1. INTRODUCTION TO PHYSICS

    Question A mixture of alcohol and water has the density 750 kg m 3.calculate the ratio in the mixture of alcohol to water by i.mass ii.volume

    asked by "CRYING"HELP PLEASE!!!,THIS CAN SAVE A SMILE on November 26, 2014
  2. Science

    A density bottle weigh 0.25and0.75 when filled with water and 0.65N when filled with alcohol . Calculate the volume of water and alcohol

    asked by Adama on May 13, 2016
  3. Physics

    A paperweight, when weighed in air, has a weight of W = 7.5 N. When completely immersed in water, however, it has a weight of Win water = 4.2 N. Find the volume of the paperweight.

    asked by pete on November 7, 2007
  4. maths

    A solution whose volume is 80% liters is made up of 40% of water and 60% of alcohol,When x liters of water is added the percentage of alcohol drops to 40% Find X

    asked by Eddypiller dreamer on April 18, 2017
  5. Chemistry

    If 567mL of water are added to a flask which already contains 1.440 L, what is the new volume of water in the flask? My work: 1.400L=1440mL 567mL=0.567L

    asked by Lia on August 31, 2014
  6. Chemistry 1002

    Over a period of time, the concentration of sulfuric acid in a lead storage battery of an automobile has decreased from 38 percent by mass(density=1.29 g/mL) to 26 percent by mass(1.19 g/mL). Assume the volume of the acid remains constant at 715 mL.

    asked by Jen on April 19, 2015
  7. Physics

    Suppose you have a perfectly spherical water tank with an inside diameter of 8.6 metres. If the drain at the bottom of the tank can't handle a hydrostatic pressure of more than 50 kilopascals, what is the maximum volume of water, in litres, that can be

    asked by Anna on April 17, 2008
  8. Physics

    Suppose you have a perfectly spherical water tank with an inside diameter of 8.6 metres. If the drain at the bottom of the tank can't handle a hydrostatic pressure of more than 50 kilopascals, what is the maximum volume of water, in litres, that can be

    asked by zahra on April 17, 2008
  9. Chemistry

    Suppose that you are planning a backpacking trip and will need to boil 40 L of water for your group. What volume of fuel should you bring? Assume each of the following: the fuel has an average formula of C7H16; 15% of the heat generated from combustion

    asked by Kristen on November 1, 2010
  10. chemistry

    Suppose that you are planning a backpacking trip and will need to boil 40 L of water for your group. What volume of fuel should you bring? Assume each of the following: the fuel has an average formula of C7H16; 15% of the heat generated from combustion

    asked by Anonymous on November 1, 2010
  11. Chemistry

    The solubility of salicilyc acid in water at 20C is .2g in 100mL. The solubility is salicilyc acid in boiling water is 6.67g in 100mL. Calculate the minimum volume of water needed to re-crystallize .550g of crude salicilyc acid.

    asked by Jessie on September 29, 2011
  12. Chemistry

    It says prepare a theoretical titration of 25 mL of 0.1037 M formic acid (HCOOH; pKa= 3.75) solution (diluted to 100mL volume with deionized water) by 0.0964 M solution of KOH. It asks to determine the volume of KOH solution needed to reach equivalence

    asked by Anonymous on October 25, 2010
  13. Chemistry

    How would you prepare 2.5 L of a 0.05 M solution of iron (III) chloride using iron (III) chloride hexahydrate Since 1 mol iron(III)chloride hexahydrate contains 1 mol iron(III) chloride, use the molar mass of the hexahydrate. M x L = grams/molar mass Solve

    asked by MEl on May 2, 2007
  14. science

    In 91% (by volume) isopropyl alcohol (a large [compared to water], flammable molecule) solution, there are only two substances: the alcohol, and water. So when I poured 50 mL of 91% isopropyl alcohol into a graduated cylinder, how many milliliters were

    asked by edward on February 6, 2012
  15. Math

    A farmer has two blends of grain, one 50% barley and the other 20% barley. How many pounds of each each blend should be used to create a 45 pound mix that is 30% barley ?

    asked by Jess on October 9, 2016
  16. physics

    A 1000 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the kinetic frictional force f_k between the boat and water is proportional to the speed v of the boat: f_k = 70v, where v is in meters per second and f_k is in newtons.

    asked by Kelsey on August 30, 2010
  17. college physics

    By immersing a crown in water its volume is 26inc^3=4.2x10^-4m^3. what would its weight be if it were pure gold? What would its weight be if its volume were half gold and half lead?

    asked by tiffany on October 1, 2012
  18. Plant Physiology

    Hey i have a mid term today at 3 , and this one sample question my prof posted online. If someone can please show me how to get the answers i would really appreciate it: A plant cell is found to have a Ψs = - 0.7 MPa and a Ψp = 0.5 MPa. Is this cell

    asked by Saira on February 13, 2009
  19. Calculus

    Water is leaking out of an inverted conical tank at a rate of 10,000 cm^3/min at the same time that water is being pumped into the tank at a constant rate. The tank has height 6m and the diameter at the top is 4m. If the water level is rising at a rate of

    asked by Anonymous on September 24, 2011
  20. Chen=mistry

    Sodium metal reacts violently with water to form NaOH and release hydrogen gas. Suppose that 3.00 g of Na reacts completely with 3.00 L of water and the final volume of the system is 3 L. What is the molarity M of the NaOH Solution formed by the reaction?

    asked by Janet on May 1, 2013
  21. chemistry

    peice of sodium metal reacts with water. 246ml volume of hydrogen gas was collected over water at 25 celsius and at an atmospheric pressuric pf 101.3 kpa. what was the pressure of dry hydrogen? what is the mass of sodium used up by the reaction?

    asked by Riana on January 29, 2013
  22. solid mensuration

    Find the volume of water in the horizontal tank if it is 7/8 full. Radius of the tank is 600mm. and the lenght of the tank is 5m. If the tank is place in a vertical position, what is the depth of water inside the tank?

    asked by leo on May 12, 2011
  23. college physics

    a 7500 kilogram rocket blasts off vertically upward from the launch pad with a constant acceleration of 2.25 m/s squared and feels no appreciable air resistance, when it reaches the height of 525 meter its engine suddenly fail so that the only force acting

    asked by kat on July 19, 2010
  24. calculus

    A reservoir is in the form og the frustum of a cone with upper base of radius 8ft and lower base radius of 4 ft and altitude of 10ft. The water in the reservoir is xft deep. If the level of the water is increasing at 4ft/min., how fast is the volume of

    asked by Light on April 27, 2013
  25. science

    A diesel engine's piston compresses 16 cm3 of fuel-air mixture into 1 cm3. The pressure changes from 1 atmosphere to 48 atmospheres. If the initial temperature of the gas was 305 K, what was the final temperature? Note: As long as the units for pressure

    asked by jasmine on June 21, 2011
  26. Social Studies

    Which of the following contributed to Britain's Industrial Revolution? A. Large Labor force C. powerful monarchy B. Decreasing food supplies D. decreasing money supply. The textile industry met its last major challenge to full mechanization with the

    asked by Erin on May 14, 2013
  27. Physics

    A 20% efficient real engine is used to speed up a train from rest to 7.0 m/s. An ideal (Carnot) engine using the same cold and hot reservoir would accelerate the same train from rest to a speed of 8.0 m/s using the same amount of fuel. The cold reservoir

    asked by Anonymous on June 16, 2016
  28. Physics

    At an antique car rally, a Stanley Steamer automobile travels north at 38 km/h and a Pierce Arrow automobile travels east at 51 km/h. Relative to an observer riding in the Stanley Steamer, what are the x- and y-components of the velocity of the Pierce

    asked by Max on February 11, 2010
  29. Chemistry

    I'm having trouble trying to figure out how to setup and solve these problems: 1) 2,600.0 mL of air is at 20.0C. What is the volume at 60.0C? 2) A gas occupies 900.0 mL at a temperasture of 27.0C. What is the volume at 132.0C? 3) What change in volume

    asked by Austin on March 19, 2014
  30. phys

    A cylinder in a car engine takes Vi = 4.50 10-2 m3 of air into the chamber at 30° C and at atmospheric pressure. The piston then compresses the air to 0.112 times of the original volume (0.112 Vi) and to 24.0 times the original pressure (24.0 Pi). What is

    asked by opp on April 25, 2012
  31. physics

    The efficiency of a machine is in general defined as the ratio between useful (released) energy and the input energy. Therefore, the exact formulas for efficiency depend on the purpose of the machine. What's the difference in the maximal efficiency of a

    asked by maths on July 9, 2013
  32. chemistry

    You add 9.1 of iron to 25.50 of water and observe that the volume of iron and water together is 26.66 . Calculate the density of iron.

    asked by mikael on January 23, 2013
  33. Chemistry

    2 moles of helium (He) are pumped from a gas canister into a weather balloon. The balloon at this point has a volume V1. 1 mole of nitrogen gas (N2) is added at the same temperature and pressure. The volume of the balloon changes to V2. How will the new

    asked by Colin on April 18, 2013
  34. Physics

    Water at room temperature flows with a constant speed of 8 m/s through a nozzle with a square cross section, as shown in the figure. Water enters the nozzle at point A and exits the nozzle at point B. The lengths of the sides of the square cross section at

    asked by mymi on November 7, 2011
  35. Physics

    Imagine a landing craft approaching the surface of Callisto, one of Jupiter's moons. If the engine provides an upward force (thrust) of 2784 N, the craft descends at constant speed; if the engine provides only 1879 N, the craft accelerates downward at 0.39

    asked by Kameron on March 3, 2016
  36. Accounting

    Buying a Coffee Company Buying a Coffee Company --- 10809 Q ACC Buying a Coffee Company Perking up Profits at Better Brew and Perfect Blend After years of dreaming about owning your own business, you decided that owning a coffee shop would be perfect.

    asked by Seyhun on April 19, 2009
  37. chemistry

    Calculate the word done in joules when 1.0 mile of water vaporizes at 1.0 atm and 100 degrees Celsius. Assume that the volume of liquid water is negligible compared with that of steam at 100 degrees celcius, and ideal gas behavior.

    asked by Anonymous on October 24, 2014
  38. chemistry

    Nitric acid can be produced by the reaction of gaseous nitrogen dioxide with water. 3NO2(g) + H2O(`) −! 2HNO3(`) + NO(g) If 745 L of NO2 gas react with water, what volume of NO gas will be produced? As- sume the gases are measured under the same

    asked by Aaron on February 8, 2012
  39. physics

    an object floats with 1/2 of its volume beneath the surface of the water. the weight of the displaced water=2000 N. what is the weight of the object?

    asked by john on March 21, 2010
  40. Chemistry

    When heated to 350. ∘C at 0.950 atm, ammonium nitrate decomposes to produce nitrogen, water, and oxygen gases: 2NH4NO3(s)→Δ2N2(g)+4H2O(g)+O2(g) Using the ideal gas law equation, calculate the volume, in liters, of water vapor produced when 21.8 g of

    asked by Telimm on June 29, 2015
  41. Chemistry please help

    104 ml of ethene, C2H4 is burned in 408 ml of oxygen, producing carbon dioxide and some liquid water. Some oxygen remain unreacted. Calculate the volume of carbon dioxide produced and the volume of oxygen remaining

    asked by Anonymous on September 11, 2014
  42. chemistry

    What is the percent by mass of 3.55 g NaCl dissolved in 88 g H2O? 2. A solution is made by adding 1.23 moles of KCl to 1000.0 g of water. What is the % by mass of KCl in this solution? 3. If you have 100.0 mL of a 25% aqueous solution of ethanol, what

    asked by Anonymous on February 11, 2011
  43. chemistry

    What is the percent by mass of 3.55 g NaCl dissolved in 88 g H2O? 2. A solution is made by adding 1.23 moles of KCl to 1000.0 g of water. What is the % by mass of KCl in this solution? 3. If you have 100.0 mL of a 25% aqueous solution of ethanol, what

    asked by Anonymous on February 11, 2011
  44. Chemistry

    A student makes a solution by dissolving 55.8 grams of potassium hydroxide in 875.0 grams of water. The resulting solution has a density of 1.07 grams per milliliter. 1. What is the volume of this solution? 2. Calculate the % concentration of this

    asked by Paul on January 31, 2011
  45. Chemistry

    24.5 ml of water are added to a 1.20 molar solution of nitric acid. If the concentration decreases to 0.55 molar, what volume of the concentrated solution was used? 1.20 M x mL = (24.5 mL + mL) x 0.55 M Solve for mL. Check my thinking. When you finish the

    asked by Veronica on April 20, 2007
  46. Physics

    Because gasoline is less dense than water, drums containing gasoline will float in water. Suppose a 220- L steel drum is completely full of gasoline. What total volume of steel can be used in making the drum if the gasoline-filled drum is to float in fresh

    asked by Hee on October 29, 2010
  47. Physics helppp

    Imagine a landing craft approaching the surface of the moon of a distant planet. If the engine provides an upward force (thrust) of 2980 N, the craft descends at constant speed; if the engine provides only 2200 N, the craft accelerates downward at 0.46

    asked by Sam on July 13, 2010
  48. Chemistry

    The volume of the nitrogen gas is 125ml atmospheric pressure is 763mm Hg Water temperature is 24 degrees Celcius. The water level inside the eudiometer is the same as the level of water in the beaker. Calculate the pressure of the dry nitrogen gas.

    asked by Maddy on April 9, 2015
  49. physics

    A car's internal combustion engine can be modeled as a heat engine operating between a combustion temperature of 1500∘C and an air temperature of 20∘C with 30% of the Carnot efficiency. The heat of combustion of gasoline is 47 kJ/g. Q) What mass of

    asked by Help on December 12, 2016
  50. PHYSICS

    A catapult launches a rocket at an angle of 56.9° above the horizontal with an initial speed of 100 m/s. The rocket engine immediately starts a burn, and for 3.25 s the rocket moves along its initial line of motion with an acceleration of 28.1 m/s2. Then

    asked by j on April 26, 2012
  51. Chemistry

    A eudiometer contains 65.0 ml sample of gas collected by the diplacement of water. The water levels inside and outside the eudiometer are the same. The atmospheric pressure is 92.5 kPa and the temperture is 23 degrees. What volume will the dry gas occupy

    asked by Lauren on January 16, 2008
  52. math

    Suppose we pump water into an inverted right-circular cone tank at the rate of 6 cubic feet per minute. The tank has the height 9 ft and radius on the top is 8 ft. What is the rate at which the water level is rising when the water is 3 ft deep? Leave the

    asked by Ravinder on November 13, 2012
  53. Gen Chemestry

    A 27.6 ml volume of chlorine gas is collected over water at 23 C and 750 torr. The mass of the gas is 78.4 mg. The vapor pressure of water is 21 torr. a) What is the pressure of the chlorine gas? b) How volume does the chlorine gas occupy? c) How many

    asked by Roth on October 25, 2008
  54. chemistry

    A typical bathtub can hold 106 gallons of water. Calculate the mass of natural gas that would need to be burned to heat the water for a tub of this size from 56 ◦F to 87 ◦F. Assume that the natural gas is pure methane (CH4) and that the products of

    asked by maria on October 26, 2013
  55. Chemistry

    1. A typical bathtub can hold 102 gallons of water. Calculate the mass of natural gas that would need to be burned to heat the water for a tub of this size from 63 ◦F to 98 ◦F. Assume that the natural gas is pure methane (CH4) and that the products of

    asked by Alex on October 26, 2015
  56. Science

    How can I triple the volume of water?

    asked by Stormie on September 11, 2007
  57. science

    what is the volume of water ? how do I describe this ?

    asked by ethan on November 10, 2009
  58. chemistry

    If I was 100% water what would my volume be?

    asked by stacy on January 22, 2011
  59. Physiology

    What is the volume of 0.23 kg of pure water?

    asked by Jerome on January 27, 2011
  60. biology

    If I was 100% water what would my volume be?

    asked by stacy on January 22, 2011
  61. chemistry

    The reaction between 0.0272 g of Mg with an excess of water was carried out in an ice calorimeter. The volume of water decreased by 0.19 mL during the reaction. a) Write the equation that occurs. Is it a redox? b) Calculate the enthalpy of reaction? i have

    asked by edward on November 16, 2009
  62. Science

    1. Density is the relationship between ____. (1 point) mass and volume cubic centimeters and pounds weight and volume grams and mass 2. Which of the following is NOT a possible sign of a chemical change? (1 point) a change in state a change in color the

    asked by HELPMEASAP! on April 16, 2013
  63. College Biology

    The RBC osmolarity of a patient is 300 mOsm/L and is given 1L of distilled water and starts with 3L of plasma. What is the plasma osmolarity after infusion mixes with plasma but before water enters her RBC? Once infused water equilibrated between plasma

    asked by Anonymous on January 30, 2011
  64. Physics

    An inflated balloon occupies a volume of two (2) liters. The balloon is tied with a string and weighted down with a heavy stone. What is its volume when it reaches the bottom of a pond 5.2 meters deep? Assume the atmospheric pressure is equal to 1

    asked by Ariannah on March 9, 2011
  65. Physics

    An object weighing 400.0g in air is immersed in water after being tied to a string connected to a balance. The scale now reads 364.6g. a.) Find the loss of weight(in gram of weight) when completely submersed in water. b.) Find the volume of the object in

    asked by Megan on December 5, 2012
  66. physics

    A Navy jet (see the figure) with a weight of 219 kN requires an airspeed of 87 m/s for liftoff. The engine develops a maximum force of 100 kN, but that is insufficient for reaching takeoff speed in the 85 m runway available on an aircraft carrier. What

    asked by John on February 26, 2015
  67. physics

    Imagine a landing carft approaching the surface of Callisto, one of Jupiture's moons. If the engine provides an upward force (thrust) of 3260 N, the craft descends at constant speed; if the engine provides only 2200 N the craft accelerates downward at .39

    asked by Bri on November 21, 2006
  68. physics

    (Densities of object 1 and 2 are greater than that of the fluid) 1. Object 1 and 2 have same volume and shape, but object 1 is more dense than object 2, which one has greater buoyant force?? 2. object 1 and 2 has same mass, but density of object 1 is

    asked by greg on October 27, 2006
  69. science

    Find out the volume of water required to make 91% sulphuric acid , sp gravity 1.81 from cons sulphuric acid of MW 98.08 and sp gravity 1.84?For one liter volume

    asked by u k shaw on October 10, 2018
  70. chemistry

    Temp - 650 Pressure - 690mm Hg mass - 0.927g volume - 194cm3 How do I calculate the volume of the gas? You have the volume, given. How do I calculate the volume at a different temperature?

    asked by bex on February 27, 2007
  71. college chem. please help!!

    Calculate the % empty space in 1 mole of water at 25 degree C (d=0.9971g/ml). The volume of a water molecule can be taken as the sum of the volumes of the 2 hydrogen molecules and the oxygen atom. Use the single bonded covalent radii of 37pm for hydrogen

    asked by christy on February 4, 2009
  72. college chemistry

    Calculate the % empty space in 1 mole of water at 25 degree C (d=0.9971g/ml). The volume of a water molecule can be taken as the sum of the volumes of the 2 hydrogen molecules and the oxygen atom. Use the single bonded covalent radii of 37pm for hydrogen

    asked by christy on February 4, 2009
  73. math

    two cylindrical tanks have the same height, but the radius of one tank equals the diameter of the other. if the volume of the larger is k% more than the volume of the smaller, k= ? a)50 b)100 c)200 d)300 e)400 small tank volume: pi*(r/2)^2*h big tank

    asked by Christine on June 23, 2005
  74. Physics (forgot to post this question #2)

    During the compression stroke of a certain gasoline engine, the pressure increases from 1.00atm to 20.0atm. If the process is adiabatic and the fuel air mixture behaves a a diatomic ideal gas a) by what factor does the volume change b) by what factor does

    asked by ~christina~ on March 26, 2008
  75. Chem

    A dilute aqueous solution of Na2SO4 is electrolyzed between Pt electrodes for 3.70 h with a current of 2.77 A . Part A What volume of gas, saturated with water vapor at 25∘C and at a total pressure of 742 mmHg , would be collected at the anode? The vapor

    asked by A on April 1, 2018
  76. Chem

    Can someone check these homework answers please? 32. The barometric pressure measured outside an airplane at 9 km was 259 mmHg. Calculate the pressure in kPa. 34.5 kPa 36. A diving bell is a container open at the bottom. As the bell descends, the water

    asked by Anna on November 12, 2008
  77. Chemistry

    A student makes a solution by dissolving 55.8 grams of potassium hydroxide in 875.0 grams of water. The resulting solution has a density of 1.07 grams per milliliter. 1. What is the volume of this solution? 2. Calculate the % concentration of this

    asked by Paul on February 1, 2011
  78. Chemistry

    A student makes a solution by dissolving 55.8 grams of potassium hydroxide in 875.0 grams of water. The resulting solution has a density of 1.07 grams per milliliter. 1. What is the volume of this solution? 2. Calculate the % concentration of this

    asked by Paul on February 1, 2011
  79. Chemistry

    A student makes a solution by dissolving 55.8 grams of potassium hydroxide in 875.0 grams of water. The resulting solution has a density of 1.07 grams per milliliter. 1. What is the volume of this solution? 2. Calculate the % concentration of this

    asked by Paul on February 1, 2011
  80. Physics

    An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +15.0 m/s2. At tl = 2.8 s the rocket engine is shut down and the sled moves with constant velocity v. At the 7800 m mark, the sled begins to accelerate at -7

    asked by Ab on September 13, 2015
  81. Science - Chemistry

    If vapour pressure of water is 17.5 torr at 20C, what is the water vapour pressure inside a bottle of 100 proof whiskey? 100 proof = 50% ethanol Total volume = 1 L Mass of ethanol = 394.5g Mass of water = 500g Density of ethanol = 0.789g/mL Moles of

    asked by Sara on December 31, 2015
  82. PHYSIC

    a solid aluminum ingot weighs 89N in air a)what is the volume b)the ingot is suspended from a rope and totally immersed in water. what is the tension in the rope(the apparent weight of the ingot in water)?

    asked by KELLY on July 20, 2010
  83. Chemistry

    Calculate the concentration, in molarity, of a solution prepared by adding 9 mL of water to 1 mL of 0.1 M HCl solution. If 2.0 mL of 0.010 M NaOH is mixed with enough water to make the total volume 8 mL, what is the molarity of the resulting solution?

    asked by Nico on October 3, 2011
  84. physic

    a solid aluminum ingot weighs 89N in air a)what is the volume b)the ingot is suspended from a rope and totally immersed in water. what is the tension in the rope(the apparent weight of the ingot in water)?

    asked by kris- on July 20, 2010
  85. Chemistry

    An empty beaker weighs 42.75 grams. When completely filled with water, the beaker and its contents have a total mass of 399.95 grams. What volume does the beaker hold Use d=1.00 g/ml as the density of water.

    asked by Elizabeth Morgan on September 8, 2012
  86. physics

    A solid ball with a mass m = 0.53 kg floats in a tank of water. The ball is made of material with a density of 400 . The density of water is 1000 . What fraction of the volume of the ball is below the waterline?

    asked by Anonymous on April 28, 2015
  87. maths

    A large pipe has a diameter of 9.8×10^2cm.Water flows in the pipe at a speed of 5m s^-1.Find the volume in m^3,of water that flows out from the pipe every second,correct to 2 significant fogures.[Take pai as 3.142]

    asked by ashley on January 12, 2014
  88. PHYSICS

    A solid ball with a mass m = 0.53 kg floats in a tank of water. The ball is made of material with a density of 400 kg/m3 . The density of water is 1000 kg/m3 . What fraction of the volume of the ball is below the waterline?

    asked by MONSOFT on April 3, 2015
  89. AP Chemistry

    1) Calculate the volume of air at 30 degrees C and 1.00 atm that is needed to burn completely 10.0 grams of propane. Assume that air is 21.0 percent O2 by volume. 2) Assuming all of the heat evolved in burning 30.0 g of propane is transferred to 8.00 kg of

    asked by OhGodChemistry on October 30, 2006
  90. physics

    The temperature in a room is kept at a constant 20 °C but the humidity is only 20%. If the room has a volume of 30m³, and the room’s door and windows closed, how many kilograms of water must be put into the vaporizer to increase the humidity from 20%

    asked by sand on January 4, 2012
  91. physics

    The temperature in a room is kept at a constant 20 °C but the humidity is only 20%. If the room has a volume of 30m³, and the room’s door and windows closed, how many kilograms of water must be put into the vaporizer to increase the humidity from 20%

    asked by sand on February 25, 2012
  92. physics

    The temperature in a room is kept at a constant 20 °C but the humidity is only 20%. If the room has a volume of 30m³, and the room’s door and windows closed, how many kilograms of water must be put into the vaporizer to increase the humidity from 20%

    asked by sand on February 27, 2012
  93. physics

    The temperature in a room is kept at a constant 20 °C but the humidity is only 20%. If the room has a volume of 30m³, and the room’s door and windows closed, how many kilograms of water must be put into the vaporizer to increase the humidity from 20%

    asked by sand on February 24, 2012
  94. Physics

    A jet aircraft is traveling at 180 m/s in horizontal flight. The engine takes in air at a rate of 77.0 kg/s and burns fuel at a rate of 3.15 kg/s. The exhaust gases are ejected at 595 m/s relative to the speed of the aircraft. Find the thrust of the jet

    asked by mymi on October 11, 2011
  95. Chemistry

    The reaction between 0.055 g of calcium with an excess of water was carried out in an ice calorimeter. The volume of water in the calorimeter decreased by 0.20 mL during the reaction. Calculate the enthalpy of the reaction (in kJ/mol).

    asked by Raj on November 24, 2007
  96. Pre Calculus

    The following table shows the rate of water flow (in L/min) through a dam. t (min) 1 5 9 13 17 21 25 V'(t) (L/min) 6 6 2 2 3 6 2 Approximate the total volume of water that passed through the dam from t=1 to t=25 using Simpson's rule, with n=6.

    asked by John on May 12, 2016
  97. Math

    The following table shows the rate of water flow (in L/min) through a dam. t (min) 1 6 11 16 21 26 31 V'(t) (L/min) 1 8 2 9 7 5 9 Approximate the total volume of water that passed through the dam from t=1 to t=31 using Simpson's rule, with n=6.

    asked by Steve on May 5, 2016
  98. science

    the teacher instructed three students A,B,and C respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50 g of NaOH in 100 ml of water B dissolved 50g of NaOH in 100g of water while C dissolved 50g of NaOH in

    asked by chemistry on September 6, 2011
  99. science

    the teacher instructed three students A,B,and C respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50 g of NaOH in 100 ml of water B dissolved 50g of NaOH in 100g of water while C dissolved 50g of NaOH in

    asked by irsha on September 6, 2011
  100. physics

    A cubical block of density rB and with sides of length L floats in a liquid of greater density rL. (a) What fraction of the block’s volume is above the surface of the liquid? (b) The liquid is denser than water (density rW) and does not mix with it. If

    asked by mary on February 4, 2016