Hi, I have a question on Gas Chromatography(GC). The following were injected into the GC system: - 1) 1% sample solution in acetone 2) a 500 times dilution of item 1) The retention time of the main peak in the

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  1. Science

    Hormones and Homeostasis 1) The human endocrine system is made up of which of the following structures? :Vessels. :Receptors. :Glands.*** :Chambers. 2. Which of the following best describes the function of the endocrine system? :It secretes chemical

  2. Science The Human Body PLEASE HELP!!!!!!!!!!!

    the human endocrine system is made up of which of the following structures? (1 point) vessels receptors* glands chambers 2. Which of the following best describes the function of the endocrine system? (1 point) It secretes chemical messengers that travel

  3. Chemistry

    A 108 mL gas sample has a mass of 77.96 mg at a pressure of 1140 mmHg and a temperature of 183 °C. Assume ideal gas behavior and a completely insulated system, and please don’t forget units with your answers. The system is cooled. Calculate the

  4. (2-8) Chemistry - Science (Dr. Bob222)

    Which of the following statements is correct? A) The internal energy of a system increases when more work is done by the system than the heat that flows into the system. B) The system does work on the surroundings when an ideal gas expands against a

  5. chemistry

    6.0mol of ammonia gas is injected into a 3.0 mol L container. at equilibrium 1.5 mol of hydrogen gas is found in the container. the number of moles of ammonia gas left in the container must be which of the following?

  6. Chemistry

    10.0 mol of ammonia gas is injected into a 4.0 L container. At equilibrium 1.2 mol of nitrogen gas is found in the container. The number of moles of ammonia gas left in the container must be which of the following? N2(g) + 3H2(g) 2NH3(g) + 94 kJ a. 8.8 d.

  7. Chemistry

    What method of separation would you use for the following mixtures: acetone and water aluminum powder and ethyl alcohol. these were questions asked after a chapter of reading in my chem book. the separation techniques listed in the reading are filtration,

  8. Science

    Which of the following is true about diabetes? A. The pancreas overproduced glucose, and so insulin must be injected to reduce glucose levels. B. The pancreas underproduced glucose, and so insulin must be injected to increase glucose levels C. The pancreas

  9. Chemistry

    Study the reaction. H2SO4(l) + CaCO3(s) ⇌ CO2(g) + H2O(l) + CaSO4(aq) Which of the following would cause the equilibrium to shift, producing more carbon dioxide gas? Select all that apply. removing water from the system removing H2SO4 from the system

  10. chemistry

    A common laboratory system to study Boyle's law uses a gas trapped in a syringe. The pressure in the system is changed by adding or removing identical weights on the plunger. The original gs volume is 50.0 ml when two weights are present. Predict the new

  11. Chemistry

    9.0 moles of pure ammonia gas were injected into a 3.0 L flask and allowed to reach equilibrium according to the equation shown below. If the equilibrium mixture was analyzed and found to contain 3.0 moles of hydrogen gas, calculate the value of the

  12. Science Plzz Help

    . Which of the following is true about diabetes? A. The pancreas overproduces glucose, and so insulin must be injected to reduce glucose levels. B. The pancreas underproduces glucose, and so insulin must be injected to increase glucose levels. C. The

  13. biology

    5. A researcher finds that blood alcohol levels cause progressive damage to the liver. All the mice in his study were fed the same amount and types of food. Different concentrations of alcohol were injected into each mouse. One group of mice does not

  14. Organic Chemistry Lab

    A sample of hexane and octane is injected into a gas chromatograph equipped with a nonpolar column. Predict which one will have the shorter retention time.

  15. Mobility and Rf

    We did a column chromatography then a TLC on extracted spinach pigments. Question: Why are the chlorophylls less mobile on column chromatography and why do they have lower Rf values than the carotenes? My answer: The chlorophylls are more polar than the

  16. chemistry

    which of the following steps in the formation of KCI releases energy? A.K{solid} -> K{gas} B.K {GAS} -> K+ {GAS} + e- C.C1 {GAS} -> C1- {GAS} D.C1 {GAS} + e- -> C1 - {GAS} E. K+ {GAS} + C1- {GAS} -> KC1 {SOILD} A. A B. C C. B AND A D. D AND E I will be

  17. language

    1.which factor is most helpful in helping technology to progress? a) unintended consequences b) a better understanding of the natural world c) risk-benefit analysis d)obsolete technologies 2. an oven is a technological system. which of the following

  18. Chem Check Please!

    What type(s) of chromatography is/are most appropriate for solids? Explain ----Liquid-Solid Chromatography ----Thin-Layer Chromatograph What type(s) of chromatography is/are most appropriate for liquids? Explain ----High performance liquid chromatograpy

  19. Science Ms. Sue Please

    1. The human endocrine system is made up of which of the following structures? (1 point) vessels receptors glands * chambers 2. Which of the following best describes the function of the endocrine system? (1 point) It secretes chemical messengers that

  20. science

    The diagram below represents a phase change. Which of the following best describes what is happening in the diagram? A. A liquid is changing into a gas because pressure in the system is increasing. B. A gas is changing into a liquid because thermal energy

  21. organic chem

    How do injector temperature and detector temperature affect retention time of a compound in gas chromatography?

  22. list of rf values

    can you give a comprehensive list of rf values. rf: Radio Frequency? I am uncertain what the context of rf is. rf probably is related to chromatography. They are the retention factors for thin layer chromatography; i.e., TLC. I looked on www.google.com an

  23. Science!

    An oven is a technological system. Which of the following describes an input into this system? A. Setting the temperature B. Burning gas releases heat. C. A thermostat monitors the temperature and increases the gas flow when the temperature falls too low.

  24. chemistry

    Question: Consider this molecular-level representation of a gas. There are: 5 orange gas particles 6 blue gas particles 3 green molecules of gas (two particles attached together) If the partial pressure of the diatomic gas is 0.510 atm, what is the total

  25. Science Plzz Help

    4. Which of the following is true about diabetes? A. The pancreas overproduces glucose, and so insulin must be injected to reduce glucose levels. B. The pancreas underproduces glucose, and so insulin must be injected to increase glucose levels. C. The

  26. chem

    6.01-L cylinder contains 1.25 mol of gas A and 4.54 mol of gas B, at a temperature of 32.8 °C. Calculate the partial pressure of each gas in the cylinder. Assume ideal gas I have work this question three time and can not get the rt answer

  27. Chemistry

    I conducted a Gas Chromatography experiment using Flame Ionisation Detector (FID).A capillary column was used. 1)Blank 2) Standard 3) Sample 4)Blank 5)Standard The above was injected into the system. In 2)Standard chromatogram,a sharp, thin peak was

  28. organic chemistry

    How can gas chromatography determine what mechanism a reaction underwent? For example, I was to synthesize an alkyl halide using 1-propanol, NaBr, and sulfuric acid. I know its a substitution reaction, but how can gas chromatography tell me whether its SN1

  29. Chemistry-help

    Hi, I have a question on Gas Chromatography(GC). The following were injected into the GC system: - 1) 1% sample solution in acetone 2) a 500 times dilution of item 1) The retention time of the main peak in the diluted sample solution 2) shifted by ~ 2min.

  30. Chemistry

    Two flasks containing the same inert gas are at the same temperature and pressure of 800. mm Hg. One flask is injected into each of the flasks to allow phase equilibrium to be established. No leakage occurs. If the pressure in the 1.0 L flask is 900 mm Hg,

  31. Chemistry

    What is the mobile phase in this experiment? A) 10% 6M NaOH and 90% acetone B) 10% 6M HCl and 90% acetone C) 10% 5M KCl and 90% methanol D) 10% 5M KCl and 90% acetone Gel electrophoresis is an example of which type of chromatography? A) Column

  32. organic chemistry

    in gas chromatography, why do E1 and E2 give different peaks (areas) though it's the same compound?? dehydration of a secondary alcohol proceeds readily with the presence of strong acid and proceeds with E1 mechanisms. Removing product from chemical system

  33. Bioanalytical Chemistry

    Considering size-exclusion chromatography, ion-exchange chromatography, reversed-phase liquid chromatography, and capillary electrophoresis list the possible combinations (there are a total of 6) of techniques that could be coupled to give a 2-dimensional

  34. Chemistry

    Which method(High Performance Liquid Chromatography or Gas Liquid Chromatography) would be suitable for the separation of the following mixtures? 1) Mixture of paracetamol, codeine and caffeine. 2) Mixture of alpha-pinene, beta-pinene, eucalyptol,

  35. forensic science

    What type of substance is the mobile phase in gas chromatography? a polar liquid a nonpolar liquid a mixture of two liquids to create the correct polarity a polar gas an inert gas like nitrogen my answer is an insert gas like nitrogen

  36. Chemistry

    The maximum number of PbO molecules that can be injected is 3.01 x 10*23 1.) How many moles of PbO can be injected? 2.) What mass of PbO can be injected?

  37. algebra 2

    A nurse must careful not to inject a drug too quickly into a patient's IV. If the drug is injected at maximum rate of 0.04cc per second, and the total amount to be injected is 25cc. create an equation that tells the amount injected as a function of time in

  38. Chemistry-please help

    Hi, I have a queestion on Gas Chromatography(GC). The following were injected into the GC systemk: - 1) 1% sample solution in acetone 2) a 500 times dilution of item 1) The retention time of the main peak in the diluted sample solution 2) shifted by ~

  39. chemistry

    How is column chromatography and planar chromatography methods are performed?

  40. Chemistry

    Nitrogen and hydrogen, with volumes of 12.0 L each, are injected into a sealed rigid reaction chamber containing a catalyst. The pressure of the chamber is 8.00 atmospheres and at a known temperature. The reaction is allowed to proceed to completion while

  41. chem

    What would be the effect of raising the temperature and increasing the carrier gas flow rate on the ability to resolve two closely spaced peaks in gas chromatography? -I was thinking that the width or the maximum peak of each curve will change since the

  42. Science

    1. The human endocrine system is made up of which of the following structures? (1 point) vessels receptors glands * chambers 2. Which of the following best describes the function of the endocrine system? (1 point) It secretes chemical messengers that

  43. chemistry

    A compressed gas cylinder of H2 containing 25 l at 200,000 kPa of pressure is emptied due a leak in a gas chromatography laboratory, with the following dimensions: 5 m long, 4 meters wide and 2.5 m height. Calculate the % oxygen and hydrogen in the

  44. Math help plz

    The human endocrine system is made up of which of the following structures? (1 point) vessels receptors glands chambers 2. Which of the following best describes the function of the endocrine system? (1 point) It secretes chemical messengers that travel

  45. Organic Chem

    What factors affect the rate of travel of compounds in the Gas Chromatography column?

  46. Chemistry (lab)

    What are the units of retention time in gas liquid chromatography? Minutes or seconds?

  47. Chemistry

    What is the function of Compressed Air in GC-FID (i.e. Gas Chromatography-Flame Ionization Detector)?

  48. Chemistry

    I am trying to study for my chem test but I don't get how to answe this question A researcher explores the ideal gas equation. He measures the pressure of a system at different temperatures ( keeping the volume and moles of the gas constant) and creates a

  49. science

    in gas chromatography, if the two peaks in chromatogram are too close, what changes in experimental conditions could make to separate them more effectively?

  50. Chemistry

    In gas chromatography, what would be the order of the retention times for your mixture (hexane and toluene)? What is the basis for your answer?

  51. organic chemistry

    in gas chromatography, why do E1 and E2 give different peaks (areas) though it's the same compound?? For example, for 1-butene, the percent composition is low in E1 but very high in E2.

  52. chemistry

    When 1.0 mol of ammonia gas in injected into a o.50L flask, the following reaction proceeds to equilibrium. 2NH3 N2 (g) + 3H2 (g) At equilibrium, 0.30 mol of hydrogen gas is present. a) calculate the equilibrium concentrations of N2 and Nh3. b) what is the

  53. Science

    Which of the following is true about diabetes? A. The pancreas overproduced glucose, and so insulin must be injected to reduce glucose levels. B. The pancreas underproduced glucose, and so insulin must be injected to increase glucose levels C. The pancreas

  54. chemistry

    a sample of hexane and octane is injected into a gas chromatograph equipped with a non-polar column. predict which will have the shorter retention time

  55. chemistry

    What will be the effect on a chromatogram of two well separated peaks if: (this is for a gas chromatography) a) the carrier gas flow is set too high? b) the temperature of the injection port is set too low? c) the temperature of the column is set too high?

  56. Chemistry

    What will be the effect on a chromatogram of two well separated peaks if: (this is for a gas chromatography) a) the carrier gas flow is set too high? b) the temperature of the injection port is set too low? c) the temperature of the column is set too high?

  57. Bioanalytical Chemistry

    Compare and contrast Ion-exchange Chromatography and Immobilized-metal Affinity Chromatography by considering the following: separation mechanism, effect of ionic strength, effect of pH, groups bound to stationary phase, and elution solutions.

  58. chemistry

    Consider a system consisting of a cylinder with a movable piston containing 10^6 gas molecules at 298K at a volume of 1L. Consider the following descriptions of this system: 1. Initial system 2. Starting from the initial system, the volume of the container

  59. chemistry

    Consider a system consisting of a cylinder with a movable piston containing 10^6 gas molecules at 298K at a volume of 1L. Consider the following descriptions of this system: 1. Initial system 2. Starting from the initial system, the volume of the container

  60. Chemistry

    Two Flasks containing the same inert gas are at the same temperature and pressure of 800 mmHg. One flask has volume of 1.0 L and the other, a volume of 2.0 L. Enough volatile liquid is injected into each of the flasks to allow phase equilibrium to be

  61. Grammar

    1.She is a nurse with who / whom I enjoy working. A) who B) whom 2.Then 50 cc of Marcaine was / were injected. A) was B) were 3.Then 50 cc of Marcaine was / were injected. A) was B) were My answers: 1.b 2.a 3.b

  62. Chemisrty

    Identify the type of question. Is it a literature research question, observation only question, demonstration question, or investigation question? How would you determine the PH of vinegar using cabbage juice as an indicator? (investigation) Do germaniting

  63. science(chem)

    How do I analyze a HPLC result? The lab tech injected the sample into the machine and I have the result paper for the sample injected which was caraway oil. However I'm not sure what to do with this now. It was recorded in volts per minutes. Thanks

  64. Physics

    Damon, this is my last question for today for you. Thanks for all your help. A gas is at an initial pressure of 1.24104 Pa and occupies a volume of 0.28 m3. The (slow) addition of 23,570 cal of heat to the system causes it to expand in an isobaric manner

  65. chemistry

    1. In standard column chromatography, it is better to change from a nonpolar solvent to more polar solvent. What are some disadvantages if the reverse is done? 2. what would happen if air bubbles were trapped in the adsorbent in column chromatography? is

  66. Chemistry

    Why is a Gas Chromatography separation more efficient than a fractional distillation? What characteristics must the liquid stationary phase have? describe a method for identifying a compound using GC analysis. If you could answer anyone of these that would

  67. Chem Home Work Help!

    I am a bit confuse with a question from a home work that I need to do by today please help! HW question... 1) A sample of neon gas occupies 8.77 L at 20°C. What is the pressure, in atmospheres, exerted by 1.45 mol of this gas? When you've gotten the

  68. Biology

    I'm learning about chromatography and photosynthetic pigments. My question is "how can we measure the light absoptive characteristics for a leaf extract?"

  69. chemistry

    at 22°C the equilibrium constant, Kc, for the following reaction is 4.66 x 10-3. (1) If 0.800 mol of N2O4 were injected into a closed 1.00-L container at 22°C, how many moles of each gas would be present at equilibrium? (b) If the volume were halved (to

  70. Chemistry

    Okay, I know I asked this before (a while ago), except I lost the link to my original question and the answer to it... What property of liquids and solids is crucial in chromatography?

  71. chemistry

    I would really like help for this question ASAP! pleasee! I thank you ahead of time. The question refers to an experiment using equal volumes of O2 gas and three other gases "X", "Y", "Z", at the same temperature and pressure. If the respective masses are:

  72. chemistry

    I would really like help for this question ASAP! pleasee! I thank you ahead of time. The question refers to an experiment using equal volumes of O2 gas and three other gases "X", "Y", "Z", at the same temperature and pressure. If the respective masses are:

  73. help on a question

    I needed help on a physical science question. When the molecules in a body move with increased speed, it's possible that the body will change from a... A) gas to a liquid B) gas to a solid C) liquid to a solid D) liquid to a gas PLEASE HELP ME!! If the

  74. college phyics

    A system consists of 3.2 mol of the monatomic gas neon (which may be treated as an ideal gas). Initially the system has a temperature of 290 K and a volume of 1.2 m3. Heat is added to this system at constant pressure until the volume triples, then more

  75. science

    A university student wants to perform an experiment using mice as test subjects. The procedure would require the mice to be injected with a specific bacterial infection and then treated with an antibiotic. Their response to the treatment would be observed

  76. science

    A university student wants to perform an experiment using mice as test subjects. The procedure would require the mice to be injected with a specific bacterial infection and then treated with an antibiotic. Their response to the treatment would be observed

  77. Math

    A study investigated whether injecting mice with a certain hormone would affect the time it takes them to learn a task. Learning times of 12 mice with the hormone injected were compared with those of 12 mice without the hormone injected. The mean of the

  78. precalculus

    A study investigated whether injecting mice with a certain hormone would affect the time it takes them to learn a task. Learning times of 12 mice with the hormone injected were compared with those of 12 mice without the hormone injected. The mean of the

  79. Math

    A study investigated whether injecting mice with a certain hormone would affect the time it takes them to learn a task. Learning times of 12 mice with the hormone injected were compared with those of 12 mice without the hormone injected. The mean of the

  80. Physics repost for Dejanae

    (Please use Ask a New Question instead of piggybacking on another student's question.) a system does 300 j of work at the same time that 1000 j of energy is transferred to the system as heat whats is the change in the system's internal energy

  81. Health

    what are the different ways stimulants can enter the body? & is it possbile for certain stimulants to be injected (like by a needle)into the body? & if so what kind of stimulants are injected?

  82. chrmistry

    Can someone explain me this question: What assumption must we make about the dissolving of a gas in water for the solubility evidence to be valid? what does the question really wants to ask??? I mean is it the observations when the gas dissolves in the

  83. biology

    1. name an organism in which the respiratory and circulatory systems are separate. 2. name an organism with a closed circulatory system that is not used for gas exchange. 3. name an organism whose waste gases accumulate in one system but then move to

  84. physics

    Question 01: 2.0g of Nitrogen gas is at 270C in a fixed volume. If 20% of its total internal energy is due to rotation what is the average velocity of nitrogen molecules? What will be the temperature 2.0 g of Helium gas in a fixed volume if the average

  85. chemistry

    QUESTION 11 Ammonia gas is formed from nitrogen gas and hydrogen gas, according to the following equation: N2 (g) + 3H2 (g) Imported Asset 2NH3 (g). If 84.0 g of nitrogen gas is allowed to react with an excess of hydrogen gas to produce 85.0 g of ammonia,

  86. Chemistry

    (a) What type of ion chromatography (cation or anion) will you use to separate the following ions: Cu2+, Fe3+, Ag+ and Na+ . I'm having trouble here as I know that in elution chromatography they use like charges to separate ions, but is that the same case

  87. chemistry

    An enzymatic method for determining alcohol in wine is evaluated by comparison with a gas-chromatography (GC) method. the same sample is analyzed several times by both methods with the following results (% ethanol). Enzymatic method:

  88. Chemistry

    If the gas chromatograph is polar, and a mixture of a polar compound and a non-polar compound is injected. Which one of the two compounds will have a higher retention time? Why?

  89. college chem

    A researcher explores the ideal gas equation. He measures the pressure of a system at different temperatures ( keeping the volume and moles of the gas constant) and creates a plot of P versus T. What is the slope of the line that results if the volume is

  90. chem

    6.01-L cylinder contains 1.25 mol of gas A and 4.54 mol of gas B, at a temperature of 32.8 °C. Calculate the partial pressure of each gas in the cylinder. Assume ideal gas I have work this question three time and can not get the rt answer

  91. physics

    Consider 3 liters of an ideal (monatomic) gas at a pressure of 34 atm and a temperature of 356K. Call this state of the system A. Using the ideal gas law, calculate the number of moles of gas present in the system. 3.49 The temperature of the system is

  92. chemistry

    QUESTION 10 Ammonia gas is formed from nitrogen gas and hydrogen gas according to the following equation: N2 (g) + 3H2 (g) Imported Asset 2NH3 (g). If 112 grams of nitrogen gas is allowed to react with an excess of hydrogen gas to produce 120 grams of

  93. physics

    Ok, so I know I already posted another really long question but we have not learned this yet and are expected to do homework on it. Please help me. An ideal monotonic gas is compressed at a constant pressure of 0.9 atm from 14 L to 3.5 L. Note: Atmospheric

  94. Physics

    If ∆Q is the heat supplied to a gas so that the internal energy of the system increases by ∆U, then the work done ∆W by the gas is equal to: ∆Q – ∆U ∆Q + ∆U ∆Q x ∆U ∆U/∆Q

  95. TLC

    The following two solvents systems were found to separate compounds x and y by flash column chromatography: X- hexanes/ethyl acetate 10:1 Y- hexanes/ethyl acetate 10:4 which is more polar X or Y? Which solvent system must be used first?

  96. Physics Urgent

    A container of volume V = 103 cm3 has a mass of 30.0042 g when evacuated. When the container is filed with an unknown gas of pressure p = 4.72 atm at temperature T = 20oC, the mass of the system increases to 30.9508 g. Assuming that the unknown gas behaves

  97. Physics Urgent

    A container of volume V = 103 cm3 has a mass of 30.0042 g when evacuated. When the container is filed with an unknown gas of pressure p = 4.72 atm at temperature T = 20oC, the mass of the system increases to 30.9508 g. Assuming that the unknown gas behaves

  98. Chem

    A researcher explores the ideal gas equation. He measures the pressure of a system at different temperatures ( keeping the volume and moles of the gas constant) and creates a plot of P versus T. What is the slope of the line that results if the volume is

  99. Urgent need help on chem please someone

    A researcher explores the ideal gas equation. He measures the pressure of a system at different temperatures ( keeping the volume and moles of the gas constant) and creates a plot of P versus T. What is the slope of the line that results if the volume is

  100. statistics

    If the probability of running out of gas is .03 and the probability the electronic starting system will not work is .01 a.) what is the probability there will be enough gas and that the starting system will work? assume the two events are independent b.)

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