1. chemistry help

    An amount of 414.27 g of zinc sulfide (ZnS, MM=97.44 g/mol) reacts with 99.58 g of oxygen gas (O2, MM=31.999 g/mol) at a constant temperature of 298.0 K and constant pressure of 1.00 atm. The reaction: 2 ZnS(s) + 3 O2(g) --> 2 ZnO(s) + 2 SO2(g) dH =
  2. chemistry help

    An amount of 414.27 g of zinc sulfide (ZnS, MM=97.44 g/mol) reacts with 99.58 g of oxygen gas (O2, MM=31.999 g/mol) at a constant temperature of 298.0 K and constant pressure of 1.00 atm. The reaction: 2 ZnS(s) + 3 O2(g) --> 2 ZnO(s) + 2 SO2(g) dH =
  3. chemistry

    what is the Molarity (M) of a 0.87m aqueous solution of ammonia, NH3? The density of the solution is 0.823 g/mL. Answer: 0.71 M So I have: 0.823 g H2O+NH3/1 ml H2O+NH3 17.034 g NH3/1 mol 18.016 g H2O/1 mol 0.87 mol NH3/1 kg H2O I've tried this several ways
  4. biology A

    Complete the analogy below by selecting the correct answer. electron transport chain : _____ production :: Calvin cycle : _____ production A>> ATP; glucose B>> Water; glucose C>> ATP; oxygen D>> Glucose; ATP I'm pretty set on A,
  5. chemistry

    I need a formula for: 0.5 grams of sodium chloride is dissolved to make 0.05 liters of solution. next 0.5 grams of sodium chloride is dissolved to make 0.05 ml of solution. next 670 grams of Pb (C2H3O2)4 are dissolved to make 3.5 ml of solution.
  6. science

    'Imagine there is a tank of unknown gas that contains 53.31% carbon, 11.18% hydrogen, and 35.51% oxygen by mass. At 35.0 °C and 0.455 bar, 2.00 L of the gas has a mass of 3.20 g. Using this information, answer the following questions. a.) What is the
  7. Biology/Chem

    Soy sauce is prepared by fermenting a salted mixture of soybeans and wheat with several microorganisms including yeast over a period of 8-10 months. After the solids are removed, the resulting sauce is rich in lactic acid and ethanol. How aere these 2
  8. CHEMISTRY

    Use the following balanced chemical equation to calculate the mass of carbon dioxide produced from the burning of 5.50 kg of jet fuel which can be represented by the molecule C12H26. You should quote your answer to 3 significant figures in units of kg. The
  9. Biology - Help!!

    Can someone check these for me? 1. Excretion is the process of (1 point) exchanging carbon dioxide for oxygen. removing metabolic wastes from the body.*** pumping blood throughout the body to supply nutrients and oxygen to cells. breaking food down into
  10. Chemistry

    Combustion of a 0.1595 g of menthol (156 g/mol) produces .449 g of Carbon Dioxide and 0.184 g of Water. What is the formula of menthol? I am really confused as to where to start. I converted the Carbon Dioxide and Water to moles and got .102 mol for both
  11. combustion

    A glass melting furnace is burning ethene in pure oxygen (not air). The furnace operates at an equivalence ratio of 0.9 and consumes 30 kmol/hr of ethene. Determine the energy input rate based on the LHV of the fuel in terms of kW. •Determine O2
  12. chemistry

    From the following combustion: 1-butanol + oxygen = carbon dioxide + water. How many grams of carbon dioxide and water are produced when 130.6 grams of 1-butanol is completely burned? Please help me! I have not a clue! Thanks so much!
  13. Chemistry

    Magnesium forms both an oxide and a nitride when burned in air. Discuss the formation of magnesium oxide and magnesium nitride when magnesium atoms react with oxygen and nitrogen atoms.
  14. Chemistry

    Last week we drew Lewis dot structures of azide (N31-), a crucial component in automobile collision safety airbags. During an impact, a sensor ignites a detonator cap that sets off the following rapid reaction: 2NaN3(s) → 2Na(s) + 3N2(g) Part A What
  15. Finance

    RCA made a coupon payment yesterday on its 6.25% bonds that mature in 11.5 years. If the required return on these bonds is 9.2% nominal annual, what should be the market price of these bonds?
  16. chemistry

    When hydrochloric acid reacts with magnesium metal, hydrogen gas and aqueous magnesium chloride are produced. What volume of 4.8 M is required to react completely with 2.60 g of magnesium?
  17. FIN

    Phoenix, Inc made a coupon payment yesterday on its 6.25% bonds that mature in 11.5 years. If the required return on these bonds is 9.2% nominal annual, what should be the market price of these bonds?
  18. CHEMISTRY

    Zinc metal reacts with hydrochloric acid to produce zinc (II) chloride and hydrogen gas. what volume (in mL) of 2.0M HCl is required to dissolve a 10.0g piece of zinc?
  19. chem

    Mercury(II) Oxide decomposes upon heating, producing elemental mercury. This reaction has an enthalpy value of 90.8 kJ/mol. How much heat is required to produce 2000 lbs of mercury?
  20. physics

    A worker on scaffolding 75 ft above the ground needs to lift a 410 lb bucket of cement from the ground to a point 25 feet above the ground by pulling on a rope weighing 5 lb/ft. How much work is required
  21. Math

    a man plans to build a teepee in the back yard for his children. The distance between the stays is 12 ft. the height to the top of the teepee is 8 ft. what is the length of pipes required for the teepee?
  22. chemistry

    the concentration of a chemical degrades in water according to order kinetics. the degradation constant is 0.2 day^-1. if the initial concentration is 100.0 mg/L, how may days are required for the concentration to reach 0.14 mg/L?
  23. Calc II

    A worker on scaffolding 65 ft above the ground needs to lift a 390 lb bucket of cement from the ground to a point 20 feet above the ground by pulling on a rope weighing 5 lb/ft. How much work is required?
  24. physics

    given that the mass of an electron is 9.1 x 10^-28 grams and the charge on an electron is 1.6 x 10^-19 Coulombs, calculate the voltage required to lift an electron 5 cm. the question was previously answered, but I did'nt understand it .. could some show me
  25. CHEMISTRY

    Zinc metal reacts with hydrochloric acid to produce zinc (II) chloride and hydrogen gas. what volume (in mL) of 2.0M HCl is required to dissolve a 10.0g piece of zinc?
  26. CHEM

    Butane, C4H10, is a component of natural gas that is used as fuel for cigarette lighters. The balanced equation of the complete combustion of butane is: 2C4H10(g) + 13O2(g)->8CO2(g) + 10H2O(l) At 1.00atm and 23*C , how many liters of carbon dioxide are
  27. chemistry

    An orgnaic compound contains C, H, No, and O. Combustion of 0.1023 g of the compound in excess oxygen yielded 0.2766 g of CO2 and 0.991g of H2O. A asample of 0.4831 g of the compound was analyzed for nitrogen by the Dumas method. At STP, 27.6 mL of dry
  28. Science....HURRY! Please respond ASAP!!!!

    0=X=0 The model above shows how an unidentified element, X, forms covalent bonds with oxygen. In which group on the periodic table does Element X most likely belong? A. Group 6 B. Group 12 C. Group 14 D. Group 18 I think it is either C or D. So X must be a
  29. Help please? Chemistry

    At a certain temperature and pressure, 0.20 mol of carbon dioxide has a volume of 3.1 L. A 3.1-L sample of hydrogen at the same temperature and pressure ____. I think it's supposed to be "contains the same number of molecules" but I'm not sure. And there's
  30. Chemistry

    The homework question said "which 2nd row element has 6 valence electrons and a valence of 2?" I don't really understand the question, because oxygen would be the element with the 6 valence electrons, but wouldn't that mean that it has a valence of 6? Does
  31. Biology - Heart Rate/Blood Pressure

    Hi, can someone help me with these questions? Why is it that athletes have to exercise harder/longer to get max heart rate than people that aren't physically fit? Why does smoking cause rise in blood pressure? (Does it have to do with less oxygen getting
  32. chemistry

    2. Sulfuric acid comes from the oxidation of sulfur. The stages of the reactions are given below: S + O2 --> SO2 ∆H= -296.8 kj SO2 + 1/2 O2 --> SO3 ∆H= -98.9 kj SO3 + H2O --> H2SO4 ∆H= -130.0 kj The typical plant produces 750
  33. Chemistry! urgent

    what volume of gas at 40°C and 1.50 atm is necessary to react with 300 L of hydrogen gas measured at the same conditions? 2H2 (g) + O2 (g) --> 2H20 (g) 1.50 atm= 151.KPa How would I solve this? Because I can't use: PV = nRT I have pressure,
  34. science need help

    2 H2 + O2 = 2H2O 2 grams + 32 grams=_ _ _ _ _grams how would the mass of water formed in the reaction compare to the mass of oxygen and hydrogeb that reacts. in your response be sure to: include they type of change illustrated in the balanced eqaution
  35. chemistry

    In 1774 Joseph Priestly conducted one of his most famous experiments which lead to a method for the preparation of oxygen. The experiment involved heating a sample of mercury II oxide with a large lens. The equation for this reaction is shown below:
  36. Biology

    Stroke volume is the blood pumped by the left ventricle each time it contracts. During a training run the stroke volume of a person is 0.1 dm^3 (100 cm^3). Calculate the pulse rate at an oxygen uptake of 2 dm^3/min. Is there enough information (there is a
  37. Chemistry

    1. Suppose o2, n2 and Ar were placed at 1.00 atm and 273 K in closed containers. A tiny hole is opened in each container, allowing each gas to diffuse into another container filled with neon gas. What is the ratio of the rate of diffusion of nitrogen to
  38. physics

    can anyone plz explain to me what is the electrical nature of water molecules????i look through many information on the websites...i just don't get what they are talking about...PLZ HELP!!THX A LOT!!! The water molecule is the shape of a V. The the oxygen
  39. chemistry

    1-butanol (shown below) burns in the presence of oxygen to give off carbon dioxide and water by the following reaction: C4H9OH + 6 O2 ==> 4 CO2 + 5 H2O If 40.88 mL of 1-butanol burns completely, how many grams of 1-butanol have burned? grams =33.1 bu
  40. Biomechanics

    An 88.9 kg weight lifter is required to perform a snatch movement for their final lift in a weight lifting competition. The standard weight lifting bar is 20 kg and the load attached to the bar was in the form of 6 x 20 kg weight discs, 2 x 10 kg weight
  41. Eric

    Are these correct? 1. Which of the following is a correct statement about homeostasis? a. The effector sends the stimulus to the control center b. The receptor is enhanced by the control center c. The response causes disease d. The receptor sends the
  42. Management accounting

    suppose one chairlift costs $2 million and the slopes and the lift had to be install for $1.3 million, and the lift let 300 skiers on the slopes, for 40 days out of a year) Running the lift cost $500 a day for 200 days for the ski resort openings, now
  43. Science

    Which of the following is NOT true of bacteria? a. Bacteria change the sugar in milk to lactic acid. b. Bacteria change nitrogen into a form plants can use. c. Bacteria change harmful chemicals into harmless ones. d. Bacteria change oxygen into nitrogen.
  44. Chemistry

    Sorry for postiong twice. But I really need to know if the answers I am getting are correct; Nitrogen and oxygen react to produce nitric oxide according to the following equation: N2 (g) + O2 (g) → 2 NO (g) The equilibrium constant for this reaction is
  45. chemistry HELP!!

    Reaction Rate = -(1/2) [d(H2O2)/dt] = [d(O2)/ dt] Using 25 mL of a 0.2 M hydrogen peroxide solution, the following results are obtained from the equation above: 8.62 mL of gas is collected in 120 seconds. (Assume 760 Torr = 1 atm) Room temperature is 25
  46. Chemistry

    Nitric acid, HNO3, is produced from ammonia and oxygen by the consecutive reactions: 4NH3 + 5O2 => 4NO3 + 6H2O 2NO + O2 => 2NO2 3NO2 + H2O => 2HNO3 + NO How many grams of nitric acid can be obtained from 1.00kg NH3 if NO in the third reaction is
  47. chem-speed at STP

    Hi- we were given this question and I have no clue how to figure it out...please help! Which gas molecules have the greatest average speed at STP? [a] SO2( sulfur dioxide) [b] NH3( ammonia) [c] O2( oxygen) [d] N20 (Dinitrogen oxide) Ok, at stp, that means
  48. Chemistry

    When 16 grams of methane gas combine with 64 grams of oxygen, 44 grams of carbon dioxide form, plus water. What mass of water is produced? You can work this problem as a stoichiometry problem OR you can recognize that the law of conservation of mass tells
  49. Anatomy

    explain the effects of smoking on oxygen-hemoglobin saturation. Include in your answer a definition of saturation, the mechanism by which smoking effects saturation, and the consequences to the body Please try researching you question here:
  50. Physics. PLEASE HELP!!

    A skier of mass 71 kg is pulled up a slope by a motor-driven cable. The acceleration of gravity is 9.8 m/s2. How much work is required to pull him 64.6 m up a 33.8 slope (assumed to be frictionless) at a constant speed of 2.53 m/s? Answer in units of kJ
  51. business math

    I'm trying to solve this problem: What sinking fund payment would be required at the end of each three-month period, at 8% interest compounded quarterly, in order to amount to 20,000. I just need to know how to work the problem correctly.
  52. statistics

    11. Suppose we are estimating m. What happens to the required sample size as the population standard deviation increases while the confidence level and desired margin of error remain constant? A) It increases. B) It decreases. C) It does not change.
  53. Physics

    A 5.o kg box is lifted to a height of 10 meters at a constant speed. a)How much power is required to complete this task in 10 seconds? b)Calculate the velocity of the box just as it hits the ground? i have the answers but i need a second opinion a)50 watts
  54. physics

    Consider the system shown in the figure with = 9.5 and = 15.0 . The angles = 59 and = 32. 1)In the absence of friction, what force would be required to pull the masses at a constant velocity up the fixed inclines? the force is now removed. What is the
  55. account

    Required: JZ is a musician who is considering whether to independently produce and sell a CD. JZ estimates fixed costs of $10,000 and variable costs of $4.00 per unit. The expected selling price is $12 per CD. What is JZ's break-even point in units and
  56. Physics

    Ok guys, state the surface powers required to produce the following lenses with +5.75D front curves. a) -0.50DS b) +0.50DS c) +1.75DS d) -1.25DS i'm not sure if it's as straight forward as calculating the difference, eg. a) +5.75 - -0.50 = +6.25. Any help
  57. mathematics

    what does 'dx' signify in the integral and differentiation notation? I was reading integration by substitution method where it is required to replace 'dx' and change the independent variable such that the integral could be transformed.I have read in
  58. Physics

    A 5.o kg box is lifted to a height of 10 meters at a constant speed. a)How much power is required to complete this task in 10 seconds? b)Calculate the velocity of the box just as it hits the ground? i have the answers but i need a second opinion a)50 watts
  59. physics

    A 130 N block rests on a table. The suspended mass has a weight of 63 N. 130 N 63 N µs a) What is the magnitude of the minimum force of static friction required to hold both blocks at rest? Answer in units of N
  60. physics

    The flywheel of an engine has a moment of inertia of 24 kg*m^2. a) if the radius of the wheel is 0.6m, what force is required to accelerate the wheel from rest to an angular velocity of 300 rpm in 6 seconds? b) how many turns does it make during this time?
  61. physics

    A 68.0 kg crate rests on a level floor at a shipping dock. The coefficients of static and kinetic friction are 0.700 and 0.450, respectively. (a) What horizontal pushing force is required to just start the crate moving?
  62. English

    Words left beacon celestial detract precaution retaliate sham uncouth wistful 17.Before we use the blowtorch in our industrial arts class we are required to take the ___ of wearing goggles precaution
  63. Physics

    A hydraulic jack is designed so that when the handle is pushed down 1 m, the piston raising the load moves up 0.015 m. IMA= 66.67 AMA= 26.67 Efficiency= 40% At this efficiency, what is the force required to lift a 5000 N weight?
  64. algebra 2 review

    A training ring for horses is an oval formed from a rectangle with two semicircles on either end. Rounded to the nearest foot, how many feet of fencing is required to surround the entire ring with a fence?
  65. physics

    A hydraulic jack is designed so that when the handle is pushed down 1 m, the piston raising the load moves up 0.015 m. IMA= 66.67 AMA= 26.67 Efficiency= 40% At this efficiency, what is the force required to lift a 5000 N weight?
  66. math 106

    what amortization payment would be required every month, at 12% interest, to pay off a $125,000 mortgage in 10 years? round your answer to the nearest cent. can you work the steps to this problem for me so i can see the problem clearly?
  67. College Algebra

    Hello Steve, it didn't work for "t" i can't get the actual value... Find the time required for an investment of 1 dollars to grow to 7200 dollars at an interest rate of 7.5 percent per year, compounded quarterly
  68. HISTORY

    WHICH WOULD BE THE BEST CHOICE The U.S. Congress is 1 the only democratically elected legislature in the world. 2 prohibited from passing laws that might conflict with state laws. 3 required to reapportion every year. 4 nonpartisan. 5 bicameral. i CAN NOT
  69. Chem

    The information below shows properties of aluminum (Al). DELTAHfus = 10.07 kJ/mol DELTAHvap = 225 kJ/mol Which quantity of heat is required to melt a 342.9-g sample of Al? 127.98 kJ 214.93 kJ 2,851.95 kJ 3,453.00 kJ
  70. criminal justice

    The presentence investigation report (PSI) a. reflects positive school interest in the offender B. is based on the concept of parens patriae C. is required in all jurisdictions D. reflects a classical approach E. none of the above
  71. chemistry

    The solid oxide of generic metal M is added to 75 mL of water and reacts to produce a basic solution that is 0.20 M in the resulting compound. Neutralization of the solution required titration with 27 mL of 0.56 M HCl. How many valence electrons must M
  72. chemistry

    Chromium metal can be plated onto an object from an acidic solution of dichrmonate tions. What average current is required to plate 17.8 g of chronium metal in a time of 2.20 h? ( you will need to construct your own equation for the half-reaction)
  73. Income tax

    Catherine purchased furniture and fixtures (7-year property) for her shop for $80,000 in May 2013. What AMT depreciation adjustment is required in 2013? A. $0 B. $2,864 C. $8,568 D. $11,432 The answer is A?
  74. physics

    The flywheel of an engine has a moment of inertia of 24 kg*m^2. a) if the radius of the wheel is 0.6m, what force is required to accelerate the wheel from rest to an angular velocity of 300 rpm in 6 seconds? b) how many turns does it make during this time?
  75. physics

    A wire of length 60cm and mass 10kg is suspended by a pair of flexible leads in a magnetic field magnitude and direction of the current required to remove the tension in the supporting leads.
  76. Math

    In evening my test plz help me to solve it A room length 3m,20m wide and 6m height. Find the floor is to be tiled.if each tile measures 60cm*50cm,find the no. Of tiles required.
  77. physics

    particle P and Q are undeergoing uniform horizotal circular motion along concentric circle of different radii in clockwise sense . pcomplete each round in 2 min while q does in 5 min. time required by q to make one revolution around P
  78. Psychology

    Bryan was edgy and seemed to lose his temper at the drop of a hat. His sister suggested that he would benefit by practicing an altered state of consciousness. He was surprised to hear his sister suggest that he should take drugs, but was soon corrected
  79. psychology

    Bryan was edgy and seemed to lose his temper at the drop of a hat. His sister suggested that he would benefit by practicing an altered state of consciousness. He was surprised to hear his sister suggest that he should take drugs, but was soon corrected
  80. Business Law

    Background: ABC is a multinational enterprise (MNE) incorporated in State X. ABC entered into a joint venture agreement with XYZ, an MNE incorporated in State Y, to jointly produce a new line of hydraulic equipment in ABC's new factory in State Z, a
  81. Chemistry

    If the radiation of an automobile contains 12L of water, how much would the freezing point be lowered by addition of 5 kg of prestone (glycol, C2H4(OH2))? How many kg of zerone (methyl alcohol, CH3OH) would be required to produce the same result? assume
  82. Chem 100L

    Calculate the molarity of an aqueous NaOH solution if 32.00ml of it is required to titrate .6789g of oxalic acid to a phenophthalein end-point. the balanced chemical equation is H2C2O4 + 2NaOH ---> Na2C2O4 + 2H2O
  83. physics

    A load of 66 N attached to a spring hanging vertically stretches the spring 8.3 cm. The spring is now placed horizontally on a table and stretched 11 cm. What force is required to stretch it by this amount? Answer in units of N.
  84. AP Chemistry

    When hydrochloric acid reacts with magnesium metal, hydrogen gas and aqueous magnesium chloride are produced. What volume of 5.0 M HCI is required to react completely with 3.00 g of magnesium?
  85. Chemistry

    Is this answer correct? Calculate the molar concentration of sodium hydroxide solution if 36.00mL of this solution were required to neutralize 25.00 mL of a 0.2000 M solution of hydrochloric acid. .0288M??????
  86. physics

    The force required to flex a nasal strip and apply it to the nose is 0.25 ; the energy stored in the strip when flexed is 0.0025 . Assume the strip to be an ideal spring for the following questions.
  87. phyics/moon

    The acceleration due to gravity on the Moon's surface is one-sixth that on Earth. What net force would be required to accelerate a 20-kg object at 6.5 m/s2 horizontally on the moon? A) 1.3 N B) 20 N C) 33 N D) 120 N E) 130 N
  88. gRammar

    Proofreading. Proofread the following sentences. Insert punctuation as required. The x-rays revealed: an articular fracture of the tibia, a butterfly fracture of the fibula, and a longitudinal fracture of the femur.
  89. Chemistry

    When hydrochloric acid reacts with magnesium metal, hydrogen gas and aqueous magnesium chloride are produced. What volume of 9.0 M HCl is required to react completely with 5.00 g of magnesium?
  90. Plant Physiology

    I'm confused about the oxygen evolving complex step in photosynthesis..From what I can understand so far, a P680 pigment molecule gets excited in PSII forming P680* which then loses an electron to form P680+ which is a strong oxidant. This then splits 2
  91. chemistry

    Consider the following chemical equilibrium: SO3(g) --> SO2(g) + 1/2 O2(g) and Delta H = 98.9J a. Predict weather the forward or reverse reaction will occur when the equilibrium is disturbed by: i. adding oxygen gas ii. compressing the system at
  92. Please help!

    The following data describe the binding of oxygen to human myoglobin at 37oC. P02 (mm Hg) = 0.5 1 2 3 4 Theta = .161 .277 .434 .535 .605 P02 (mm Hg) = 6 8 12 20 Theta = .697 .754 .821 .885 From these data, estimate: a). P50 b) the fraction saturation of
  93. Living environment(check please)

    When the food relationship in a habitat are illustrated by means of diagram, the result is always a complicated web like pattern. This is due to the fact that 1 many consumers are adapted to use more than one food source 2 producer organisms always
  94. Chemistry

    Please help, I am having trouble solving these problems at nonstandard temperatures. Methanol burns in oxygen to form carbon dioxide and water. Using the balanced reaction, 2CH3OH(l) + 3OH2(g) --> 2CO2(g) + 4H2O(g) 1) Calculate delta H(rxn) in kJ at 24
  95. chem hwk

    a simple hwk question.. i don't understand what i need to do.. 1-butanol (shown below) burns in the presence of oxygen to give off carbon dioxide and water by the following reaction: C4H9OH + 6 O2 ==> 4 CO2 + 5 H2O If 40.88 mL of 1-butanol burns
  96. Science-Urgent

    I did an experiment on a burning candle, and I need help with some of the questions. Thank you very much in return. Please no websites.--more information would be appreciated, thanks:-) I'll list everything of what we went through. Materials: -1 standard
  97. Chemistry

    I'm trying to find if potassium nitrate is polar or non-polar by using the electronegativity scale. Can someone check my work? Electronegativity: potassium: 0.82 nitrogen: 3.04 oxygen: 3.44 =3.44-3.04 =0.82-0.4 =0.4 =0.42 So the final answer is 0.42 and by
  98. science

    what will be the law of conversion of a) 65 grams 70 grams b) magnesium + oxygen = magnesium oxide 45 grams ? grams 80 grams c) sodium hydroxide + hydrochoride acid 40 grams 36.5 grams sodium chloride + water ? grams 18 grams
  99. chem

    Methane is oxidized to water and carbon dioxide in a process, in which 10 % of the methane is converted to CO and 20 % is converted to formaldehyde. What is the yield of the process? How much methane do you need to produce a kg of formaldehyde? How much
  100. science need help

    2 H2 + O2 -> 2 H2O 2 grams + 32 grams -> _ _ _ _ _ grams how would the mass of water formed in the reaction compare to the mass of oxygen and hydrogen that reacts? include types of change illustrated in the balanced equation. explain the conversation