calculate the molar weight of Freon-II, of 8.29 liters of its vapor at 200 degrees celcius and 790 mm Hg has a mass of 30.5 g.?

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  2. Chemistry

    Freon-12 is formed as follows: 3 CCl4 + 2 SbF3 -> 3 CCl2F2 + 2 SbCl3 150 g tetra chloromethane is combined with 100 g antimony (III) fluoride to give Freon-12 (CCl2F2). Identify the limiting and excess reagents, and calculate how many grams of Freon-12 can

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    Gasoline is a mixture of hydrocarbons, a major component of which is octane,CH3CH2CH2CH2CH2CH2CH2CH3. Octane has a vapor pressure of 13.95 torr at 25 degrees celcius and a vapor pressure of 144.78 torr at 75 degrees celcius. Use these data and the equation

  7. chemistry

    calculate the heat energy required to raise the temperature of a 500. gram iron pipe from 25 degress celcius to 100 degrees celcius. the specific heat for iron is .45 J/g degrees celcius

  8. chemistry

    The vapor pressure of dichloromethane, CH_2Cl_2, at 0 degrees celcius is 134 mmHg. The normal boiling point of dichloromethane is 40 degrees celcius. Calculate its molar heat of vaporization (in kJ/mol).

  9. Chem.

    Ethanol has a heat of vaporization of 38.56 KJ/Mol. And a normal boiling point of 78.4 degrees celcius. WHAT is the vapor pressure of ethanol at 18 degrees celcius??

  10. science

    When 90 kJ is removed from a 2-kg copper bar its temperature drops from 200 degrees celcius to 85 degrees celcius what is the specific heat of the iron?

  11. Multon Middle

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  12. Chemistry

    Calculate the molar enthalpy for the following reaction. HCl(aq) + NH3 (aq) --> NH4Cl (aq). HCl = 50 ml (2.00M) NH3 = 50 ml (2.05 M) Delta T = 9.28 degrees Celsius. Ccal = 28.9J/g degrees celcius.

  13. Chemistry

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  14. Chemistry

    Assuming complete dissociation of the solute, how many grams of KNO3 must be added to 275 mL of water to produce a solution that freezes at -14.5 degrees celcius ? The freezing point for pure water is 0.0 degrees celcius and Kf is equal to 1.86 degrees

  15. ap chemistry

    a cubic piece of uranium metal (specific eat capacity= .117 J/g degree celcius) at 200.0 degrees celcius is droped into 1.00 L of deuterium oxide ("heavy water", specific heat capacity=4.211 J/g degree celcius) at 25.5 degrees celcius. the final

  16. Chemistry, HELP!!

    a) If the volume of a flask is 165 mL and the mass of the vapor in the flask is 0.2136 grams, what is the density of vapor in the flask? b)If the temperature of the vapor is 25 degrees Celsius, what is the molecular weight of the vapor? (Assume the gas

  17. AP Chem

    Would someone please check these for me? 52. In an experiment, you fill a heavy-walled 5.00-L flask with methane gas, CH4. If the flask contains 7.13 g of methane at 19 degrees C, what is the gas pressure? 2.14 atm 56. A 2.50-L flask was used to collect a

  18. Chemistry

    Given: solubility (g/100g H2O) temp degrees celcius KBR 20 65 40 80 60 90 80 100 100 110 A solution containing 10.5g of KBr in 10g of H2O at 100 degrees celcius is cooled to 40 degrees celcius. A)calculate the g/100g H2O of KBr B)is the solution saturated

  19. Chemistry

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  20. algebra

    You are trying to compare the Farenheit and Celcius scales and you have two examples; Temperatur A is 50 degrees Celcius and 122 Farenheit. Temperature B is 100 degrees Celcius and 212 degrees Farenheit. What graph models the relationship between Farengeit

  21. Chemistry

    a solution of 4.65 of a carbohydrate in 100.0g of water has a density of 1.016g/mL and an osmotic pressure of 3.18 atm at 20.0 degrees celcius. calculate the molar mass of the carbohydrate.

  22. Chemistry

    3.25g of zinc was added to 50cm^3 of a 4.0 molar dm^-3 HCl. When the reaction was completed the temperature rose by 28 degrees celcius. (a) Is the reaction exothermic or endothermic? (b)All the zinc dissolve in this reaction. How many moles of zinc

  23. AP Chemistry

    Calculate the volume of a 36% solution of hydrochloric acid (density = 1.50g/mL, molar mass = 36 g/mol) required to prepare 9 liters of a 5 molar solution. A. 1 liter B. 2 liters C. 3 liters D. 4 liters E. 5 liters

  24. Chem

    The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product

  25. physics

    Ice at -10degrees celcius and steam at 130 degrees celcius are brought together at atmospheric pressure in a perfectly insulated container. After thermal equilibrium is reached,the liquid phase at 50 degrees celcius is present. Ignoring the container and

  26. Chemistry (Urgent)

    Ksp of PbI2 at 25 degrees celcius and 15 degrees celcius is 7.5×10^-8 and 7.5×10^-9 respectively. (Pb=207 I=127) 1) write an expression for the equilibrium of PbI2 2)write an equation for the Ksp of PbI2 3)calculate the solubility of PbI2 at 25 degrees

  27. AP Chemistry

    Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^-3. (A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius. (B) What will be the new equilibrium concentrations

  28. Physics

    A physicist converted 2 kg of water at 37 degrees celcius to steam at 100 degrees celcius. Assuming no heat is lost, calculate the amount of energy needed to heat to 100 degrees celcius.

  29. Chemistry

    calculate the amount of heat energy in joules to condense 125g of steam at 100 degrees celcius and cool to the liquid to 15 degrees celcius?

  30. Chem.

    Ethanol has a heat of vaporization of 38.56 KJ/Mol. And a normal boiling point of 78.4 degrees celcius. WHAT is the vapor pressure of ethanol at 18 degrees celcius?? Okay...I don't really get out to solve for it actually. ln (P2/760 torr)= -38560/8.3145 *

  31. chemistry

    Calculate the resulting pressure if 4.50 liters of nitrogen at 35 degrees Celsius and 790 torr and 3.7 liters of oxygen at 15 degrees Celsius and 750 torr are pumped into a 1.00 liters container at 25 degrees celsius. Assume ideal gas behavior.

  32. chemistry

    2SO2 + O2 = 2SO3 4.00 mols of SO2 5.00 mol of O2 in 2L of a container at 200 degrees celcius. Concentration of O2 is 2M calculate the Kc

  33. chemistry

    help me please i don't understand what to do... Calculate the molar entropy of vaporization for liquid hydrogen iodide at its boiling point -34.55 degrees celcius. HI(l) arrows pointing to both HI(g) Triangle H of vap= 19.76 kJ/mol

  34. Chemistry

    Regular gasoline (C8H18) reacts with oxygen gas to form carbon dioxide gas and water vapor. If your tanks of gasoline holds about 10.5 kg of gasoline, how many liters of carbon dioxide are formed at 24 degrees Celcius and 725mm Hg from the combustion of

  35. Chem 103

    a piece of gold is heated to 100 degrees celsius. A piece of copper is chilled in an ice bath to 0 degrees celsius. Both pieces of metal are placed in a beaker containing 150 g of water at 20 degrees celcius. Will the temperature of the water be greater

  36. physics

    4.A steel rod is heated to 200 degrees Celcius and is then rigidly clamped at both ends and allowed to cool. Determine the temperature at which the rod will break if the tensile strength, coefficient of linear thermal expansion and youngs modulus of

  37. chemistry

    calculate the molar weight of Freon-II, of 8.29 liters of its vapor at 200 degrees celcius and 790 mm Hg has a mass of 30.5 g.?

  38. Chemistry

    calculate the molar weight of Freon-II, of 8.29 liters of its vapor at 200 degrees celcius and 790 mm Hg has a mass of 30.5 g.

  39. CHEMISTRY

    I put down all the info that I found but I cant figure out the questions 1 & 2 at the bottom!! Empty Calorimeter- 11.6 g Room temp - 21 degrees celcius Three different experiments of 50mL 1(M) HCl reacts with 0.15 g Mg, 0.25g Mg, and 0.35g Mg respectively.

  40. chemistry

    A student breaks a thermometer and spills most of the mercury (Hg) onto the floor of a laboratory that measures 15.2 m long, 6.6 m wide, and 2.4 m high. (a) Calculate the mass of mercury vapor (in grams) in the room at 20 degrees celcius. The vapor

  41. chemistry

    1 ) A sample of vapor occupies a volume of 125 ml at 100 celcius and 748 torr. What is its volume under STP conditions? 2) A sample of vapor weighing 0.745 g filled a 250 ml flask when placed in a water bath at 98 degree celcius. The barometric presure

  42. Chemistry

    what is the relative humidity if there is .5 moles of water vapor per 100 liters of air at 40 degrees celcius?

  43. physics

    300 grams of led at 200 degrees celcius is dropped into 150 grams of water at 10 degrees celcius. if the final temperature is 20 degrees celcius, calculate the specific heat capacity of the led. (specific heat capacity of water is 4200 joules per kilogram

  44. Chemistry !

    The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product

  45. High school AP chem

    The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product

  46. chemistry

    What is the vapor pressure (in mm Hg) of a solution of 12.5 g of glucose ( C6H12O6) in 75.0 g of methanol (CH3OH) at 27 degrees celcius? The vapor pressure of pure methanol at 27 degrees celcius is 140 mm Hg.

  47. chemistry

    I have to calculate the vapor pressure of water at 25.0 degrees celicus. The heat of vaporization of water is 40.65 kj/mol and the vapor pressure of water is 92.7 Torr at 50 degrees celcius. I know I should use log10 P=A- B/C+T but I don't know how to work

  48. Organic chemistry

    A 200.0g sample of glucose(180.16g/mol, Kmp=1.86 degrees celcius/m, mp=146 degrees celcius)is contaminated with 5.000g of table salt, sodium chloride(58.44g/mol, mp=801 degrees celcius). What would the expected melting point of the mixture be?

  49. chemistry

    find the specific heat of lead using 200 g of pb at o degrees celcius and placing it in 200 g of water at 60 degrees celcius

  50. Chemistry

    How much heat energy is required to raise the temperature of 4.50 liters of water from 36 degrees celcius to 44.6 degrees celcius?

  51. college chem

    calculate the amount of energy (in kj) necessary to convert 457 g of liquid water from 0 Celecius to water vapor at 167 celcius. the molar heat of vaporization (Hvap) of water is 40.79 jk/mol. the specific heat for water is 4.187 j/g celcius and for steam

  52. chemistry

    What is the vapor pressure of a solution of 0.5mol of a non-volatile impurity x and 2.0 g of TaCl5 (L) at a temperature of 226 degrees celcius? The vapor pressure of TaCl5 (l) at 226 degrees celcius ,621mmHg

  53. CHEMISTRY HELP DESPERATELY NEEDDED!!!

    Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^-3. (A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius. (B) What will be the new equilibrium concentrations

  54. CHEMISTRY HELP STILL NEEDED PLEASE!!!

    Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^-3. (A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius. (B) What will be the new equilibrium concentrations

  55. CHEMISTRY HELP NEEDED A.S.A.P

    Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^-3. (A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius. (B) What will be the new equilibrium concentrations

  56. Chemistry

    Please help! I don’t know where to start and I need step by step on how to solve: A gaseous mixture inside a rigid steel vessel contains 75% CO2(g) and 25% H2O (g) by volume at 175 degrees Celcius and 225 kPa. The mixture is then cooled to 0 degrees

  57. Chemistry HELP! CONFUSED!

    How do you do this? please help. Thank you. A.) Suppose 2.5 grams of sodium hydrogen carbonate reacts with acetic acid, calculate how many liters of carbon dioxide gas will be produced at 22 degrees celcius and 1.10 atm. B.) Suppose 0.990 liters of carbon

  58. Chemistry

    Calculate the pressure, in atmospheres, of 2.80 moles helium gas in a 18.0 liters container at 24 degrees celcius.

  59. Thermochemistry Ap Chem homework

    Any help would be great, even if it is just a way to start or a formula. Calculate the heat necessary to convert 10.0 g of water (just melted) at 0 degrees Celcius to water at 20 degrees Celcius, assuming that the specific heat remains constant at 1

  60. physics

    A 2.8 kg gold bar at 99 degrees celcius is dropped into 0.21 kg of water at 23 degrees celcius What is the final temperature? Assume the specific heat of gold is 129 J/kg times degrees celcius. Answer in units of degrees celcius

  61. chemistry

    The new vapor pressure of a solution of 3.25g of an unknown compound in 22.35g of H2O is 114.9mmHg at 55 degrees Celcius. What is the molar mass of the unknown compound?

  62. Grade 12 Chemistry

    If 100g of zinc (c=377J/kg degrees celcius) at 95 degrees celcius is dropped into 60g of water contained in a 100g calorimeter (c=419J/kg degrees celcius) at 20 degrees celcius, what will the final temperature be?

  63. chemistry

    Methanol boils at 65Celcius. The vapor pressure of ethanol at 65Celcius is at 410 torr. for a mixture containing .200 mol of methanol and .100 mol of ethanlol (at 65 Celcius) calculate the: 1. partial pressure of each liquid 2. total vapor pressure of the

  64. chemistry

    a sample of vapor weighing 0.745 g filled a 250 ml flask when placed in a water bath at 98 degrees celsius. the barometric pressure that day was 753 torr. calculate the volume of the vapor at stp, and the weight of one mol of the volitile liquid

  65. chemistry

    a sample of vapor weighing 0.745 g filled a 250 ml flask when placed in a water bath at 98 degrees celsius. the barometric pressure that day was 753 torr. calculate the volume of the vapor at stp, and the weight of one mol of the volitile liquid

  66. chemistry

    Data: freezing point of pure cyclohexane: 6.0 degrees celcius Freezing point of unknown soluton: 1.6 degrees celcius weight of cyclohexane: 40.0231g=0.0400231 kg weight of unknown solute: 0.4872 g K_f_ of cyclohexane: -20.00 degrees Celciusx kg/mole

  67. Ochem

    What volume of eugenol will be present in 30 mL of distillate? The essential oil found in cloves, eugenol, can be isolated by steam distillation because it is insoluble in water and has a measurable vapor pressure at 100 °C even though it has a much

  68. physics

    A COPPER BLOCK ,MASS 500g AND AT 200 DEGREES CELCIUS GIVES OUT ENERGY AT AN AVERAGE RATE OF 50W. (i)what is temperature after 5 min ? (ii)how long will it take before its temperature drops to 50 degrees celcius

  69. Chemistry 1 HN

    Find the mass of iron heated to 85 degrees celcius that was added to 54.0 grams of water. The temperature of the water changed from 20 degrees celcius to 60 degrees celcius. The specific heat of the iron is 0.045 J/g degrees celcius

  70. Chemistry

    Calculate the molar entropy of vaporization for liquid hydrogen iodide at its boiling point -34.55 degrees celcius. HI(l) HI(g) deltaHvap = 19.76 kJ/mol

  71. chem

    While the pressure of 1.40L of gas is kept constant, its temperature is increased from 27 degrees Celcius to 177 degrees Celcius, How do I calculate the new volume?

  72. chemistry

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  73. Chemistry

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  74. chemistry

    calculate the heat energy required to raise the temperature of a 500 gram iron pipe from 25 degrees celcius to 100 degrees celcius

  75. physics

    The specific heat capacity is 1800 J/Kg/K .Calculate the amount of energy liberated when 7kg of the liquid cools from 70 Degrees Celcius to 35 degrees celcius

  76. physical science

    calculate the change in thermal energy when 120kg of sand warms from 10 degrees celcius to 90 degrees celcius

  77. AP Chemistry

    Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^-3. (A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius. (B) What will be the new equilibrium concentrations

  78. Thermochemistry please

    I really need help on this problem... ===================== Hydrocarbon Formula Delta H (kj/mol) 1,3-Butadiene C4H6(g) 111.9 a) calculate the fuel value in kJ/g for this compound and determine the percentage of hydrogen by mass. I've tried it for hours yet

  79. Chemistry

    How many joules (J) are needed to increase the temperature of 43.0g of aluminum from 25 degrees celcius to 50 degrees celcius? (Cp of Al=0.90J/g degrees of celcius) I also need the formula, data, and answer.

  80. Math

    An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius? I have no

  81. Math

    An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius? I have no

  82. physics

    A metal rod has a length of 4m at 50 degrees celcius and a length of 6m at 200 degrees celcius. What is it's length at 20 degrees celcius?

  83. chemistry

    At 29.6 degrees C, pure water has a vapor pressure of 31.1 torr. A solution is prepared by adding 86.7 g of "L" a nonvolatile nonelectrolyte to 390.0 g of water. The vapor pressure of the resulting solution is 27.6 torr. Calculate the molar mass of "L"

  84. chemistry

    A closed vessel with volume of 226.9mL initially contained air at 680.8mmHg at 16.5 degrees celcius. A sample of an organic liquid of mass 0.113g was injected into the flask which was then warmed to 124.9 degrees celcus causing all the organic liquid to

  85. chem - pressure

    A closed vessel with volume of 226.9mL initially contained air at 680.8mmHg at 16.5 degrees celcius. A sample of an organic liquid of mass 0.113g was injected into the flask which was then warmed to 124.9 degrees celcus causing all the organic liquid to

  86. General chemistry

    The density of the vapor of a compound at 95 degrees C and 827 mmhg is 7.41 grams/liter. Calculate the molecular weight.

  87. Food Chemestry

    A heat exchanger is used to warm apple cider using steam as the heat source. The cider is heated from an initial temperature of 4 degrees celcius to a final temperature of 65 degree celcius. The steam enters the heat exchanger as 50% quality steam and

  88. science

    A heat exchanger is used to warm apple cider using steam as the heat source. The cider is heated from an initial temperature of 4 degrees celcius to a final temperature of 65 degree celcius. The steam enters the heat exchanger as 50% quality steam and

  89. P-Chem

    The equilibrium constant K for the hydrolysis of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) and phosphate is 1.66X10^5 at 37 degrees celcius, and Standard Delta H is -20.1 kJ/mol. Calculate Standard Delta S for the hydrolysis at 37 degrees

  90. enthalpy change

    a bunsen burner flame takes 8 minutes to raise 250g of water from 20 degrees to 100 degrees celcius, when the water is in a beaker of mass 100g (c=0.67J/g degrees celcuius). How long will i take to raise the temperature of 200g of glycerin (c=2.43J/g

  91. Chemistry

    Calculate the amount of heat in joules required to heat 43 grams of water from 28 degrees celcius to the normal boiling point 100 degrees celcius

  92. Chemistry

    Calculate the specific heat of a metallic element if 314 jouldes of heat energy are needed to raise the temperature of a 50g sample from 25 degrees Celcius to 50 degrees Celcius?

  93. Chemistry

    2. A 3.37 gram sample of a nonvolatile nonelectrolyte ( no ions) is dissolved in 23.7 grams of hexane (C6H14) at 25.0 degrees calcius. The vapor pressure of pure hexane at this temperature is 438 tort, and the vapor pressure of the solution is 419.3 torr.

  94. physics

    What mass of steam initially at 125 degree celcius is needed to warm 250g of water in 100g beaker from 22 degrees celcius to 50 degrees celcius?

  95. chemical

    The vapor pressure of mercury at 77¢K is 0.0018 mmHg. The atomic weight of mercury is 200.6 g/mole. If the mercury vapor were allowed to reach equilibrium at this temperature in an enclosed space, what would be the mercury vapor concentration in the

  96. chemistry

    we add 100 ml of water at 20 degrees celcius to 10g of an unknown substance which is at 50 degrees celcius. The water ends up at 25 degrees celcius. how much heat was transfered?

  97. Chemistry

    The density of water at 17 degrees celcius is 0.998774g/mL and at 18 degrees celcius it is 0.998595 g/mL. Calculate the density of water at 17.7 degrees celcius?

  98. College Physics

    A 2.30-cm-thick wood floor covers a 4.0 m x 5.5 m room. The subfloor on which the flooring sits is at a temperature of 16.4 degrees celcius, while the air in the room is at 19.3 degrees celcius. What is the rate of heat conduction through the floor? Use

  99. chemistry

    determine the solubility in g/100 g water of A. KNO3 at 90DEGREE CELCIUS B. KBr at 80 degrees celcius C. Kl at 0degree celcius D. KCl at 40 DEGREE CELCIUS

  100. Math

    An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius?

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