1. chemistry

    The pKb of ammonia solution, NH3(aq) is 4.76. A buffer solution contains NH4Cl and NH3, has a pH of 9.45, and a total ammonia concentration (all forms) of 0.400 M. What is the concentration of NH4+? (Hint: [NH4+] + [NH3] = 0.400 M)

    asked by Anonymous on May 6, 2013
  2. reading

    Claim: Lead in drinking water will harm humans Which of the following pieces of data will be best evidence to support this claim?After using water that contains high levels of lead, people started experiencing joint pain. b. After using water that contains

    asked by ubah on May 18, 2018
  3. chemistry

    Instant cold packs, often used to ice athletic injuries on the field, contain ammonium nitrate and water separated by a thin plastic divider. When the divider is broken, the ammonium nitrate dissolves according to the following endothermic reaction:

    asked by savannah on December 19, 2012
  4. chemistry

    When I have the table filled out, what would I need to do in order to calculate the solubility product for calcium hydroxide? The following is what I have in mind, please tell if I am incorrect or correct. Ksp = [Ca+2][OH-1]2 You should have an average

    asked by Jessica on April 3, 2008
  5. Chemistry

    1. A small piece of zinc reacts with dilute HCl to form H2, which is collected over water at 16°C into a large flask. The total pressure is adjusted to barometric pressure (752 torr), and the volume is 1538 mL. Use Table 5.2 to help calculate the partial

    asked by Carter on October 18, 2010
  6. 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

    asked by Sam on May 25, 2009
  7. chemistry

    5ml of 8N Hn03, 4.8ml of 5N hcl and a certain volume of 17M h2s04 are mixed together and made up to 2 liter. 30ml of this acid mixture exactly neutralizes 42.9ml of na2c03, 10 h20 in 100ml of water .Calculate the amount of sulphate ion in gm present in

    asked by Fai on January 27, 2013
  8. AP Chem

    The formula for epson salts is MgSO4*7H2O. If 1.250 g of the compound is dissolved in water, calculate the number of milliliters of 0.200 M Ba(NO3)2 that would be required to precipitate all of the sulfate ions as barium sulfate. Make the same

    asked by Melissa on February 3, 2011
  9. Chemistry

    Nitric acid is commonly purchased as a 16 M solution, which has a density of 1.41 g/mL. Convert this molarity to a) mass percentage, b) molality, c) mole fraction. A) 16molHNO3(63.02HNO3/1MolHNO3)=1,008.32gHNO3 - 1,000gH20(1MolH20/1.41ml/g)=1410ml/mol w/w=

    asked by Michael on May 27, 2013
  10. Physics

    You dip your finger into a pan of water twice each second, producing waves with crests that are separated by 0.15 m. a) determine frequency of these water waves in units of Hz?? b) determine the period of these water waves in units of s. ?? c) determine

    asked by Bob on February 25, 2009
  11. Chemistry- Acids and Buffers

    Cyanic Acid is a weak acid HOCN + H2O H3O+ +OCN- ka= 3.5*10^-4 a) if 2.5ml of 0.01 M cyanic acid solution is added to 25.0 ml of a formis acid buffer with ph = 3.70, what is the ratio of [OCN-]/[HOCN] in the resulting solution? b) determine the pH of a

    asked by Tasneem on April 9, 2012
  12. critical thinking

    what is the rhetorical device for: What is the difference between "sugar free" and "no sugar added"? sugar free means no sugar at all and non sugar added means it has natural sugar nd they don't add any extra bob do you know what the rhetorical device used

    asked by christine on February 8, 2007
  13. Physics, Science

    A 26 kg block is connected to an empty 1 kg bucket by a cord running over a frictionless pulley. The coefficient of static friction between the table and the block is 0.435 and the coefficient of kinetic friction between the table and the block is 0.320.

    asked by Shae on October 4, 2010
  14. physics

    a sluice gate consists of a quadriant of a circle of radius 1.5m pivoted at its center 0. When the water is level with the gate, calculate the magnitude and direction of the resultant hydrostatic force on the gate and the moment required to open the

    asked by shu on January 14, 2016
  15. Chemistry

    Help needed with a calorimeter lab. I have to measure the enthalpy of a neutralization reaction between NaOH and HCl as well as find the concentration of NaOH the following ways. - using the mass and volume of NaOH - Using calorimetric data assuming no

    asked by Bibi on November 17, 2014
  16. Science please help

    Some of the water flows over the dam and is converted to energy, some water evaporates into the air. What spheres does the water, or hydrosphere interact with this example? a. Geosphere and atmosphere B. Atmosphere and biosphere C. Crysophere and

    asked by Steph on January 12, 2015
  17. Chemistry

    the heat of fusion water is 335J/g,the heat of vaporization of water is 2.26kJ/g, the specific heat of water is 4.184J/deg/g. how many grams of ice at 0 degrees could be converted to steam at 100 degrees C by 9,574J

    asked by Randy on April 28, 2012
  18. chemistry

    What is the predicted change in the boiling point of water when 4.00 g of barium chloride (BaCl2) is dissolved in 2.00 kg of water? Kb of water = 0.51°C/mol molar mass BaCl2 = 208.23 g/mol i value of BaCl2 = 3 A. 0.0016°C B. -0.0049°C C. -1.0°C D.

    asked by lu on January 23, 2017
  19. science

    Erin must perform a science experiment. She needs to dissolve 10 g of salt in 250 ml of water. She measures the water incorrectly and dissolves the 10 g of salt in 350 ml of water. Now she has no more salt. Explain what Erin can do to make the solution

    asked by astrid on April 29, 2008
  20. Chemistry

    Although water and ammonia differ in molar mass by only one unit, the boiling point of water is over 100 degrees C higher than that of ammonia. What forces in liquid water that do not exist in liquid ammonia could account for this observation?

    asked by Joe Schmo on April 28, 2011
  21. Can anyone help me with a physics question?

    A water tank has a volume of 100m^3. A square pipe leading to a pump is designed to completely replace all water in 20 minutes. Caluclate the length of a side of the square if the water is travelling at 5.0m/s through the square pipe.

    asked by Rob on March 17, 2010
  22. math

    A water system of 2 in.(inside diameter) pipe, having a length of 1/4 mile, is to be flushed with a volume of water equal to twice that contained in the system. how much water (gallons) must be flushed through the system? (note: one cubic foot=7.481gal.)

    asked by Wilfredo on February 11, 2013
  23. chemistry 1st year, for midterm help

    Hi, Can any1 help with theses questions. I need to solve these because there will be similar questions on the midterm for me, coming week. Btw I have tried few. 1. How many milliliters of a 15.0%, by mass solution of KOH (Aq) ( d= 1.14g/mL ) are required

    asked by ur class fella on February 12, 2009
  24. Chemistry

    Consider the following reaction AgNO3 (aq) + NaCl (aq) → AgCl (s) + NaNO3 (aq) DH = -66 kJ Suppose that 100.0 mL of 0.100M AgNO3 is added to 200.0 mL of 0.100 M NaCl in a coffee cup calorimeter. Assuming that the initial temperature of the solution is

    asked by Mahnoor on November 16, 2014
  25. chemistry

    While researching energy values of fuels, a chemist designed an experiment to find out the heat of combustion of pentane. Using the known hexane heat of combustion of hexane = 4650kJ/mol and the data below calculate the heat of combustion of pentane. Set

    asked by sarah on March 28, 2010
  26. chemistry

    While researching energy values of fuels, a chemist designed an experiment to find out the heat of combustion of pentane. Using the known hexane heat of combustion of hexane = 4650kJ/mol and the data below calculate the heat of combustion of pentane. Set

    asked by sarah on March 28, 2010
  27. algebra

    Rebecca drinks at least 7 cups of water each day. So far,she drank 1.5 cups. She will drink the rest of her water from a bottle that holds 1.5 cups. Write an inequality for the minimum number of bottles of water she will drink.

    asked by Anonymous on April 4, 2013
  28. Math

    PLEASE HELP: A bathtub has a capacity of 42 gallons and is completely full of water. Ten gallons of water are drained out. Enter the percentage of gallons of water left in the bathtub. Round your answer to the nearest hundredth.

    asked by jwalkerjess on September 17, 2015
  29. Science

    In an experiment, 200 g of aluminum at 100degrees celsius is mixed with 50.0g of water at 20.degrees celsius, with the mixture thermally isolated.(a)What is the equilibrium temperature?What are the entropy changes of(b)the aluminum,(c)the water,and(d)the

    asked by lungi on August 23, 2010
  30. algebra

    Rebecca drinks at least 7 cups of water each day. So far,she drank 1.5 cups. She will drink the rest of her water from a bottle that holds 1.5 cups. Write an inequality for the minimum number of bottles of water she will drink.

    asked by Anonymous on April 4, 2013
  31. Trigonometry

    The depth d in feet of the water in a bay at is given by d(t) = 3/2 sin (5πt/31) + 23 where t is time. Graph the depth of the water as a function of time. What is the maximum depth of the water to the nearest tenth of a foot? (Enter only the number.)

    asked by Mariah on October 2, 2014
  32. chem

    Calcium metal and water produce hydrogen gas. If the volume of wet gas collected over water is 95.0 mL at 20 °C and 758 mm Hg, what is the volume of dry gas at STP conditions? (The vapor pressure of water at 20 °C is 17.5 mm Hg.)

    asked by nurse on April 4, 2013
  33. physics

    A person jumps off a diving board 4.6 m above the water's surface into a deep pool. The person's downward motion stops 1.6 m below the surface of the water. Estimate the average deceleration (magnitude) of the person while under the water.

    asked by Anonymous on January 9, 2012
  34. physics

    A jet of water squirts out horizontally from a hole near the bottom of the tank, as seen in the figure below. Assume that y = 1.19 m and x = 0.544 m. What is the speed of the water coming out of the hole? The hole has a diameter of 3.06 mm. What is the

    asked by Jackie on March 5, 2012
  35. reading

    Please help Claim lead in drinking water with harm humans Which of the following is support this claim a. After use water that contain high level of lead, people note that their toothbrush turned yellow b. After use water that contain high level of lead,

    asked by lan on March 26, 2018
  36. calculus

    A water trough is 8m long and its cross-section is an isosceles triangle which is 60cm wide at the top, and the height is 60cm. The trough is not full. Give an expression for V, the volume of water in the trough in cm^3, when the depth of the water is d

    asked by Teresa on October 16, 2017
  37. physics

    A fire hose ejects a stream of water at an angle of 32.2 ° above the horizontal. The water leaves the nozzle with a speed of 26.5 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by louis aaaa on June 23, 2013
  38. Physics

    A fire hose ejects a stream of water at an angle of 29.0° above the horizontal. The water leaves the nozzle with a speed of 31.0 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Anonymous on September 19, 2012
  39. physics

    A fire hose ejects a stream of water at an angle of 35.0º above the horizontal. The water leaves the nozzle with a speed of 25.0 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by paul on September 20, 2013
  40. physics

    A fire hose ejects a stream of water at an angle of 38.3 ° above the horizontal. The water leaves the nozzle with a speed of 29.5 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by chelsea on January 31, 2012
  41. physics

    A fire hose ejects a stream of water at an angle of 31.5 ° above the horizontal. The water leaves the nozzle with a speed of 24.3 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by ray on September 19, 2012
  42. physics

    A fire hose ejects a stream of water at an angle of 31.7 ° above the horizontal. The water leaves the nozzle with a speed of 29.2 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Kristyn on March 26, 2015
  43. physics

    A fire hose ejects a stream of water at an angle of 31.7 ° above the horizontal. The water leaves the nozzle with a speed of 29.2 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Kristyn on March 25, 2015
  44. physics

    A fire hose ejects a stream of water at an angle of 36.4 ° above the horizontal. The water leaves the nozzle with a speed of 20.1 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Allyson on September 11, 2013
  45. physics

    A fire hose ejects a stream of water at an angle of 33.4 ° above the horizontal. The water leaves the nozzle with a speed of 20.1 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by V on February 5, 2015
  46. Physics

    A fire hose ejects a stream of water at an angle of 30.9° above the horizontal. The water leaves the nozzle with a speed of 26.5 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Cetris on February 28, 2015
  47. maths

    A water tank has the shape of a rectangular prism of base 50 cm2. This tank is being filled at the rate of 12 liters per minutes. Find the rate at which the height of the water in the water tank increases; express your answer in millimeters per second.

    asked by LARA on February 3, 2014
  48. chemistry

    A piece of metal weighing 26g is immersed in a quantity of water in a graduated cylinder. The initial volume of the water was 16.0 ml and volume of water plus metal is 22.0 ml. The density of metal in g/ml is? If you get this right i will hand you over my

    asked by Noel on July 22, 2010
  49. Math

    A rectangular glass tank is half filled with water. The measurements of the tank are 30cm in height, 25cm in length and 20cm in width. How many litres of water will raise the water level in the glass tank by 5cm?

    asked by Kate on September 12, 2017
  50. Physics/trig

    A fire hose ejects a stream of water at an angle of 33.6 ° above the horizontal. The water leaves the nozzle with a speed of 29.6 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Jenna on October 9, 2015
  51. math

    points) You arrive home to find that your 55 foot by 20 foot basement has 6 inches of water in it. a) If 1 cubic foot of water is about 7.48 gallons, how much water will you be pumping out of your basement? Express your answer rounded to the nearest tenth

    asked by joie on September 24, 2017
  52. Physics

    A fire hose ejects a stream of water at an angle of 35.8 ° above the horizontal. The water leaves the nozzle with a speed of 21.9 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the

    asked by Nicole on December 14, 2015
  53. Chem17

    Consider the following reaction at equilibrium: C(s) + H2O(g) CO(g) + H2(g) Predict which of these stresses which cause the equilibrium system to shift towards the reactant side (to the left). (There may be more than one correct answer - choose ALL of the

    asked by Ryan on May 3, 2011
  54. math

    Inside a long empty cylinder with radius R = 25 cm is put a long solid cylinder with radius r = 10 cm such that the bases of the two cylinders are attached. Then water is poured in the remaining empty region of the first cylinder until the height of the

    asked by emy on February 22, 2015
  55. Chemistry

    A 14.0-g sample of ice at -18.0°C is mixed with 122.0 g of water at 87.0°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J/g · °C, respectively, and

    asked by Janesa on March 9, 2012
  56. biology

    A 28.0-g sample of ice at -18.0°C is mixed with 124.0 g of water at 85.0°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J/g · °C, respectively, and

    asked by layla on October 15, 2011
  57. Chemisrty

    A 10.0 g sample of ice at -14.0°C is mixed with 124.0 g of water at 81.0°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J/g°C, respectively, and the

    asked by Nancy on December 10, 2012
  58. Chemistry

    A 19.6 g sample of ice at -10.0°C is mixed with 100.0 g of water at 75.4°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J g-1 °C-1, respectively,

    asked by Anonymous on November 23, 2010
  59. Chemistry

    A 13.0-g sample of ice at -13.0°C is mixed with 112.0 g of water at 80.0°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J/g · °C, respectively, and

    asked by Katrina on February 13, 2011
  60. chemistry

    A 13.0-g sample of ice at -13.0°C is mixed with 105.0 g of water at 78.0°C. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The heat capacities of H2O(s) and H2O(l) are 2.08 and 4.18 J/g · °C, respectively, and

    asked by layla on October 15, 2011
  61. Science: Chemistry

    Pentane (C5H12) burns in oxygen to produce carbon dioxide and water. C5H12(g)+8O2(g)→5CO2(g)+6H2O(g) Calculate the mass of CO2 that can be produced if the reaction of 38.5 g of pentane and sufficient oxygen has a 58.0 % yield.

    asked by Alex on November 16, 2015
  62. Physics - URGENT

    A ball is thrown horizontally of a cliff. If the initial speed of the ball is 17 m/s and the cliff is 77 m high, how far from the base of the cliff will the ball land in the water below? Calculate the answer in meters (m) and rounded to three significant

    asked by Anonymous on September 16, 2015
  63. Health Finance

    Question Details Consider the following 2007 data for Newark General Hospital (in millions of dollars): Static Flexible Actual Budget Budget Results Revenues $4.7 $4.8 $4.5 Costs 4.1 4.1 4.2 Pro?ts 0.6 0.7 0.3 a. Calculate and interpret the pro?t variance.

    asked by molamidi on January 26, 2012
  64. Chemistry-DrBob222

    A 1.0 L ball containing Ar at 5 atm is connected to a 10.0 L ball containing N2 at 2atm. A)Calculate the partial pressures and mole fractions of Ar and N2 after the valve is opened and the gases are allowed to mix (they fill the balls on both sides). My

    asked by Nevaeh on March 12, 2016
  65. Chemistry-DrBob222

    A 1.0 L ball containing Ar at 5 atm is connected to a 10.0 L ball containing N2 at 2atm. A)Calculate the partial pressures and mole fractions of Ar and N2 after the valve is opened and the gases are allowed to mix (they fill the balls on both sides). My

    asked by Student on March 11, 2016
  66. Chemistry

    A 1.0 L ball containing Ar at 5 atm is connected to a 10.0 L ball containing N2 at 2atm. A)Calculate the partial pressures and mole fractions of Ar and N2 after the valve is opened and the gases are allowed to mix (they fill the balls on both sides). My

    asked by Nevaeh on March 12, 2016
  67. physics

    A rock climber stands on top of a 56m -high cliff overhanging a pool of water. He throws two stones vertically downward 1.0s apart and observes that they cause a single splash. The initial speed of the first stone was 2.5(m/s) How long after the release of

    asked by Nicole on October 3, 2012
  68. Chemistry

    The lab we are doing is: Determining the ENTHALPY of a Chemical Reaction. There are three reactions. Reaction 1: NaOH + HCl, Reaction 2: NaOH + NH4Cl, and Reaction 3: HCl + NH3. I found the max temp, initial temp, and temp change of each reaction. Can you

    asked by Rina on October 30, 2017
  69. CHEMISTRY

    A 1.575 g sample of ethanedioic acid crystals, H2C2O4. xH20 was dissolved in water and made up to 250cm^3 . One mole of the acid reacts with two moles of NaOH. In a titration, 25.0 cm^3 of this solution of acid reacted with exactly 15.6 cm^3 of 0.160 mol/

    asked by Jack on July 9, 2016
  70. chem

    what happens when NaCl(s) is dissolved in water? (1)Cl-ions are attracted to the oxygen atoms of the water (2)Cl-ions are attracted to the hydrogen atoms of the water. (3)Na+ions are attracted to the hydrogen atoms of the water. (4)no attractions are

    asked by Tina on February 14, 2011
  71. Chemistry

    When a balloon filled with 1.249 g of hydrogen explodes, the hydrogen reacts with 9.99 g of oxygen to form water vapor. Assuming water vapor is the only product formed, how much water vapor is produced?

    asked by Jackie on March 25, 2016
  72. math,eng,phy,chem,bio,geography,economics

    in an experiment of oxgen to hydrogen in water molecule. 9g of iron were heated in a current of hydrogen,6.5g of iron and 2.8g of water were formed using this data. determine the proportion by mass of oxygen to hydrogen in water

    asked by joyce on January 17, 2016
  73. chemistry

    a 100.00 mL sample of water has an initial temperature of 20.0 degrees C. The water is heated, and after 5 minutes its temperature is 50 degrees C. approximately how much energy was absorbed by the water? (the specific heat of wter is 4.18 J/g. degrees C

    asked by kelly on September 4, 2011
  74. MMSS

    the volume of 500g sealed packet is 350 cubic centimeters. Will the packet float or sink in the water if the density of water is 1 gm per cubic meter ? What will be the mass of water displaced by this packet

    asked by ABHISHEK on January 20, 2013
  75. science

    ________ causes deep currents. a) Heavy, salty water sinking in the ocean. b) evaporation of seawater by the sun's rays c) less salty water rising to replace heavy, salty water d)all of the above d

    asked by pam on September 2, 2010
  76. Calculus

    A spherical balloon with radius 3 inches is partially filled with water. If the water in the balloon is 4 inches deep at the deepest point, how much water is released when the balloon hits the wall and breaks?

    asked by Andy on February 18, 2015
  77. Calculus

    If water is lost at 20ft^3/day when W= 10,000 ft^3 then the leakage rate constant in the differential equation is 20/10,000 or 0.002. Suppose that water flows in at F= 200,000 ft^3/day. How much water would you predict in the lake after 100 days?\ W =

    asked by Lara on February 7, 2010
  78. physics

    A fire hose a stream of water at an angle of 35degree above the horizontal. The water leaves the nozzle with a speed 25m/s. Assuming that the water behave like a projectile ,how far from a building should the fire hose be located to hit the highest

    asked by afika on May 9, 2016
  79. Chemistry

    What happens to the sample's reported water content if the salt decomposes yielding a volatile product? If the water is not completely removed from the salt during the heating process, will the reported water-to-salt mole ratio be high or low? Explain

    asked by Allison on December 6, 2010
  80. math

    A water trough is 4 m long and its cross-section is an isosceles trapezoid which is 210 cm wide at the bottom and 280 cm wide at the top, and the height is 70 cm. The trough is not full. Give an expression for V, the volume of water in the trough in cm^3,

    asked by j on October 16, 2012
  81. Differential calculus

    reservoir has the shape of a right-circular cone. The altitude is 10 feet, and the radius of the base is 4 ft. Water is poured into the reservoir at a constant rate of 5 cubic feet per minute. How fast is the water level rising when the depth of the water

    asked by Mohammed on November 26, 2016
  82. Maths

    A water tank has the shape of a rectangular prism of base 50 cm2. This tank is being filled at the rate of 12 liters per minutes. Find the rate at which the height of the water in the water tank increases; express your answer in millimeters per second. I

    asked by Elise on July 14, 2015
  83. Chemistry

    At -15.0 C, what is the maximum mass of fructose (C6H12O6) you can add to 3.00 kg of pure water and still have the solution freeze? Assume that fructose is a molecular solid and does not ionize when it dissolves in water. I'm confused on how you pick the

    asked by Tracy on February 17, 2012
  84. Maths

    A bucket holds 6 litres of water. A paddling pool is in the shape of a cuboid with dimensions 700mm x 1800mm x 3000mm. How many buckets of water would be required to fill the pool to the brim? If the pool has a leak and loses water at the rate of 20ml per

    asked by Anonymous123 on April 17, 2016
  85. chemistry

    The enthalpy change for the solution process when solid sodium hydroxide dissolves in water is -44.4 kJ/mol. When a 13.6 g sample of NaOH dissolves in 250.0 g of water in a coffee-cup calorimeter, the temperature increases from 23.0 o C to __________ o C.

    asked by Anonymous on November 15, 2010
  86. Mathematics

    At Harlan County Damn in Nebraska, the U.S. Bureau reports that the storage content of the reservoir decreased from 117,811 acre-feet (38.4 billon gallons of water) on Septmber 6, 2006 to 115,579 acre-feet (37.7 billion gallons of water) on October 6,

    asked by Kevin on September 8, 2008
  87. 7th grade math

    1. Price of the dolls: $12.99 A. Price of the dolls with a 5% sales tax. Show all of your work! [4 points] B. A discount of 20% is applied to the doll’s original price of $12.99. What is the price of the dolls with the discount applied to $12.99 + 5%

    asked by Delilah on November 27, 2012
  88. Chemistry

    Gold can be recovered from sea water by re- acting the water with zinc, which is refined from zinc oxide. 2 ZnO(s) + C(s) −→ 2 Zn(s) + CO2(g) 2 Au3+(aq) + 3 Zn(s) −→3 Zn2+(aq) + 2 Au(s) The zinc displaces the gold in the water. What mass of gold

    asked by Renee on March 17, 2014
  89. Chemistry PLS HELP!!!

    A student collects oxygen gas by water displacement at a temperature of 17 Celsius. A barometer reads 92.3 kPa. What is the pressure of the water vapor? Look it up on a water vapor pressure chart. What is the pressure of the oxygen gas? (Answer: ~14.0 mmHg

    asked by Ana on March 29, 2016
  90. Chemistry

    In a crazy scenario, the Oylan Vinegar Company has 10,000 gallons of vinegar with 0.622% concentration. This vinegar solution cannot be sold because it's too weak, but the plant manager can't bear to discard it. OVC also has a large batch of vinegar that

    asked by Mads on March 14, 2016
  91. math

    Hayden had 2 1/2 gallons of water in his watering can. The seed packet said to use 1/4 of a gallon for peppers and 5/8 of a gallon for tomatoes. Hayden then used some of the water for lettuce. If Hayden had 3/4 gallons of water left over, about how much

    asked by carla on August 25, 2016
  92. Physical Science

    The density of sea water is slightly higher than that of fresh water. The higher density is due to the fact that sea water contains salts such as sodium choride and magnesium chloride. Suppose you have a container that holds 5.00 kg of freshwater, which

    asked by Spazzo on August 24, 2010
  93. molarity

    calculate the molarity of k+ in a soln prepared by adding .2L of .200M K3PO4 and 75.0mL of .5M K3PO4. assume volumes are additive. A few of steps here and more than one way to answer the problem You need to calculate the total number of moles of K3PO4 from

    asked by Christine on April 5, 2007
  94. Biology

    When a teapot boils, we see a white cloud rising from the spout. The white cloud is composed of: A. water in the liquid phase B. water in the gaseous phase c. water molecules coming apart to from H+ and OH- ions D. H+ and OH- ions coming together to form

    asked by Anonymous on March 16, 2014
  95. Math

    My overall average right now is a 77%. A test exam of 67 has to be added in. That exam itself is only 10% added to final. Can someone help and tell me what my final will average out after 10% of the 67 will be? Thank you

    asked by Nursing student on June 25, 2015
  96. math help pls pls pls

    Water coming out from a fountain is modeled by the function f(x) = −x2 + 8x + 2 where f(x) represents the height, in feet, of the water from the fountain at different times x, in seconds. What does the average rate of change of f(x) from x = 1 to x = 4

    asked by Oscar on April 20, 2016
  97. chemistry--last time i promise

    CO(g) + H2O(g)-->CO2 + H2 (g) reaction occurs in a 2.0 Ll reactor at 800 degrees celsius. The reaction conditions are such that a complete conversion of reactants into products results. The reactor is charged initially with 5.0 atm of CO and 8.0 atm of

    asked by alexis on May 4, 2015
  98. CHEMISTRY

    brass is a subtitutional alloy consisting of a solution of copper and zinc. a particulae sample of red brass consisting of 80% copper and 20% zinc by mass has a density of 8750kg/m^3. a. what is the molality of zinc in the solid solution and B. what is the

    asked by lulu78 on October 15, 2010
  99. physics

    For a helium atom containing two protons, two neutrons and two electrons: A)Calculate the first energy levels(n=1,2,3,4,5)(answers (-54.4eV, -6.04eV, -3.4eV, -2.176eV) b)Calculate the frequency in Hz of a proton emitted from n=2 to n=1 (answer 9.86x

    asked by chanty on December 4, 2012
  100. physics university

    For a helium atom containing two protons, two neutrons and two electrons: A)Calculate the first energy levels(n=1,2,3,4,5)(answers (-54.4eV, -6.04eV, -3.4eV, -2.176eV) b)Calculate the frequency in Hz of a proton emitted from n=2 to n=1 (answer 9.86x

    asked by chanty on December 4, 2012