1. ANALYTICAL CHEMISTRY

    A sample weighing 1.25 mg containing a certain compound M (FW 292.16 g/mol) was dissolved in solvent in a 5.00 mL volumetric flask. A 1.00 mL aliquot was drawn up, placed in a 10.00 mL volumetric and diluted to the mark with solvent. The absorbance of this
  2. science

    A sample weighing 1.25 mg containing a certain compound M (FW 292.16 g/mol) was dissolved in solvent in a 5.00 mL volumetric flask. A 1.00 mL aliquot was drawn up, placed in a 10.00 mL volumetric and diluted to the mark with solvent. The absorbance of this
  3. Chemistry

    Use the following information to identify element A and come pound B, then answer questions a and b. An empty glass container has a mass of 658.572 g. It has a mass of 659.452 g after it has been filled with nitrogen gas at a pressure of 790. torr and a
  4. grammar

    Indentify each sentence as simple, compound, complex, or compound-complex. Could you tell me if my answers are correct please? 1. In 1942, the United States Navy sank four Japanese aircraft carriers; moreover, the United States Army Air Force joined
  5. chem

    A 0.01020 mg sample of an unknown compound was found to contain 0.0084 mg of C, and 0.0018 mg of H. It was also determined that the unknown compound had a molecular weight of 58.12 g/mol. What is the molecular formula for this compound?
  6. Chemistry

    For the gas phase decomposition of chloroethane, CH3CH2Cl C2H4 + HCl the rate constant at 723 K is 1.75E-4 /s and the rate constant at 769 K is 2.19E-3 /s. The activation energy for the gas phase decomposition of chloroethane is
  7. science

    Chemistry Hey guys, i have a question about how to figure out how much mass of a compound i need to find 130ppm here is the question. What mass of Fe(NH4)2(SO4)2*6H2O is required to prepare 2.25 L of a 130 ppm iron solution? Now i know that ppm is (mg of
  8. Chemistry Help Please!

    1) You are going to make 1800ml of a 25uM solution using a compound whose MW= 60.06 Daltons. How many grams do you need of this compound? Give your answer with four decimal places. 2) You are going to make 300ml of a 75mM solution using a compound whose
  9. Biology Help Please!

    1) You are going to make 1800ml of a 25uM solution using a compound whose MW= 60.06 Daltons. How many grams do you need of this compound? Give your answer with four decimal places. 2) You are going to make 300ml of a 75mM solution using a compound whose
  10. chemistry

    what type of reaction is Nickel (II) ion and iron (III) ion and reacts to produce iron (II) and nickel (III) ions? is it: combination, decomposition, single or double replacement.
  11. Chemistry

    How do you find the empirical formula; A 4.083 sample of a chemical containing only lead, carbon, and hydrogen reacts in combustion reaction. 4.444 g of CO2 and 2.274 g of H2O were formed. Insert subscripts in CHPb. I understand how to find moles, then
  12. Chemistry

    A 0.08425 g sample of gas occupies 10.0-mL at 292.5 K and 1.10 atm. Upon further analysis, the compound is found to be 13.068% C and 86.932% Br. What is the molecular formula of the compound? Identify the geometry around each carbon atom. a)trigonal
  13. Chem

    a 0.2000 grams sample of aluminum metal is added to a solution containing 1.0000grams of an unknown compound made of platinum and chloride ion. the reaction results in the formation of aluminum chloride and platinum metal. when the reaction is complete,
  14. chemistry

    The decomposition of potassium chlorate, KClO3, gives oxygen gas and solid potassium chloride. How many grams of KClO3 are needed to produce 5.00 L of Oxygen gas at STP? Suppose that the reaction described above produces 4.80 L of O2 in the laboratory.
  15. chemistry

    How much does 1 molecule of bromine weigh? I know the atomic mass for bromine is 79.90 g but I do not know how to use it to figure out the weight of the molecule. The given answer is 2.654x10^-22 but I do not know how to get there. First, the molecule of
  16. chemistry

    Which statement describes a chemical reaction at equilibrium? A. The forward reaction happens slightly faster than the reverse reaction. B. The reaction has stopped because all reactants have been used up. C. The forward reaction happens at the same rate
  17. chemistry

    The solubility of an ionic compound is 30 grams of compound in 100 mililiters of water. If 60 grams of the compound is dissolved in 200 mL of water, the solution will saturated. t/f
  18. Chemistry

    Please write the balanced chemical equation for reaction the following chemical reaction ozone gas, O3, reacts with 3,3,4,4,5,5-hexanmethyl-1-hexyne, H-C≡C-C(CH3)2-C(CH3)2-C(CH3)2-CH3 to produce carbon dioxide gas, CO2 , and water gas, H2O When balancing
  19. Chemistry- Kinetics

    2. At 600 K the decomposition of gas ohase nitroethane (CH3CH2NO2) is first order with a rate constant of 1.9*10^-4 s^-1. CH3CH2NO2 --> C2H4 + HNO2 a) Write out the differential and integrated rate laws for this reaction. b) If a 10.0g sample of
  20. chemistry

    In the presence of a tungsten catalyst at high temperature, the decomposition of ammonia to nitrogen and hydrogen is a zero order process. If the rate constant at a particular temperature us 3.7x10^-6 mol. How long will it take for an ammonia concentration
  21. Chemistry

    Consider the following decomposition reaction of ammonium carbonate ((NH4)2CO3): (NH4)2CO3 (s)  2 NH3 (g) + CO2 (g) + H2O (g) In one experiment at 25.0°C, a sample of pure (NH4)2CO3 is placed in an evacuated 2.00 L vessel. At equilibrium, the total
  22. chemistry

    The thermal decomposition of calcium carbonate produces 2 by-products, c02 and calcium oxide. calculate the volume of the co2 produced at STP from the decomposition of 231 grams of caco3. i know the equation i need to use is V=nrt/p but am i supposed to
  23. appl,ied business research & statistics

    When would you use Chebyshev’s theorem and the empirical rule in health administration? How are they calculated? Provide one real-life example that requires Chebyshev’s theorem and one that requires the empirical rule.
  24. chem-help

    Use the following information to identify element A and come pound B, then answer questions a and b. An empty glass container has a mass of 658.572 g. It has a mass of 659.452 g after it has been filled with nitrogen gas at a pressure of 790. torr and a
  25. Chemistry help

    Hello. Can I get someone to help me set up these problems? 1.) How many moles of N are there in 2.6 moles of NHO3? 2.) How many moles of C2H6 (g) are consumed when 4.4 mol CO2 (g) are produced? 3) How many milliliters of 0.80 M CuSO4 must be diluted to
  26. Grammar

    Label each sentence below as simple, compound, complex, or compound-complex. 1. You can enter the data, or you can interview the candidates. (compound) 2. No one knew the man, and no one asked his name. (compound) 3. After the officer pulled Tim over, Tim
  27. Chem

    If the initial pressure of HD(g) is 8.913 atm, calculate the % decomposition of HD(g) when the reaction comes to equilibrium according to the balanced equation. The value of Kp at 1000 K is 0.26. The initial pressure of the reaction products is 0 atm.
  28. Organic Chem

    A LITTLE CONFUSED...QUESTION ASKS THE REAGENT SHOWN IS ADDED TO THE COMPOUND, WHAT SHOULD YOU SEE WHEN THE TWO MATERIALS ARE MIXED TOGETHER? IS THE ANSWER THE PRODUCT OR THE REACTION, LIKE HEAT OR COLOR CHANGE. AND IF ITS PRODUCT IM CONFUSED? PLEASE HELP.
  29. English

    Which of the following is a simple sentence? A. Many are called, but few are chosen B. A penny saved is a penny earned C. Fools rush in where angels fear to tread D. If at first you don’t succeed, try, try again 2. Which of the following is a compound
  30. chemistry

    two everyday chemical reactions then after you have chosen your two everyday chemical reactions List the two reactions and their chemical equations. Also, state each reaction's type (synthesis, decomposition, displacement, or combustion). please help
  31. chemistry

    what is the geometry of the molecular compound formed by the reaction of sulfur with hydrogen? linear angular trigonal planar tetrahedral please explain the correct answer
  32. AP Chemistry

    I need alot of help on this problem, it is due WEDNESDAY and I have no clue how to do it Use the following information to identify element A and come pound B, then answer questions a and b. An empty glass container has a mass of 658.572 g. It has a mass of
  33. AP CHEM FULL ?

    This is part of a marathon problem, we have to identify the five compunds of H, N, and O described below. For each compound, I have to write a Lewis structure that is consistent with the information given. a.) All the compunds are electrolytes, although
  34. Chemistry

    The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [IBr] to go from 0.500M to 0.100M? (c)What
  35. soc 300

    Explain the Modernization and Dependency theories as they relate to underdevelopment. What are the major contributions of each theory and what are the greatest weaknesses? Explain which theory of underdevelopment has greater empirical support, particularly
  36. (11) Chemistry - Science (Dr. Bob222)

    In the following hypothetical reaction A + B → C + D, the equilibrium constant, Keq is less than 1.0 at 25°C and decreases by 35% on changing the temperature to 45°C. What must be true according to this information? A. The ΔH° for the reaction is
  37. Science

    For carbon to move from an animal to a car, what processes need to happen? Photosynthesis, combustion, and respiration? Respiration, fossilization, and photosynthesis? Fossilization, decomposition, and respiration? Or respiration, photosynthesis, and
  38. Science

    For carbon to move from an animal to a car, what processes need to happen? Photosynthesis, combustion, and respiration? Respiration, fossilization, and photosynthesis? Fossilization, decomposition, and respiration? Or respiration, photosynthesis, and
  39. English

    Consider the compound words blackboard and outfox and the relationship of their meanings to the meanings of the words that make them up. In what ways do these compound words show a degree of nonarbitrariness in their form-meaning connection? Will this true
  40. Chemistry

    At room temperature (25 °C), the gas ClNO is impure because it decomposes slightly according to the equation 2ClNO(g) Cl2(g) + 2NO(g) The extent of decomposition is about 4%. Based upon this, what is the approximate value of ΔG°298 for the reaction at
  41. Chemistry

    The gas phase decomposition of dinitrogen pentoxide at 335 K N2O5(g) 2 NO2(g) + ½ O2(g) is first order in N2O5. During one experiment it was found that when the initial concentration of N2O5 was 0.218 M, the concentration of N2O5 dropped to 2.96E-2 M
  42. chemistry

    I need help with this lab. Write the equation for the decomposition of the hydrate, CuSO4*XH2O. Mass of crucible and hydrate: 93.000g Mass of crucible and pure salt: 91.196g I need to calculate the following: 1. mass of water in hydrate sample(g) 2. number
  43. Chemistry

    A researcher is studying the decomposition of A as shown by the general reaction below: 2 A(g) 4 B(g) + 2 C(g) Initially, the scientist fills an evacuated 1.772 L flask with 3.710 x 10-1 moles of species A. Upon equilibrium, it is determined that the
  44. Chemistry

    The lab we are doing is: Determining the ENTHALPY of a Chemical Reaction. There are three reactions. Reaction 1: NaOH + HCl, Reaction 2: NaOH + NH4Cl, and Reaction 3: HCl + NH3. I found the max temp, initial temp, and temp change of each reaction. Can you
  45. chemistry

    In class, we did a decomposition reaction of sodium hydrogen carbonate, which makes water, carbon dioxide, and sodium carbonate. How do you know when sodium hydrogen carbonate is completely reacted?
  46. chemistry

    The combustion of a compound CxHyOz yields CO2 + H2O; all of th carbon in the CO2 came from the compound, all of the hydrogen in the H2O came from the compound; and all of the oxygen in the H2O came from the compound. The oxygen in the CO2 came from the
  47. chemistry

    Analysis of a compound shows carbon hydrogen and nitrogen present. Each molecule contains one nitrogen atom. A 150. Mg sample of the compound produces 27.4 mg of NH3 in which all the nitrogen comes from the sample. Which of the following is the formula for
  48. grammar simple, compound/complex

    1. We like stories which have unusual endings.
  49. Chemistry

    Ermms just cant get my head around this question kinda bugging me :( Solid Sodium Hydrogen dissolving in water i know its a dissociation reaction but i don't really have an idea where to split the compound.
  50. *th Grade Language Arts Ms. Sue Help

    simple, compound, complex, or compound-complex? 1. Yes, I have a bad case of the flu, and because I need to get well soon, I won’t think about returning to school just yet. compound 2. Because they have been preserved well over time, many ancient scrolls
  51. HELP PLZ

    What determines whether one metal will replace another metal from a compound in a single-replacement reaction?
  52. Science

    What determines whether one metal will replace another metal from a compound in a single-replacement reaction?
  53. Chemistry

    What determines whether one metal will replace another metal from a compound in a single-replacement reaction?
  54. Chemistry

    From the following data, calculate ΔH° for the reaction O3(g) +NO(g)----->O2(g)+NO2 (g) Compound ΔH°f (kJ/mol) O3 142.7 NO 90.3 O2 0 NO2 33.2
  55. Chemistry

    1/2 H2(g) + 1/2 I2(g) -> HI(g) △H= +28kJ The activation energy for the formation of HI is 167kJ. The activation energy for the decomposition of HI is A. 28kJ B.139kJ C.167kJ D.195kJ I know it is an endothermic reaction.
  56. chem

    PLEEEZE help name the type of reaction K + MgBr -> Not enough information is provided. And not magnesium bromide is MgBr2. Is this a solution phase or exactly how is the K metal added to the MgBr2? As DrBob has indicated, not all of the information has
  57. chemistry

    which of the following compounds contains the lowest percentage by mass of nitrogen? 1) NH4NO3 2) (NH4)2 SO4 3) NaNO3 4) NH3 can someone please help me??what method should i use?how do i do this? Find the molar mass of each compound by adding the molar
  58. Chemistry

    Identify any functional groups in compound 1 and 2 COMPOUND 1 CH2 = CH-CH-OH with CH3 under the second CH COMPOUND 2 CH3-CH-CH2-C (double bond O off C and -OH of C) also a CH3 under CH ROH are alcohols. RCOOH are acids.
  59. english

    are both of these a compound or simple sentences I need to have these as a model for the other one's. 1. Her mother went to trade show, but doreen stayed home. 2. Wang and his brother looked at the problem and spotted the solution. i think: 1. compound
  60. chemistry

    (c) some properties of the two compounds are listed below: compound X: compound Y: melting point -144C -138C boiling point 78C -22C net point Yes Yes functional group Alcohol Ether (i.) Draw plausible Lewis Structures of compounds X and Y. (ii.) In which
  61. Chemistry (Help)

    Completion (Help) To find the mass of a mole of a compound, scientists add together the __1____ of the atoms making up the compound. When you substitute the unit grams for amu, you obtain the ____2____ of the compound. There are __3____ representative
  62. AP Chemistry

    The identity of an unknown solid is to be determined. The compound is one of the seven salts in the following table. Al(NO3)3•9H2O BaCl2•2H2O CaCO3 CuSO4•5H2O NaCl BaSO4 Ni(NO3)2•6H2O Use the results of the following observations or laboratory
  63. chemistry

    Compound 1 (Figure 1 below) is a naturally occurring compound produced within the human body. It is carried in the bloodstream and stored in the muscles to supply energy for muscle contraction during activity. A) B) (H2N) CH3 ( O \ l // C - N - CH2 - C //
  64. Math

    The temperature of a chemical compound was 1°C at 3​:00 A.M. During a​ reaction, it dropped 3°C per minute until 3​:13 A.M. What was the temperature at 3:13 ​A.M.?
  65. Chemistry

    A student collected concentration data to determine the rate of the decomposition of N2O5 to NO2 and O2. The data were recorded in the table below. What is the rate law of this reaction? k[N2O5] k[N2O5]2 k k[NO2]
  66. grammar

    1.Christina and Christopher worked together and completed a project about astronomy. simple subject and compound predicate? 2.Jennifer and her brother were not allowed to go to Great Adventure with the Jones family. Compound subject and compound predicate
  67. Science

    Can an element be separated from a compound? Can an element form a compound? The reaction of zinc metal and hydrochloric acid creates hydrogen gas, an element. if we create this element in a tube what property of this element requires us to keep the tube
  68. Chemistry

    How many half-lives have passed if 87.5% of a substance has decomposed? How many if 99.999% has decomposed? For 87.5% decomposition 1/8 is left. (1/8) = (1/2)^3 Three half lives is the answer Fot 99.999% decomposition, 10^-5 is left. Solve 10^-5 = (1/2)^n
  69. Science

    i need a bit of help finding out how to do this problem. just tell me how and ill take it from there. Q.A compound containing carbon, hydrogen, and Oxygen is found to be 40% carbon and 6.7% hydrogen by mass. the molar mass of this compound is between 115 g
  70. Chem

    i need a bit of help finding out how to do this problem. just tell me how and ill take it from there. Q.A compound containing carbon, hydrogen, and Oxygen is found to be 40% carbon and 6.7% hydrogen by mass. the molar mass of this compound is between 115 g
  71. Chemistry

    The solubityof a compound in water is 6.8g/100ml at 0degreesC and 0.33g/100ml at 25degreesC.calculate the amount of water required to crystallize 10g of the compound.If the compound is collected at 25degreesC what is the maximum possible yield present?
  72. Science - chemistry

    Write the complete ionic equation for the reaction of magnesium phosphate with lead (II) nitrate. Include which ions will be aqueous and which compound will precipitate. (Valences: Mg=+2, PO4=-3, Pb=+2, NO3=-1)
  73. Chemistry

    One of the flavouring compounds that have been isolated from aniseed oil is anethole. a.What is the configuration of the molecule, cis or trans? b. The compound will react with bromine. i.What would you observe? ii.Write an equation for the reaction.
  74. CHEMISTRY

    4BF3+3H2O=H3BO3+3HBF4 if the reaction vessel contains 0.496 mol BF3 and 5.63g of H2O, which compound is the limiting reactant? how many molesof HBF4 can be produced?
  75. Chemistry

    I need help with this lab. Write the equation for the decomposition of the hydrate, CuSO4*XH2O. Mass of crucible and hydrate: 93.000g Mass of crucible and pure salt: 91.196g I need to calculate the following: 1. mass of water in hydrate sample(g) 2. number
  76. Chemistry re-post URGENT

    Chemical analysis reveals capsaicin to contain 71.0% of carbon, 8.60% hydrogen, 15.8% oxygen and 4.60% nitrogen. a) Determine the empirical formula of capsaicin b) Each molecule contains one atom of nitrogen. What is the molecular formula of capsaicin? I
  77. Chemistry

    Chemical analysis reveals capsaicin to contain 71.0% of carbon, 8.60% hydrogen, 15.8% oxygen and 4.60% nitrogen. a) Determine the empirical formula of capsaicin b) Each molecule contains one atom of nitrogen. What is the molecular formula of capsaicin? I
  78. Chemistry

    Time, (min): 0 10 20 30 Moles,(trans): 1.00 0.90 0.81 0.73 Given the following data, what is the order of the reaction? How long will it take for the half of the trans compound to decompose?
  79. Chemistry

    Question 6: From the following data, calculate ΔH° for the reaction O3(g) +NO(g)----->O2(g)+NO2 (g) Compound ΔH°f (kJ/mol) O3 142.7 NO 90.3 O2 0 NO2 33.2 (If that was jumbled up i Dont understand?
  80. chemistry

    a sample consisting 22.7g of a nongasous unstable compound X is placed inside a metal cylinder with a radius of 8Cm and a piston is carefully placed on the surface of the compound so that for all practical purposes the distance between the bottom of the
  81. Chemisty

    A 5 μL drop of compound X, a 7 μL drop of compound Y, and a 15 μL of compound Z are placed in a closed container with 5 mL water and 2.5 mL air. The system is equilibrated at 25°C. Determine the fraction of the total X, Y, and Z mass associated with
  82. Chemistry

    you were asked to determine the melting point of an unknown compound in order to identify at as one of the compounds you had previously examined. What else could you have done to make sure that your unknown was indeed the compound you believed it to be,
  83. Chemistry

    For the Following sets of compounds determine the best solvent, by looking at structure, also by looking at solubility vs. temp. Which is the best solvent for crystalization, in which the compound is too soluble, and in which solvent the compound is not
  84. Algebra

    The half-life of a specific radioactive compound is 20 years. The equation used to model this half-life is y = 5 1/2(t/20) where t represents time. Currently, there are 5 pounds of this compound 15 feet below the earth's surface. When will there only be 4
  85. chemistry

    2.9 The standard enthalpy of formation of the metallocene bis(benzene)chromium was measured in a calorimeter. It was found for the reaction Cr(C6H6)2(s) → Cr(s) + 2 C6H6(g) that . Find the corresponding reaction enthalpy and estimate the standard
  86. chemistry

    Solid sodium nitrate can be decomposed to solid sodium nitrite and oxygen gas. If the percentage yield for the reaction is 80.4%, calculate the grams of sodium nitrite that will result from the decomposition of 955grams of sodium nitrate. 2 NaNO3 ¨ 2
  87. ChemistryDrBob222

    Arrows disappeared from below added them back to the equations. The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in
  88. Chemistry

    If I have 0.17g of Mg and 0.10g of O, and I am asked to find the empirical formula for magnesium oxide, is the following the right way to go about it? Convert g-> mol 0.17g=0.01mol Mg 0.10g=0.01mol O Divide by smallest mole amt. (0.01mol) 0.01mol/0.01mol=1
  89. Chemistry

    A compound of B and H is found to have a mass percent composition of 81.1% Boron. Its empirical formula is B2H5. A mass spectrometry experiment tells us that the molecular mass is 53.3 g/mol. What is its molecular formula? So I feel like this is a trick
  90. ap chem

    A student collected concentration data to determine the rate of the decomposition of N2O5 to NO2 and O2. The data were recorded in the table below. What is the rate law of this reaction? A. k[NO2] B. k[N2O5] C. k D. k[N2O5]2 [N2O5]M- .5,.44,.39,.34,.30,.27
  91. Chemistry(Please check)

    The decomposition of an aldehyde solution in carbon tetrachloride is a first order reaction with a rate constant of 1.20 x 10-3 min-l. If we start with [aldehyde] = 0.0500 molar, what will the concentration be 150 minutes later? 1.20e-3(150) = 0.18
  92. chemistry

    why is the molecular formula of oide of arsenic in its gaseous state is not neccessarialy the same as its empirical formula what does this mean and how do i do it Molecules are known to dimerize or trimerize. We actually don't know what the molecular
  93. Chemistry

    Enter the formulae of the products and give their states. Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none". ZnCO3(s) + heat ---> I know it's a decomposition reaction, so I
  94. Quick English check

    Identify the choice that most closely matches the italicizes word or phrase below. The words are: analytical, comprised, deemed, empirical, extrapolate, inference, mitigate, paradigm, speculate, stratagem. 1. The prevailing framework of what it means to
  95. Chemistry

    a compound is made up of iron and oxygen, only. the ratio of iron ions to oxide ions is 2:3 in this compound. the iupac name for this compound is?
  96. Chemistry

    Prior to their phaseout in the 1980s, chemicals containing lead were commonly added to gasoline as anti-knocking agents. A 3.279 g sample of one such additive containing only lead, carbon, and hydrogen was burned in an oxygen rich environment. The products
  97. Chemistry

    Prior to their phaseout in the 1980s, chemicals containing lead were commonly added to gasoline as anti-knocking agents. A 3.279 g sample of one such additive containing only lead, carbon, and hydrogen was burned in an oxygen rich environment. The products
  98. Chemistry

    Prior to their phaseout in the 1980s, chemicals containing lead were commonly added to gasoline as anti-knocking agents. A 3.279 g sample of one such additive containing only lead, carbon, and hydrogen was burned in an oxygen rich environment. The products
  99. Chemistry

    8) ( 1 point) What is the maximum number of grams PH₃ that can be formed when 3.4 g of phosphorus reacts with 4 grams of hydrogen to form PH₃? P₄ (g) +6H₂ (g) → 4PH₃ (g) * 3.7 g 6.8 g 45 g 270 g 10. Lead nitrate can be decomposed by heating.
  100. physical science

    give one word/term for each of the following descriptions. 1.A substance that donates electrons in chemical reaction. 2.The formula showing the simplest whole number ratio in which the atoms combine to form a compound.