1. chemistry

    A sample of ammonium phosphate(NH4)3PO4 contains 3.18 moles of hydrogen atoms. The number of moles of oxygen atoms in the sample is (1)0.265 (2)0.795 (3)1.06 (4)4.00
  2. Chemistry

    In a certain reaction 0.20g of hydrogen gas combines with 3.20g of oxygen gas.if the relative molecular mass of the compound is 34.0 find its molecular formula (H=1,O=16).
  3. Physics

    An astronaut of mass 70 kg carries an empty oxygen tank of mass 14 kg. He throws the tank away from himself with a speed of 3 m/s. With what velocity does the astronaut start to move through space?
  4. Chemistry

    Heat is given off when hydrogen burns in air according to the equation: 2H2 + O2 ---> 2H2) What is responsible for the heat? I know the answer is froming hydrogen-oxygen bonds gives off energy, but why?
  5. Chemistry

    In the experiment 0.500 g of copper reacted with oxygen to give 0.563 g of copper oxide. What is the empirical formula of the oxide expressed as a chemical formula?
  6. Chemistry

    The gas sulfur dioxide, SO2, oxidizes to form another gas, sulfur trioxide, SO3. How many oxygen atoms are present in 3.20 g of sulfir trioxide?
  7. chemistry

    A 4.78-g sample of aluminum completely reacts with oxygen to form 6.67 g of aluminum oxide Use this data to calculate the mass percent composition of aluminum in aluminum oxide. (Sorry need help with this!)
  8. chemistry

    a 5 g mixture of natural gas containing ch4 and c2h4 was burnt in excess of oxygen yielding 14.5 g of co2 and h2o.What is the weight of ch4 and co2 in the mixture
  9. Chemistry

    In the explosion of a hydrogen-filled balloon, 0.75 g of hydrogen reacted with 6.9 g of oxygen to form how many grams of water vapor? (Water vapor is the only product.) I am really confused on how to do this.
  10. chemistry

    9 grams of carbon and 1.5 grams of hydrogen combined with oxygen to make a compond whose mass is 22.5 and whose relative molecular mass is 60.determine the molecular formula
  11. CHEM HELP PLZZZZZZZZZZZZZZZZZ

    use the experimental molar mass to determine the molecular formula for ocompounds having the following analysis.b) 54.53% carbon 9.15% hydrogen, and 36.32% oxygen; experimental molar mass 88
  12. AP Chemistry

    Given: 2N2(g) +O(2) --> 2N2O(g) Kc =1.2x10^(-35) N2O4(g) --> 2NO2(g) Kc = 4.6x10^(-3) 1/2N2(g) + O2(g) --> NO2(g) Kc= 4.1x10^(-9) Calculate Kc for the reaction between one mole of dinitrogen oxide gas and oxygen gas to give nitrogen tetroxide gas.
  13. Chem repost

    or the compound: carbon in the middle with 3 bonds -double bond to oxygen -bond to Mn(CO)5 -bond to CH3 group is the oxidation state of the metal +1? d count 6? total electron count 20? coordination number 7?
  14. Chemistry

    Um how do i balance these word equations for chemistry... I think I'm suppose to look them up on a common table of ions and then I don't know wat to do ferric Oxid --> iron oxygen what exactly am i suppose to do please tel me thr throught process that's
  15. Chemistry

    Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1
  16. chem post

    or the compound: carbon in the middle with 3 bonds -double bond to oxygen -bond to Mn(CO)5 -bond to CH3 group is the oxidation state of the metal +1? d count 6? total electron count 20? coordination number 7?
  17. Chemistry

    Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1
  18. Chemistry

    Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1
  19. science

    when can the plant start to make its own food? A plant always makes its own food. Ever since it existed it made its own food through photosynthesis. The leaves take in the sunlight and form it into food. It also releases oxygen.
  20. Chemistry

    A compound is found to contain 50.05 % sulfur and 49.95 % oxygen by mass. What is the simplest (empirical) formula for this compound? They said to assume that it is 100 grams. I found the molar mass. S- 32.06 0-16.00 But now I don't know what to do. Please
  21. College Chemistry 3

    Find the empirical Formula of a compound that is 30.4% nitrogen by mass, and consists of only nitrogen and oxygen. What is its molecular formula if its molar mass is 92g/mol?
  22. Science

    What is the function of a cell wall? 1.to protect and sopport the cell****** 2.To perform different functions I’m each cell 3.To prevent water from passing through the cel 4.to prevent oxygen from entering the cell
  23. Chemistry

    Trimix 10/50 is a gas mixture that contains 10% oxygen and 50% helium, ant the rest is nitrogen. If a tank of Trimix 10/50 has a total pressure of 2.07 x 10 4 kPa, then what is the partial pressure of helium?
  24. Chemistry

    An unknown metal, m, forms an ionic compound with the formula, M2S3. Which formula represents the compound formed by the metal with oxygen? a) MO b) MO2 c) MO3 d) M2O3
  25. Chemistry

    Is the reaction of 8 grams of natural gas and 38 grams of oxygen gas to form 17 grams of carbon dioxide in 19 grams of water consistent with the law of conservation of mass?
  26. Chemistry

    4 L of oxygen at a pressure of 400 Kpa and 1L of nitrogen at 200 Kpa were introduced in to 2 L vessel. (A)What is the total pressure of the gases in the vessel. (B)What is the mole fraction of each gas?
  27. chemistry

    A 2.077g sample of an element which has an atomic mass between 40 and 55 reacts with oxygen to form 3.708g of an oxide. Determine the formula mass of oxide ( and identify the element)
  28. Chemistry

    Calculate the ratio of the effusion rate of oxygen gas (O2) to that of nitrogen gas (N2). Express your answer in decimal form and calculate your answer to at least four sig figs.
  29. chemistry

    How many grams of carbon dioxide can form when a mixture of 3.60 g ethylene (C2H4) and 2.70 g of oxygen is ignited, assuming complete combustion to form carbon dioxide and water?
  30. Science 8th grade

    Please check my answer thanks Which of the folowing process is achieved through osmosis ? A. A cube of sugar didilving in coffee B. Particles of oxygen filling the lungs C. Water moving across thr cell membranne D. Transport of proteins from the
  31. chemistry

    A sample of sulfer, mass 2.56 g is burned in excess oxygen inside a calorimeter of heat capacity 923JK and insulated by 815g of water. If the sole product of combustion is SO2, what is the expected increase in temperature? I don't need the answer, just the
  32. Chemisty - Unsure how to proceed- Combustion rxn

    Question as follows: If you combusted 23g of ethanol with an excess of oxygen how much heat would be released or absorbed? the only thing I've deduced is the chemical reaction: C2H6O + 302 -> 3H20 + 2C02 I'm not sure how to proceed. I need Q. Not sure
  33. Chemistry

    1) What volume of oxygen gas at 28 Celsius and 102 kPa is needed to react completely with 150 g of iron according to the following reaction. Fe(s) + O2 (g) FeO(s) 2) A bunsen burner is lit in a lab that at 24.7 Celcius and 1.07 atm. What mass of water is
  34. science

    can u pl answer the following 1. _______ used in air craft to measure altitudes . 2.The metal that burns in oxygen with a dazzling light is _________ . 3. the gas liberated on heating copper corbonate is _________ . 4 .what is king of chemicals ? 5. what
  35. Chemistry

    Hello! I am having a little difficulty answering these two questions on my homework, I was wondering if anyone could please help me out! Thank you! 1) Consider the following balanced chemical equation for the neutralization reaction of calcium hydroxide
  36. AP Chemistry

    When a sample of methyl salicylate weighing 5.287 grams is burned in excess oxygen, 12.24 grams of CO2 and 2.522 grams of H2O are formed. What is the empirical formula for oil of wintergreen? I know the answer is C8H8O3, I just need help finding out how to
  37. Chemistry

    The reaction for the metabolism of sucrose, C12H22O11, is the same as for its combustion in oxygen to yield CO2(g) and H2O(l). The standard heat of formation of sucrose is -2230 kJ mol-1. Based upon data in Table 6.2 and problem 6.75 the amount of energy
  38. Chemistry

    Acetylene(C2H2) torches are used in welding. How much heat (in kJ) evolves when 2.0L of C2H2 (d=1.0967kg/m3) is mixed with a stoichiometric amount of oxygen gas? The combustion reaction is C2H2(g)+52O2(g)→2CO2(g)+H2O(l),
  39. chemistry

    The density of acetone vapor in equilibrium with liquid acetone, (CH3)2CO, at 33.1°C is 0.832 g L?1. What is the vapor pressure of acetone at 33.1°C, expressed in kilopascals? agian i am confused with formulae, hoe you can helpm thanks! change 0.832 g to
  40. language arts

    which of the following statements most accurately describes Mr. Lapham and his daughter-in-law Mrs. Lapham? A. Mr. Lapham is kindly and pious; Mrs. Lapham is pragmatic and determined B. Mr. Lapham is concerned about money; Mrs. Lapham is concerned about
  41. Chem

    A sample of an unknown biochemical compound is found to have a percent composition of 55.03 percent carbon, 5.54 percent hydrogen, 32.10 percent nitrogen and the balance oxygen. What is the simplest formula for this compound ? How do I do this?
  42. Chemistry (mol)

    2CO + O2 → 2CO2 If 3.4 moles of carbon dioxide (CO2) form at the end of the reaction, how many moles of carbon monoxide (CO) and oxygen gas (O2) entered the reaction?
  43. Chemistry

    Analysis of a sample of an organic compound showed it contains 39.9%carbon,6.9%hydrogen and 53.2%oxygen. a)calculate the empirical formula b)if the relative molecular mass is 60,what is the molecular formula of the compound.(C=12,H=1,O=16)
  44. Chemistry

    In the balanced equation for the combustion of 2,2,4-trimethyloctane (C11H24), the coefficient of the organic compound is...the coefficient of oxygen gas is ...the coefficient of carbon dioxide gas is...and the coefficient of liquid water is.
  45. Chemistry

    A sample of oxygen gas at 295 kPa takes up 456 L of space at standard temperature (the “T” in STP). What is the new volume when the pressure is lowered to standard pressure (the “P” in STP)?
  46. Chemistry

    How do you figure out how mch oxygen gas escaped when Potassium Chlorate is decomposed in a reation? Also what mass of Potassium Chlorate was decomposed in the experiment? I conducted the experiement but don't know how to do this.
  47. Physics

    What is the total pressure, in atmospheres, of a 10.0 L container that contains 10 moles of nitrogen gas and 10 moles of oxygen gas at 300 K? I tried using PV=nRT and added both P together but kept getting the wrong answer. n=10, T=300 K, V=1x10^-3 m^3
  48. AP CHEMISTRY!!!!

    Carbon monoxide reacts with oxygen to form carbon dioxide by the following reaction: 2 CO(g) + O2(g) → 2 CO2(g) ∆H for this reaction is −566 kJ/mol rxn. What is the ∆H for CO(g)?
  49. Chemistry

    In an experiment 10.124 g of magnesium is reacted with 4.273 g of oxygen gas according to the equation: Mg + O2 ==> MgO. A. What is the limiting reactant? B. What mass of the other reactant is in exess? C. What mass of MgO is produced?
  50. Science

    Lack of oxygen in a pond may be a limiting factor. True or False? Please reply ASAP, thanks. Limiting factor for what? For fish and other animal life, this would be true. I hope this helps. Thanks for asking.
  51. Physics

    Please show steps and thank you! An astronaut of mass 70 kg carries an empty oxygen tank of mass 14 kg. He throws the tank away from himself with a speed of 3 m/s. With what velocity does the astronaut start to move through space?
  52. Chemistry

    In the explosion of a hydrogen filled balloon, 0.50 g of hydrogen reacted with 4.0 g of oxygen to form how many grams of water vapor? (water vapor is the only product)
  53. Chemistry

    A mixture of gases at 760.0 torr contains 35.0% nitrogen, 22.0% oxygen , and 43.0% carbon dioxide by volume. What is the pressure of the carbon dioxide gas in torr?
  54. chemistry.

    Methane, CH4 burns in oxygen gas to form carbon dioxide and water. How many moles of carbon dioxide will be formed from 8.0g of methane?
  55. physics

    A rigid tank contains 38:0 kg of O2 gas at a pressure of 9:70 atm. If the oxygen is replaced by helium, how many kilogram of helium will be needed to produce a pressure of 8:00 atm?
  56. Chemistry

    Which will produce a decrease in entropy? dissolving sodium chloride in water dissolving oxygen in water sublimation of naphthalene is it the third option, sublimation?
  57. CHEMISTRY

    which one of the following reactions represents the balanced chemical equation for the formation of water from hydrogen gas and oxygen gas? a. 2H(g) + O(g) a H2O(I) b. H2(g) +o(g) a H2O(I) c. 2 H2(g) + O2(g) a 2 H2O(I) d. 2 H(g) + 1/2 O2(g) a H2O(I)
  58. college

    One mole of oxygen gas is at a pressure of 5.10 atm and a temperature of 32.0°C. (a) If the gas is heated at constant volume until the pressure triples, what is the final temperature?
  59. chemistry

    I have 3 grams of CaCI2 and dissolve this into 0.5 L water. What is the concentration in g/dl (grams/deciliter)? I take 10 milliliters of this solution and add it to 990 milliliters of watet fo a total of 1000 milliliters. What is the concentration of this
  60. Calculus

    Following 2 questions are from a book at a point where L’Hopital’s Rule, Squeeze Theorem etc. have not been discussed and limits (A) and (B) as given below are to be evaluated by simple methods like algebraic simplification etc. 1. Int. of (xlogx)dx
  61. Calculus

    Following 2 questions are from a book at a point where L’Hopital’s Rule, Squeeze Theorem etc. have not been discussed and limits (A) and (B) as given below are to be evaluated by simple methods like algebraic simplification etc. 1. Int. of (xlogx)dx
  62. Chemistry

    If The Rate of Diffusion Of Oxygen Is Taken As The Rate Of 1. What Will Be The Rate Of Diffusion Of Methane Whose Relative Molecular Mass Is 16
  63. chemistry 101

    How many moles of oxygen are in 3.45 mol of diphosphorus pentoxide? options: 5.75 mol O 13.5 mol O 6.90 mol O 3.45 mol O 17.3 mol O
  64. chemistry

    A certain compound contains only vanadium and oxygen. A 35.00 g sample of the compound contains 19.61 g of vanadium. Determine the empirical formula of this compound.
  65. Chemistryq

    A cylinder of gas contains 96.0 g of oxygen gas, O2. If the volume of the cylinder is 9.00 liter and at 25.0 degrees C. What is the pressure of O2 in the cylinder?
  66. chemistry

    in 2CO(grams) + O2(grams) => 2CO2(grams), what is the ratio of moles of oxygen used to moles of CO2?
  67. Chemistry

    Asprin, c9h804, is produced through the following reaction of salicyclic acid, c7h6o3, and acetic anhydride, c4h6o3. chemical equation: c7h6o3 + c4h6o3 yields c9h8o4 + hc2h3o2 (all numbers in this equation are subscripts) At 20 degrees Celsius. how many
  68. Physics

    In cold climates, including the northern United States, a house can be built with very large windows facing south to take advantage of solar heating. Sunlight shining in during the daytime is absorbed by the floor, interior walls, and objects in the room,
  69. chem

    hemoglobin, the oxygen-carrying protein in red blood cells, has four iron atoms per molecule and contains .340 percent iron by mass. calculate the molar mass of hemoglobin! thanks! :)
  70. Chemistry

    According to your calculations a reaction should yield 5.67 g of oxygen O2. What do you expect the volume to be at 23 degrees C and 0.985 atm? I got the all the amounts 5.67 g 23 degrees C = 296 K .985 atm And use the ideal gas law Can you help me out by
  71. de Broglie Wavelength

    The presence of oxygen atoms on the surface results in auger electrons with a kinetic energy of approximately 505 eV. What is the de Broglie wavelength of this electron? [KE= (1/2)mv^2; 1 electron volt (eV) = 1.602*10^-19 J]
  72. chemistry pls help me asap

    2.08g of metal Y react with 0.96g of oxygen to form a metal oxide.The empirical formula of the metal oxide is Y2O3.What is the relative atomic mass of metal Y.
  73. science

    The chemical formula for glucose is C6H12O6. Six molecules of carbon dioxide (CO2) react with six molecules of water (H2O) to form six molecules of oxygen (O2). How many molecules of glucose will be produced? A 1 B 6 C 12 D 36 can anyone help me figure
  74. Science 7R - HW Qs. Check (PLZ read!)

    What is the difference between aerobic and anaerobic organisms? My Answer: Aerobic requires oxygen, anaerobic doesn't. Is my answer to this question is correct. Please reply this post! Thank You!
  75. Chemistry

    If 0.200mol of nitrogen gas and 0.200mol of oxygen gas react, what is the limiting reactant? N2(g)+O2(g)→2NO(g) How many moles of NO are produced according to the equation? Please show how to perform this equation with the answer please.
  76. science

    I am currently learning about respiratory system in anatomy and this question is not very clear to me: moves from blood to alveoli: _______ moves from alveoli to blood: ________ I am thinking it may be carbon dioxide and oxygen respectively, but I am not
  77. Chemistry

    14 grams of coal undergoes complete combustion in 58 grams of oxygen gas. What volume of gas (measured at 25 degrees celsius and 100 kPa) is present when the reaction is complete?
  78. biology

    I have a question about reduced and oxidized chemicals and potenital enery. Reduced have weaker PE because they hold on to their electrons and oxidized have strong PE because they can let go electrons right? If I am right then why is that CO2 has a low PE
  79. integrated chemistry and physics

    In a water molecule, two hydrogen atoms bind to one oxygen atom. How many lone pairs of electrons will be shown around each hydrogen atom in the Lewis structure of water?
  80. chemistry

    some oxygen occupies 500.0 ml when its temperature is 40.0 C . if you wished to decrease the volume by 100.0 ml, to what temperture celsius would you need to lower the gas? not sure how to set this up right..keep thinking i need to subtract 100.0 from
  81. Chemistry

    Use oxidation numbers to identify if this reaction is REDOX reactions. SO2(g) + H2O(l) -> H2SO3(aq) for oxidation #s I got: SO2 = -2 for the S = -2 for the o2 H20 = +1 for H2 = -2 for O --> H2SO = +1 for H2 = -2 for S = -2 for O3 There for one oxygen
  82. Chemistry

    What volume of hydrogen is necessary to react with five liters of nitrogen to produce ammonia? (assume constant temprature and pressure) Balanced equation- N2 + 3H2= 2NH3 After finding this answer, what volum of ammonia is produced in this reaction? 1.
  83. Writing

    Throughout this course, you will be asked to reflect on various topics in journal entries. Your Topic 2 entry will be about your program of study. The purpose of writing the journals is to provide you with an informal way of learning to express yourself
  84. Science help,Anyone?

    1. Why is it rare for the soft parts of an organism to become a fossil? The soft parts take a long time to decay. The soft parts can be eaten by other animals. The soft parts cannot be buried in sediment. The soft parts form petrified fossils. 2. Which of
  85. Chemistry

    a 6 g sample of magnesium was burned in a crucible producing 10 g of magnesium oxide. What mass of oxygen reacted with magnesium to form the 10 g of magnesium oxide?
  86. chemistry

    If four grams of Oxygen and four grams of Helium are placed in a five liter vessel at 338 K, what will be the partial pressure of each gas and the total pressure in the vessel?
  87. physics 101

    At what temperature is the root mean square speed of oxygen molecules equal to the root mean square speed of hydrogen at 27 degrees?
  88. chemistry

    Which situation will violate the octet rule? a. 3 bonds to boron b. 3 bonds to and a lone pair on oxygen c. 5 bonds to carbon d. 3 bonds to carbon
  89. Chem

    How many oxygen atoms do you have in 2.00 grams of calcium phosphate? Do you use avogadro's number and how? How many Ca^2+ ions do you have in 2.00 grams of calcium phosphate? Any help would be greatly appreciated.
  90. Chemistry

    Which element is oxidized and which element is reduced in this redox reaction? CO2(g) + H2(g) --> 2CO2(g) + H2O(g) Is Oxygen oxidized and hydrogen reduced?
  91. chemistry

    An analysis of an unknown compound found it contained 40 g potassium, 52 g chromium and 56 g of oxygen. a) What is the empirical formula for this compound? Show the work you did to determine the formula. b) What type of compound is it, ionic, covalent or a
  92. chemistry

    iron+sulphur together are a mixture of small grains yellow and dark grey.Its chemical symbol is 'Fe + S'.When it reacts with oxygen they create a new chemical substance; Iron Sulphide. What do you put for 'explain the reaction using the Big Idea of Energy?
  93. physics student

    A tank holds 2.85 L of oxygen at 22.1 Celsius and 235 atm. (A) how many moles of gas does the tank contain? (B) what is the average kinetic energy per molecule ? the answer in the text book is (a) 27.7 moles (b) 2.381x10^7pa i just want the formula so i
  94. Biology

    To survive as an individual, all animals must maintain homeostasis. Which of the following is NOT a part of homeostasis? A.eliminating wastes from their body B. gathering and responding to information in their environment C. reproduction- to produce viable
  95. Marine Science

    How much of the oxygen we breathe is produced by pytoplankton? 20%, 35%, 50%, 7% I think the answer is 50%. Am I correct. All of the following are adaptations some phytoplankton have for floating except? 1) Cells have large cavity in the center 2) spines
  96. chemistry

    1 gm of magnesium is burnt in a closed container which contains 2 l of air at ntp containing 21 percent oxygen by volume find limiting reagent, mass of excess reagent left over, mass of mgo produced, number of mg and oh ion formed by dissolving it with
  97. "Given Molality, calculate..."

    "Given: An aqueous solution of C6H12O6 with a density of 1.18 g/ml" I) Calculate Molarity 1) It firsts asks me to, "State the moles of solute" 2) Calculate the mass of the solute in grams - I think I can do this if I know how to get #1 3) Later it also
  98. biology

    Bromothymol blue (BTB) is a chemical that turns yellow in the presence of carbon dioxide. In the presence of oxygen, BTB stays blue. In his science class, Sanjay used BTB to test for the presence of those two gases in three situations. *Sanjay's Procedure*
  99. U.S. Government

    I have this question on a homework assignment and I need help. Under Chief Justice Marshall's definition of "interstate commerce" as quoted from the Gibbons v.Ogden case, which one of the following activities would most likely be subject to regulation by
  100. CHEM

    Calculate the density of oxygen, , under each of the following conditions: STP 1.00atm and 25.0 degrees celsius Express your answers numerically in grams per liter. Enter the density at STP first and separate your answers by a comma.