation.
Q: Calculate the heat loss or heat gain of the 3 solution mixtures (qrxn). Then calculate the ΔH for…
A: Mass = Volume × Density qreaction = Mass × Specific heat capacity ×temperature change
Q: What are the principles behind caffeine being extracted from coffee using the above items?
A: Caffeine extraction from coffee
Q: Q2. Find the following quantitative analysis which has been done by the DSC ( 2- Bromopropane) for…
A: The negative enthalpy represents that the process is exothermic i.e. the heat is liberated during…
Q: True/False: While emulsions and microemulsions consist of the same 3 ingredients; aqueous phase, oil…
A: True.
Q: Consider the following statements as they apply to gas chromatography. Decide if each is true or…
A: 1. Temperature programming is often employed for samples with a wide range of boiling points.…
Q: How could we verify that two different samples, with the same melting points, are the same compound?…
A: Melting point of pure compound is always sharp or have very narrow range Melting point of mixture…
Q: In which of the following cases would recrystallization be favored over extraction when purifying a…
A: Recrystallisation is a technique that is used for purifying the non-volatile organic compounds.…
Q: What volume (in mL) of the prepared high alcoholic elixir is needed if Rx requires 120 mL of an…
A: A multiple choice question based on measurement that is to be accomplished.
Q: Remember how you learned that a pure liquid distills within a narrow boiling point range, but that a…
A:
Q: omega-3/g oil, respectively. Calculate the omega 3 extraction efficiency for each temperature based…
A: Weight of kernels crushed for extraction of omega-3 = 5 g (i) From the % yield, calculate the amount…
Q: Sketch a flow chart of the entire caffeine extraction and purification used in the laboratory…
A: To prepare a flow chart for the extraction of caffeine and purification used in the laboratory. The…
Q: You measured the melting point of the recrystallized product Ttal=142,2-145,5°C. Based on this…
A: Given that, Melting point of recrystallized product = 142.2℃ to 145.5℃ .
Q: Nacl: NaCl dissolution: (aq) predicted AS value for NaCl dissolution: NaNO3: NANO3 dissolution:…
A: In the given question solid, liquid and gasesuos state find
Q: is 77.18%. The melting point range of crude benzoic acid = 112-119°C and the melting point range of…
A: The question is based on the results obtained after recrystallizing benzoic acid. the yields and…
Q: Of Aspirin, ethanol, acetaminophen, ethyl acetate, hexane, and water which could go undetected…
A: HPLC or high perfomance liquid chromatography is a usefull technique to separate and analyse…
Q: The mobile phase taken in the TLC jar can be one of the following a mixture of two inert gases a…
A: Pic 1: a solvent or mixture of solvents ( We use solvent like EtOAc or EtOAc and hexane mixture in…
Q: The entire mercury bulb of the thermometer must be below the level of the side arm in order to…
A: “Since you have asked multiple questions, we will solve the first question for you. If you want any…
Q: 1. Shown below, a student spotted the three-component mixture onto a TLC plate and developed it…
A: To determine the order in which the given molecules present in the analytical mixture will appear on…
Q: Draw and label a moisture sorption isotherm for any product of your choice at different temperature…
A:
Q: Shown below, Baker spotted the three-component mixture onto a TLC plate and developed it using the…
A: A question based on analytical separations that is to be accomplished.
Q: 1. Before manufacturing process begins the sources of suitable fragrances are ______ in the…
A: 1. This sentence is about the manufacturing of a perfume in the manufacturing center. Collection is…
Q: Imagine you are an organic chemistry student who isolates a crude sample of salicylic acid following…
A: The melting point is largely dependent on the impurities present in the substance. If there are…
Q: During the microscale boiling-point determination of an unknown liquid, heating was discontinued at…
A: After sealing the bell it is turned upside down and placed in a capillary tube having the liquid…
Q: Upon running a standard recrystallization in 90:10 EtOH:water you reach a point where crystals are…
A: In recrystallization process , we have a certain method to induce crystallization if crystal don't…
Q: Jamar spotted the three (3) component mixture shown below to a TLC plate and developed it using the…
A:
Q: Use a chemical dictionary, chemical text or encyclopedia to find a specific definition of…
A:
Q: Contrast the physical appearance of the crude material before the recrystallization and that of the…
A: A question based on re-crystallization, which is to be accomplished.
Q: The melting point (mp) range of reference compound A is 320-340°C. The mp range of a 1:1 mixture of…
A: Given, Melting point range of compound A is ---- 320-340oC. Mixture of compound A and unknown…
Q: A chemist is asked to separate the components of a mixture composed of 1.00 g each of the two…
A: The given chemicals to be separated are 2-naphthol (pKa = 9.5) and 2-naphthylmethanol(pKa = 16).
Q: Which of the following consideration are applied when choosing a suitable recrystallization solvent?…
A: Recrystallization is the technique use to purify solids using specific solvent. Characteristics of a…
Q: A student recrystallized some impure benzoic acid and isolated it by filtration. He scraped the…
A: Recrystallization can be defined as the process in which old arrangement of particles in the crystal…
Q: The best liquid mixtures for separation by simple distillation need to have boiling points that…
A:
Q: 1a. Use the given table to construct a temperature-composition diagram for cyclohexane Toluene…
A: The temperature composition phase diagram represents the information about a binary mixture in…
Q: (1) Fill in the table with the missing properties for H20 T (°C) P (kPa) v (m³/kg) 0.001080 State…
A: Solution -
Q: What is the main drawback of using steam distillation in the isolation of volatile oils from its…
A: The process of separation or purification in which the components of a mixture are separated which…
Q: In recrystallization, crystals gathered are washed with cold solvent. What would its effect on…
A: When a reaction is carried out, the product obtained is mostly accompanied by some other substance…
Q: In normal phase TLC, the mobile phase is polar than the stationary phase. Consider the TLC plate…
A: "Since there are multiple sub-parts in this question and it is not mentioned that which one has to…
Q: Extraction of the aqueous salicylic acid solutions with 10% ethyl acetate/hexane (density ~ 0.7…
A: As you have posted two independent questions in a single request, we will solve the first question…
Q: In order to carry out a highly accurate determination, usually of a valuable constituent in a…
A: The researchers or chemist always doing research on the basis of qualitative or quantitative…
Q: The following is the equilibrium diagram for two compounds A and B, each has a melting point of 80…
A: Eutectic Point: The Point, where the liquidus curves and solidus intersect, is termed the eutectic…
Q: BRIEFLY explain why steam distillation can be used to purify or isolate temperature-sensitive…
A: A question based on analytical separation that is to be accomplished.
Q: You were given a mixture of four liquid compounds A, B, C, and D. When performing a gas…
A: The data for the gas chromatography experiment were given as A =1.378 mins, B =0.621 mins, C = 1.943…
Q: Is the unknown compound considered pure? Choose... Explain your answer. Normal BIIIU X2 | X² | → fx…
A: Melting point analysis provides information about purity of sample .A pure substance with impurities…
One equipment melts a chemical at 121–122°C whereas another melts it at 129–130°C. Sadly, neither device is calibrated. How can you identify your sample without calibrating either instrument?
Step by step
Solved in 2 steps
- Oral rehydration salts are stated to contain the following components: Sodium Chloride 3.5g Potassium Chloride 1.5g Sodium Citrate 2.9g Anhydrous Glucose 20.0g 8.342 g of oral rehydration salts are dissolved in 500 ml of water. 5 ml of the solution is diluted to 100 ml and then 5 ml is taken from the diluted sample and is diluted to 100 ml. The sodium content of the sample is then determined by flame photometry. The sodium salts used to prepare the mixture were: Trisodium citrate hydrate (C6H5Na3O7, 2H2O) MW 294.1 and sodium chloride (NaCl) NW 58.5. Atomic weight of Na = 23. The content of Na in the diluted sample was determined to be 0.3210 mg/100 ml. Determine the % of stated content of Na in the sample. The stated should be 104.5, how??Oral rehydration salts are stated to contain the following components: Sodium Chloride 3.5g Potassium Chloride 1.5g Sodium Citrate 2.9g Anhydrous Glucose 20.0g 8.342 g of oral rehydration salts are dissolved in 500 ml of water. 5 ml of the solution is diluted to 100 ml and then 5 ml is taken from the diluted sample and is diluted to 100 ml. The sodium content of the sample is then determined by flame photometry. The sodium salts used to prepare the mixture were: Trisodium citrate hydrate (C6H5Na3O7, 2H2O) MW 294.1 and sodium chloride (NaCl) NW 58.5. Atomic weight of Na = 23. The content of Na in the diluted sample was determined to be 0.3210 mg/100 ml. Determine the % of stated content of Na in the sample.State TWO benefits of the mobile phase being prepared by the instrument rather than having to be prepared manually by the lab technician.
- Please answer Questions 5-3, 5-4, and 5-5 (GC Gas Chromatography) 5-2. A sample mixture of ethyl benzoate (bp 212 Celsius) and dodecane (bp 216.2 Celsius) is injected on two GC columns.Column A has DC710 silicone oil as the stationary phase, and column B uses polyethylene glycol as the stationaryphase. Which substance would be certain to elute first from column A and would the same material be expected toelute first from column B? Which column, A or B, would be expected to give the better separation of these two substances? 5-3. Question 5-2 refers to separating a mixture of two high boiling liquids by gas chromatography. These materials havesimilar boiling points. List several GC variables and conditions that would make it easier to separate thesesubstances by gas chromatography. 5-4. Capillary GC columns have better resolution than packed columns even though the enormous surface area provided by the packing material is absent in capillary columns. Why? 5-5. Preparative GC requires…Figure 1 shows normal calibration of benzene, meanwhile Figure 2 shows calibration of benzene using internal standard method. a) State TWO (2) differences between those two calibration curves. b) State THREE (3) limitations of internal standardization method in analytical chemistry.Enumerate and describe the signs of emulsion instability. At least 5-7
- Describe the different types of GC instrumentation and column types available, and provide some of the pro’s and con’s of each particular type for pharmaceutical and forensic analysis.1a) Hexane, CH3(CH2)4CH3, is found to have a long retention time when separated from a mixture. A column with a C18 (18-carbon chain) stationary phase and a methanol-water modal phase is used for the separation. Explain why hexane has a long retention time. 1b)You wish to chromatographically seperate a mixtureof the follwing compunds. Which of the two compounds will be most difficult to seperatate from one another? Why?Column length: 25.0 cm Column diameter: 0.46 cm Stationary phase: C-18 Mobile phase: 80% methanol in water Flow rate: 1.0 mL/min Dead time: 5 min Peak width at base, WA = 20 Peak width at base, WB = 24
- Pesticide residues were found in a lot of oranges; the compound identified was the epoxide of heptachlor (EH). To quantify the amount of this pesticide in oranges, 20 grams were taken from fruit peels and mixed with methylene chloride to extract it. The concentration of heptachlor epoxide in the sample was determined by gas chromatography coupled to a detector mass (GC-MS); and calibration was performed using anthracene (A) as internal standard. For In this analysis, the anthracene had a concentration of 350 ppm and the same volume was added to each standard. The table below shows the concentrations of the standard and the ratio of the areas.and the sample is: 0.1080.Determine the concentration of heptachlor epoxide in the sample.A mixture of three components is separated using paper chromatography, and each component is analyzed using absorption. With standards containing 100 ppm of each component run simultaneously, the following data were obtained: cmpd A, 0.72 absorbance; B, 0.55; C, 0.80. For the unknown mixture, the data obtined when run under identical conditions were as follows: cmpd A, 0.15 absorbance, B, 0.84; C, 0.75. a) Calculate the relative percentage composition of the unknown mixture. b) The distances traveled by the three components were 8.5, 6.3, and 5.5 cm, respectively. Sketch the appearance of the paper chromatogram. Label each spot. c) Calculate the Rf values if the solvent front is 18 cm.Based on the different chromatographic techniques that you have learned, provide a method or describe a procedure how to analyse the following samples: 1. Analysis of dioxin in water by gas-chromatography 2. Analysis of parabens in cosmetic product by gas chromatography 3. Analysis of caffeine in beverage by HPLC 4. Analysis of PCB in water by HPLC
