1. math

    Find the number of decibels for the power of the sound given. Round to the nearest decibel. A rocket engine, 2.37 x 10−5 (10 to the -5 power) watts/cm2(squared)
  2. Science

    you are a patent agent, an inventor comes to you claiming he has invented a self-powered engine that requires no fuel to run. will you agree to patent this invention? why or why not? use the first law of thermodynamics. can anyone help me out with this?
  3. physics

    A 1000 kg car can accelerate from rest to a speed of 25 m/s in 10 s. What average power must the engine of car produce in order to cause this acceleration? Neglect friction losses
  4. General Chemistry I

    A sample of gas occupies a volume of 59.9 mL. As it expands, it does 126.2 J of work on its surroundings at a constant pressure of 798 torr. What is the final volume of the gas? a. 61.1 mL b. 1,250 mL c. 218 mL d. 1,490 mL e. None of the above I used the
  5. chemistry

    1 In the reaction of potassium permanganate and iron salt in acidic medium, how many moles of manganese reacted with iron? 2 moles of Mn with 1 mole of Fe 1 mole of Mn with 5 moles of Fe 1 mole of Mn reacts with 1 mole of Fe 5 moles of Mn reacts with 1
  6. General Chemistry : for Nursing

    Im Having a really Hard time with this problem :( ---> A sample containing 5.60g O2 gas has a volume of 31.0L . Pressure and temperature remain constant. 1 .) Oxygen is released until the volume is 8.00L . How many moles of O2 are removed?
  7. physics

    a 2.00 kg rock is dropped from a bridge to the water 50.0m below. what is the velocity as it hits the water? what is its kinetic energy as it hits the water?
  8. science

    andy mixed 40 ml of water at 15 degress celius with 40 ml of water at 65 degrees celius ..... what is the final temperature of the water.?? H E L P !
  9. Physics

    Please help! suppose you have some 20 degrees celsius water and some boiling water. How much of each would you use to make 4 kilograms of water at 45 degrees celsuis?
  10. Math

    If a water bottle holds 1.5 litters of water if I open a new bottle an drink half how much water is left
  11. Physic

    The spout heights in the container in the figure are 15 cm, 30 cm, 45 cm, and 60 cm. The water level is maintained at a 68 cm height by an outside supply. What is the speed of the water out of the 15 cm high hole? What is the speed of the water out of the
  12. chemistry

    2. Imagine you have two beakers. Both beakers are filled with the same amount of water. The water in both beakers is the same temperature as well. You add 50 g of Substance A to the first beaker, and 50 g of Substance B to the second beaker. After stirring
  13. Physics

    One gram of water is placed in a cylinder and the pressure is maintained at 2.0 x 105 Pa. The temperature of the water is raised by 31oC. Determine the change in internal energy when, a) the water is in its liquid phase and causes an expansion of 1.0 x
  14. Physics

    One gram of water is placed in a cylinder and the pressure is maintained at 2.0 x 105 Pa. The temperature of the water is raised by 31oC. Determine the change in internal energy when, a) the water is in its liquid phase and causes an expansion of 1.0 x
  15. Physics

    One gram of water is placed in a cylinder and the pressure is maintained at 2.0 x 105 Pa. The temperature of the water is raised by 31oC. Determine the change in internal energy when, a) the water is in its liquid phase and causes an expansion of 1.0 x
  16. Physics

    One gram of water is placed in a cylinder and the pressure is maintained at 2.0 x 105 Pa. The temperature of the water is raised by 31oC. Determine the change in internal energy when, a) the water is in its liquid phase and causes an expansion of 1.0 x
  17. statistics

    a batch of 25 used automobile alternators contains 3 defectives. if 3 alternators are sampled at random, find the probability of the event . (a). A=[none of the defectives appear ] (b). B=[exactly two defectives appear]
  18. math

    a group of friends shared the expenses of an automobile trip,which cost $40.if there had been 3 more people in the group.each would have $3 less.how many people were there in the group and how much did each pay?
  19. Science

    Salim added 1 g of salt to each of four beakers filled with water. He stirred the water at different speeds, and recorded how long it took for the salt to dissolved. Stirring - Time (sec) No stirring - 25 Slow stirring - 18 Medium stirring - 10 Fast
  20. Science

    Salim added 1 g of salt to each of four beakers filled with water. He stirred the water at different speeds, and recorded how long it took for the salt to dissolved. Stirring Time (sec) No stirring 25 Slow stirring 18 Medium stirring 10 Fast stirring 6
  21. business math

    Is it more economical to buy an automobile for $29,000 cash or to pay $4,500 down and $3,000 at the end of each quarter for 2 years, if the money is worth 8% compounded quarterly? What is the cash equivalent savings by picking the better plan?
  22. Physics

    An automobile accelerates 1.77 m/s2 over 6.00 s to reach freeway speed at the end of the entrance ramp. If the car's final velocity is 24.44 m/s, what is it's initial speed when it began accelerating. the answer i got was 35.06 m/s (35.1 m/s when doing sig
  23. AP Chem

    Can someone please check these problems? 34. You fill a balloon with helium gas to a volume of 2.68 L at 23 degrees C and 789 mmHg. Now you release the balloon. What would be the volume of helium if its pressure changes to 632 mmHg but the temperature is
  24. Quantitive Analysis

    You are asked to prepare 500. mL of a 0.250 M acetate buffer at pH 4.90 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer. Question 1: 1. How many grams of
  25. chemistry

    Which of the following statements is false ? a) S is negative when water condenses at 100oC b) Ssurroundings is positive when water condenses at 100oC c) Suniverse is equal to zero when water condenses at 990C d) Suniverse increases when water
  26. CHEM

    In a constant-pressure calorimeter, 60.0 mL of 0.340 M Ba(OH)2 was added to 60.0 mL of 0.680 M HCl. The reaction caused the temperature of the solution to rise from 24.07 °C to 28.70 °C. If the solution has the same density and specific heat as water,
  27. chemistry

    In a constant-pressure calorimeter, 55.0 mL of 0.310 M Ba(OH)2 was added to 55.0 mL of 0.620 M HCl. The reaction caused the temperature of the solution to rise from 22.23 °C to 26.45 °C. If the solution has the same density and specific heat as water,
  28. chemistry

    In a constant-pressure calorimeter, 60.0 mL of 0.310 M Ba(OH)2 was added to 60.0 mL of 0.620 M HCl. The reaction caused the temperature of the solution to rise from 23.44 °C to 27.66 °C. If the solution has the same density and specific heat as water,
  29. Chemistry

    In a constant-pressure calorimeter, 65.0 mL of 0.330 M Ba(OH)2 was added to 65.0 mL of 0.660 M HCl. The reaction caused the temperature of the solution to rise from 24.28 °C to 28.78 °C. If the solution has the same density and specific heat as water,
  30. Physics

    A straightforward method of finding the density of an object is to measure its mass and then measure its volume by submerging it in a graduated cylinder. What is the density of a 240-g rock that displaces 89.0 cm3 of water? (Note that the accuracy and
  31. Chemistry

    In a constant-pressure calorimeter, 60.0 mL of 0.310 M Ba(OH)2 was added to 60.0 mL of 0.620 M HCl. The reaction caused the temperature of the solution to rise from 22.19 °C to 26.41 °C. If the solution has the same density and specific heat as water,
  32. Chemistry

    In a constant-pressure calorimeter, 50.0 mL of 0.320 M Ba(OH)2 was added to 50.0 mL of 0.640 M HCl. The reaction caused the temperature of the solution to rise from 21.80 °C to 26.16 °C. If the solution has the same density and specific heat as water,
  33. Chemistry

    In a constant-pressure calorimeter, 50.0 mL of 0.320 M Ba(OH)2 was added to 50.0 mL of 0.640 M HCl. The reaction caused the temperature of the solution to rise from 23.47 °C to 27.83 °C. If the solution has the same density and specific heat as water,
  34. english

    sorry for posting it again i just need some help with proof read original thread display.cgi?id=1330379031 1. Water is the source of life. We all depend on it. Water is important, and we cannot survive a week without it. 2. Water should be free; it is a
  35. Chemistry

    A sample of 5.52 grams of NaOH is dissolved into 659 mL of aqueous 0.250 M NaOH (assume no volume change). This solution is then poured into 1.52 gallons of water. (You may assume that the two volumes can be added.) What is the concentration of NaOH in the
  36. Chemistry105

    1. (a) What is the molarity of a solution prepared by dissolving 4.315 g of NaOH in water to exactly 100 mL in a graduated flask? (Na = 23.0; O = 16.0' H = 1.0 amu).    (b) What volume of the above solution is required to neutralize exactly 25.00
  37. Chem

    Can you please tell me if these are right? A gas has a volume of 2.8 L at a temperature of 27 degrees C. What temperature degrees C is needed to expand the volume to 15 L? (P and n are constant.) I got 1334 degress C Combined gas law problem a balloon is
  38. Chemistry

    25.00 mL of heavy water (D2O where D is a hydrogen with a neutron in its nucleus) at 20 degrees C was pipetted into a 37.234 g beaker. The final mass of the beaker was 64.859 9 a- what is the density of heavy water at 20 degrees C b-The density of normal
  39. Physics

    a tourist drops 1-liter water filled balloon from the top of the Washington monument (170 m high).If air resistance is negligible and almost all the motion energy heats the water,find the increase in temperature of water when it hits the pavement?
  40. Physics

    a tourist drops 1-liter water filled baloon from the top of the Washington monument (170 m high).If air resistance is negligible and almost all the motion energy heats the water,find the increase in temperature of water when it hits the pavement?
  41. Thermodynamics

    12 kg of water in an insulated container is at 30 C. Initially, only 18 percent of the water is in the liquid phase. An electric heater, connected to a 120-V source and 9 A, is used to heat the system. Determine the time required to vaporize the entire
  42. Physics- Algebra based

    A diver springs upward from a board that is three meters above the water. At the instant she contacts the water her speed is 9.10 m/s and her body makes an angle of 80.0° with respect to the horizontal surface of the water. Determine her initial velocity,
  43. REALLY HARD CALCULUS PROBLEMMMM PLEASE HELP ME???

    A circular swimming pool has a diameter of 16 m, the sides are 3 m high, and the depth of the water is 2.5 m. How much work (in Joules) is required to pump all of the water over the side? (The acceleration due to gravity is 9.8 m/s 2 and the density of
  44. phys101

    in a calorimeter can(water equivalent=40g)are 200g of water and 50g of ice,all at 0 degreea celcius.into these poured 30g of water at 90degrees celcuis.what will be the final temperature of the system?specific capacity of water is 4186j/kg per degrees
  45. Calculus

    The temperature of a pan of hot water varies according to Newton's Law of Cooling: dT dt equals negative k times the quantity T minus A, where T is the water temperature, A is the room temperature, and k is a positive constant. If the water cools from
  46. Calculus

    while shopping for wine for his wedding, Kepler noticed that the price of a barrel of wine (here assumed to be a cylinder) was determined solely by the length d of a dipstick that was inserted diagonally through a hole in the top of the barrel to the edge
  47. Tech

    __________ is one of the few major indicators for which the ratio of production between the U.S. and China reflects the ratio of population size. A. Bicycle production B. Meat consumption C. Automobile production D. Fertilizer use im confused between A and
  48. chemistry

    1. A 123.00 liter sample of acetylene gas (C2H2) is reacted with excess oxygen at 27 C and 1 atm to produce carbon dioxide and water vapor. Calculate the following: a. The volume of CO2 produced at 1 atm and 400 C. b. The mass of H2O vapor produced.
  49. chemistry

    A student wanted to determine the density of an irregularly shaped piece of sodium metal. The student is warned not to use water displacement to find the volume of the piece of sodium. Explain the reason for the warning and offer an effective solution to
  50. Chemistry

    I will do an experiment that includes 4 grams of aluminum hydroxide and iron (III) oxide mixture, where 75% of it is Al(OH)3, and 15 ml of water and 25 ml of 2M KOH will be added and then boiled so that the Al(OH)3 dissolves. It will be filtered and then
  51. algebra

    At a crime scene, police officers find a murder victim in a tub full of warm water. A thermometer shows that the water temperature is 75 degrees F and the air temperature is 70 degrees F. It is known that most people fill a tub with water at 100 degrees F.
  52. Chemistry

    A flask was immersed in 350 g of water at 25 degrees C. Steam at 100 degrees C was passed into this flask, and eventually condensed into water at 100 degrees C. If the temperature of the water surrounding the flask was raised to 70 degrees C, how many
  53. geometry

    The volume of a cone is 54 pi cubic inches. The radius and height of the cone are both reduced by a factor of 3 to create a new cone. What is the volume of the new cone? Is the volume of the new cone 18pi cu in A. 2 pi cu inches B. 6 pi cu inches C. 9 pi
  54. Algebra

    The volume of a cone is 54 pi cubic inches. The radius and height of the cone are both reduced by a factor of 3 to create a new cone. What is the volume of the new cone? Is the volume of the new cone 18pi cu in A. 2 pi cu inches B. 6 pi cu inches C. 9 pi
  55. precalc

    According to an article by Thomas H. McMahon in the July 1975 issue of Scientific American, a tree’s height varies directly with the radius of the base of its trunk. He expressed this relation using the formula h = kr^2/3 where k is a constant, h is
  56. math

    Complete in Metric Conversions: What is the tip speed (ft/min) of a 21 inch long rotary lawn mower blade that is connected to the output shaft of an engine operating at 3400 rpm?
  57. Chem

    Calculate the expected volume of hot water that would be required to dissolve 0.15g of benzoic acid, vanillin, phthalic acid, salicyclic acid? You don't need to do all or any of them. I just need to know what formula to use and what to sub in and I can do
  58. chemistry

    Since October 2004, Jack Daniels Tennessee whisky, produced in Lynchburg, TN, has been bottled at 80 proof (40% alcohol by volume). Given that the density of ethyl alcohol is 0.789 g/cm3, and that of water 1.00 g/cm3, calculate the concentration of the
  59. physics

    The index of refraction of water for a given monochromatic light in water is n=4/3. The wavelength of this light in water is 500nm.  a) find the speed of this light in water.  b) find the energy of one photon of this light . Does this energy change if
  60. math

    an 8oz cup of water contains 7.5 x 10^24 water molecules. the ocean contains 5.4 x 10^46 water molecules. about how many cups of water are in the ocean.
  61. Science

    Say we have a jar of water, Is the angle of incidence, the angle that the the light enters the water, the angle above the water or the angle below the water?
  62. statistics

    11. You are taking a multiple choice examination that has 20 questions in a particular section with 5 possible answers for each question. You did not study for the test and you guessed the answers. The probability that you will get at least 50% of the
  63. Chemistry/lab math

    For an AST determination, 0.2 mL of serum was used. The change in absorbance (ΔA) was measured at 340 nm with a 3 mL reaction mixture. The initial reading was 0.54 A, the reading after 5 minutes was 0.32 A. Report the AST value in IU. Equation to use
  64. Bio

    Please Check my work and help me to answer the questions i could not get. Measure the cube that you are given. Complete the chart on the next page for your cube, then fill in the spaces for two other cubes, one measuring 1 cm on an edge and the other
  65. Bio

    Please Check my work and help me to answer the questions i could not get. Measure the cube that you are given. Complete the chart on the next page for your cube, then fill in the spaces for two other cubes, one measuring 1 cm on an edge and the other
  66. physics

    A tire with an inner volume of 0.0250 m3 is filled with air at a gauge pressure of 30.3 psi. If the tire valve is opened to the atmosphere, what volume outside of the tire does the escaping air occupy? Some air remains within the tire occupying the
  67. Physics please check

    The "karat" is a dimensionless unit that is used to indicate the proportion of gold in a gold-containing alloy. An alloy that is one karat gold contains a weight of pure gold that is one part in twenty-four. What is the volume of gold in a 20.0 karat gold
  68. math

    I need some serious help. I am a grade 10 student and I have this assignment due for tomorrow, but I can't get past the first question. The first part of the question asks me to calculate the volume of a box (prism) measuring 100mm by 60mm by 40mm. I got
  69. Precalc

    According to an article by Thomas H. McMahon in the July 1975 issue of Scientific American, a tree’s height varies directly with the radius of the base of its trunk. He expressed this relation using the formula h = kr^2/3 where k is a constant, h is the
  70. Chemistry

    A student mixed 75.0 mL of water containing 0.75 mol HCI at 25* C with 75.0 mL of water containing 0.75 mol of NaOH at 25*C in a foam cup calorimeter. The temperature of the resulting solution increased to 35*C. How much heat in kilojoules was released by
  71. physics

    the mass of the water is 131 kg and its initial temperature is 24.2°C, how much energy must the water transfer to its surroundings in order to freeze completely? The specific heat of water is 4186 J/kg·K, and the latent heat of fusion is 333 kJ/kg
  72. 10th grade chemistry

    We're doing a lab report on the hardness of water, and one of the calculations is "The EDTA reacts with the hard water ions in a 1:1 mole ratio. Calculate the molarity of the ions present in 20 mL of water tested." How would you do this?
  73. Physical Sciences

    A small water tank which holds 5000 litres of water is filled with a pump in 10 minutes. The tank is 30m above the ground. Calculate the increase in gravitational potential energy of the water.
  74. Math

    The volume of a cylinder is given by formula V= pi(3.14) r^2h where r is base radius and h is height a) the height of a cylinder of radius 5cm and volume 500. Cm^3 B) radius of base of a cylinder of volume 300 cm^3 and height 10 cm Our teacher didn't
  75. Phyics

    Water drips from a faucet into a flask at the rate of two drops every 2 seconds. A cubic centimeter (cm3) contains 20 drops. What volume of water, in cubic decimeters (dm3), will be collected in 3 hours? 3600 seconds in one hour 10800 seconds in three
  76. geometry!

    The swimming pool that sunny goes to has dimensions 20 meters long, 8 meters wide and 3 meters deep. What is the volume of water (in m^3) that the swimming pool contains?
  77. math

    The swimming pool that Calvin goes to has dimensions 20 meters long, 8 meters wide and 3 meters deep. What is the volume of water (in m3) that the swimming pool contains?
  78. maths

    The dimeter of a pool is 8 metres,the pool is 2 metres deep,what wiil be the volume of the water needed (in litres) needed to fill the pool
  79. Calculus

    4. At time t, t>0, the volume of a sphere is increasing at a rate proportional to the reciprocal of its radius. At t = 0, the radius of the sphere is 1 and at t = 15 the radius is 2. a. Find the radius of the sphere as a function of t. b. At what time t
  80. physics ( math)

    Solve the Equations in terms of X: a. x/a = b/c b. s=xt^2/2 d. 4= 10/x e. 5= 5/x-5 f. 40=2((x10)2-5) g. x(y+2)/ (5y +8) 1.What is the average of 2/9 and 4/5? 2. Subtract 4.20 x 10^-5 from 6.468 x 10^-4 3.Given: D= density; M= Mass; V= Volume; and D= M/V a)
  81. Maths

    A right circular cone of base radius 5 cm and depth 20 cm is held with its vertex downwards. If water is leaking through a small hole in the vertex at the rate of 8 cm^3/s, find the rate of change of the water level in the cone when the radius of the water
  82. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  83. Physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  84. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  85. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  86. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  87. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  88. physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  89. Physics

    A vertical tube with a tap at the base is filled with water, and a tuning fork vibrates over its mouth. As the water level is lowered in the tube, resonance is heard when the water level has dropped 18 cm, and again after 54 cm of distance exists from the
  90. Math

    1. What is the scale factor of a cube with volume 1331^3 to a cube with volume 85184^3? A) 121:1,936 B) 1:64 C) 4:1 D) 1:4 I'm not really quite sure how to do this question, but I got 1:4, is that correct?
  91. Chemistry

    A gas at a temperature of 95 degrees C occupies a volume of 159 mL. Assuming constant pressure, determine the volume at 15 degrees C.
  92. chemistry

    A sample of argon gas occupies a volume of 295ml at 36 C. What volume will the gas occupy at 55 assuming constant pressure?
  93. Algebra

    Pressure acting on 30 m^3 of a gas is reduced from 2 to 1 atmospheres. What new volume does the gas occupy? (Boyles law) What if it is increased from 1 to 2? What new volume?
  94. Geometry

    Given a cube with a volume of 18 cm3, what is the volume of a square pyramid that can fit perfectly inside the cube? this would be 6cm^3, right? since 3√18 is 6?
  95. chemistry

    A sample of gas at 80°C is cooled by 30 degrees until its final volume is 1.75 L. If the pressure remains constant, what was the initial volume of the gas.
  96. Chemistry

    If a sample of gas occupies a volume of 2.50 liters at 25.0 degrees C, would the volume be larger or smaller if the temperature drops to -5.0 degrees C?
  97. chemistry

    A sample of argon gas occupies a volume of 950 mL at 25.0°C. What volume will the gas occupy at 50.0°C if the pressure remains constant?
  98. maths

    1. A cone justs fits inside a cylinder with volume 300cm^2. what is the volume of the cone?Give reasons for your answers.
  99. Volume of a solid - calculus

    Find the volume of the solid generated by revolving the region bounded by the curves: y=2 Sqrt(x), y=4, x=0 about the x-axis
  100. Chemistry

    A gas occupies a volume of 140 mL at 35 degrees celcius and 97 kPa. What is the volume of the gas at STP? Please show the work.