Questions Asked on
December 14, 2012

  1. Chemistry

    are molar heat of vaporization and heat of vaporization the same thing?

    asked by Kendra
  2. math

    draw the shape of an ice-cream cone wrapper when it is slit from the edge to the center point and flattened out

    asked by mark
  3. French

    Hi! This is my final French paper and I would be really appreciative if someone could look it over before I turn it in. Merci! Le Mariage de ma Mère et Michael Dans ma vie, je me souviens des évènements plus que les autres, et certains sont plus

    asked by Marina
  4. Chemistry

    A solution of potassium hydroxide is in equilibrium with an undissolved solute at 45 degrees Celsius. What will happen to the mass of the potassium hydroxide if the temperature is raised to 50 degrees Celsius? (Given that heat of solution is

    asked by Dayton
  5. Chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 193.5 ppm and is initially uniform through the thickness of the

    asked by Odesa
  6. Chemistry

    (a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters. (b) Shown below are several % absorption vs. wavelength diagrams. Identify the

    asked by Odesa
  7. Chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by Odesa
  8. Chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by Odesa
  9. Chemistry

    Octane has a vapor pressure of 40 torr at 45.1 degrees Celsius and 400 torr at 104 degrees Celsius. What is its heat of vaporization? (Given R=8.314J/mol*K) Please explain.

    asked by Dayton
  10. Chemistry

    (a) Identify the feature below using correct crystallographic notation. i) (2 1 0) ii) (^-1 1/2 0) iii) (^-2 0 1) iv) (2 ^-1 0) v) [2 1 0] vi)[^-1 1/2 0] vii) [^-2 0 1] viii) [2 ^-1 0] (b) Identify the feature below using correct crystallographic notation.

    asked by Odesa
  11. Chemistry

    The glass panels of a sky roof need to be coated in order to screen out ultraviolet radiation (10-400 nm wavelength) but without color distortion in the visible spectrum. Candidate coating materials are gallium nitride (GaN) with a band gap,Eg, of 3.2 eV,

    asked by Odesa
  12. Chemistry

    The diffusion coefficient of silver (Ag) in copper (Cu) has the following values: T (K) D (m2s-1) 923 5.42 x 10-16 1173 1.34 x 10-13 (a) Calculate the activation energy for diffusion of silver in copper. Express your answer in units of J/mol. (b) You have

    asked by Odesa
  13. Chemistry

    You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can

    asked by Odesa
  14. Chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091X10^-2 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by Odesa
  15. Chemistry

    How could one lower the glass transition temperature of a germate (GeO2) glass? Select all possible ways. i)Increase the cooling rate. ii)Decrease the cooling rate. iii)Add SiO2 to the glass melt. iv)Add CaO to the glass melt.

    asked by Odesa
  16. Chemistry

    A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms?

    asked by Odesa
  17. Chemistry

    The half-life of a first order reaction is determined to be 85.5 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

    asked by Odesa
  18. Chemistry

    (a) The figure above shows how the energy of a system varies as a chemical reaction proceeds. Match the numbers features labeled on the figure above to their corresponding statements below: energy state of the reactants: 1/2/3/4/5 activation energy of the

    asked by Odesa
  19. Chemistry

    What trends the atomic radii of group 2A ?what trends the atomic radii of period 3? Why this trend occurs? Ans Atomic radii of group 2A increases . Atomic radii of period 3 decreases . I don't know how to answer the last question!! Please help me !

    asked by Maria
  20. Chemistry

    What trends the atomic radii of group 2A ?what trends the atomic radii of period 3? Why this trend occurs? Ans Atomic radii of group 2A increases . Atomic radii of period 3 decreases . I don't know how to answer the last question!! Please help me !

    asked by Maria
  21. math

    The perimeter of the office bulletin board is 24 ft. The perimeter of the sandbox is 1 1/2 times as long. What is the perimeter of the sandbox?

    asked by K
  22. Calc-extrema

    Find all relative and maximum extrema in ht efunction k(x)=(x^2-4)^-2 on the interval [-3,3].

    asked by daryl
  23. english

    sally who is sue's mother is 4 times older than sue but in 20 years sally will be older twice.how old is sally and sue

    asked by dawid
  24. maths --plse help me..

    A school has a hall which is 22 m long and 15.5 m broad . A carpet is laid inside the leaving all around a margin of 75 cm from the walls . Find the area of the carpet and the area of strip left uncovered . If the width of carpet is 82cm ,find its cost at

    asked by Anamika
  25. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 244.5 ppm and is initially uniform through the thickness of the

    asked by Anonymous
  26. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.7 kg m-3. Under these conditions the total surface area of the balloon is 0.52 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by Anonymous
  27. chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by Anonymous
  28. chemistry

    The glass panels of a sky roof need to be coated in order to screen out ultraviolet radiation (10-400 nm wavelength) but without color distortion in the visible spectrum. Candidate coating materials are gallium nitride (GaN) with a band gap,Eg, of 3.2 eV,

    asked by Anonymous
  29. chemistry

    You have two specimens of copper, both of them polycrystalline. Specimen A has an average grain size of 3.091 μm, while Specimen B has an average grain size of 7.777 μm. Which specimen will silver diffuse through more quickly? Choose the best

    asked by Anonymous
  30. maths --plse help me..

    a train leaves kanyakumari for warengel on tuesday at 10:30 a.m if warengel 1586 km from kanyakuri when will it reach there if its speed is 39 km/h.

    asked by arjun
  31. chemistry

    You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can

    asked by Anonymous
  32. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−4 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by Anonymous
  33. chemistry

    How could one lower the glass transition temperature of a germate (GeO2) glass? Select all possible ways. Increase the cooling rate. Decrease the cooling rate. Add SiO2 to the glass melt. Add CaO to the glass melt.

    asked by Anonymous
  34. chemistry

    A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms?

    asked by Anonymous
  35. chemistry

    The half-life of a first order reaction is determined to be 65.0 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

    asked by Anonymous
  36. maths

    Find the probability of drawing a diamond card in each of the consecutive draws from a well shuffled pack of cards,if the card drawn is not replaced after the first draw

    asked by Robert
  37. maths --plse help me..

    A school has a hall which is 22 m long and 15.5 m broad . A carpet is laid inside the leaving all around a margin of 75 cm from the walls . Find the area of the carpet and the area of strip left uncovered . If the width of carpet is 82cm ,find its cost at

    asked by angel
  38. Math, Algrebra II High school

    You have 29 coins, the total value of which is $1.77. The number of quarter is eight less than the number of pennies and the rest are nickels. How many of each coin do you have?

    asked by Gina
  39. Chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 379.0 ppm and is initially uniform through the thickness of the

    asked by Joel
  40. CHEMISTRY HELP PLEASE

    2NaN3(s)==>2Na(s) + 3N2(g) How many liters of N2 are produced at STP if the air bag contains 114g of NaN3 ?

    asked by Lisa
  41. chemistry

    Shown below are several % absorption vs. wavelength diagrams. Identify the correct diagram for a semiconductor.

    asked by Anonymous
  42. science

    Light is shone on a metal and photoelectrons are emitted. Can you tell me the three things from the listbelow which might cause the photoelectron emission to stop. Decreasing the intensity of the light Increasing the frequency of the light Decreasing the

    asked by centya
  43. CHEMISTRY, PLEASE HELP

    How could one lower the glass transition temperature of a germate (GeO2) glass? Select ALL possible ways. A)Increase the cooling rate. B)Decrease the cooling rate. C)Add SiO2 to the glass melt. D)Add CaO to the glass melt.

    asked by Anonymous
  44. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 165.0 ppm and is initially uniform through the thickness of the

    asked by kiril
  45. chemistry

    A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms?

    asked by kiril
  46. chemistry

    The half-life of a first order reaction is determined to be 92.0 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

    asked by kiril
  47. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−8 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by sofia
  48. chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by sofia
  49. Math 5th grade

    I am working on reducing fractions. How do I find the answer to 12 over 8?

    asked by Miya
  50. chemistry

    The diffusion coefficient of silver (Ag) in copper (Cu) has the following values: T (K) D (m2s-1) 923 5.42 x 10-16 1173 1.34 x 10-13 (a) Calculate the activation energy for diffusion of silver in copper. Express your answer in units of J/mol.

    asked by vanesa
  51. chemistry

    You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can

    asked by vanesa
  52. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 165.0 ppm and is initially uniform through the thickness of the

    asked by vanesa
  53. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by lena
  54. maths --plse help me..

    a train leaves kanyakumari for warengel on tuesday at 10:30 a.m if warengel 1586 km from kanyakuri when will it reach there if its speed is 39 km/h.

    asked by Anonymous
  55. chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by lena
  56. chemistry

    (a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

    asked by lena
  57. maths

    e=square root d/ab,make d the subject

    asked by centya
  58. equivalent

    (a+2b+3c)-(4a+6b-5c)

    asked by Anonymous
  59. public speacking

    A good resource person to go to when asking help in conducting research is a(an): A. Internet expert. B. TV reporter. C. librarian. D. insurance agent.

    asked by Buster
  60. Chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−4 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by T
  61. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 141.0 ppm and is initially uniform through the thickness of the

    asked by troubled student
  62. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.87 kg m-3. Under these conditions the total surface area of the balloon is 0.87 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by troubled student
  63. chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by troubled student
  64. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−2 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by troubled student
  65. chemistry

    How could one lower the glass transition temperature of a germate (GeO2) glass? Select all possible ways. Increase the cooling rate. Decrease the cooling rate. Add SiO2 to the glass melt. Add CaO to the glass melt.

    asked by troubled student
  66. chemistry

    A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms?

    asked by troubled student
  67. Physics

    Show or prove that tan(θ) = v2/rg

    asked by Zakari
  68. chemistry

    (a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

    asked by student
  69. Chemistry

    What is the enthalpy of formation of 2C10H22+31O2=20CO2+22H2O

    asked by Anonymous
  70. math 10 pre calculus

    12. An avalanche rescue team travels 8.55 km along a snow-covered trail. For the first section, the trail is flat. The team averages a speed of 2.7 km/h. Then, the terrain becomes mountainous and their average speed is only 1.2 km/h. The one-way trip takes

    asked by Eric
  71. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by student
  72. Stat

    Please help with this problem, not sure calculate it. Consider the standard normal distribution and find P(-1.5 < Z < 2.35).

    asked by Annie
  73. physics

    The sound intensity level at a concert increases from 85 dB to 94 dB when the concert begins. By what factor has the sound intensity increased?

    asked by amy
  74. chemistry

    The diffusion coefficient of silver (Ag) in copper (Cu) has the following values: T (K) D (m2s-1) 923 5.42 x 10-16 1173 1.34 x 10-13 (a) Calculate the activation energy for diffusion of silver in copper. Express your answer in units of J/mol.

    asked by student
  75. chemistry

    The half-life of a first order reaction is determined to be 72.5 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

    asked by ch
  76. public speacking

    When researching for supporting materials about the impact of violence in the media, it is a good idea to get assistance from this resource. A. Television B. Call-in radio C. Librarian D. Personal interview

    asked by Buster
  77. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by student
  78. physics

    A stretched string of length 80 cm has a fundamental frequency of vibration of 400 Hz. What is the speed of the sound wave in the stretched string?

    asked by amy
  79. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−6 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by lisa
  80. CHEMISTRY

    You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can

    asked by luis
  81. Math

    If52 men can do a piece of work in 35days in how many days 28 men will do it?

    asked by Anil
  82. Chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by Paul
  83. math

    The sum of a negative number and its square is 56. What is the number?

    asked by LP
  84. Algebra 2

    Suppose you invest $1600 at an annual interest rate of 7.9% compounded continuously. How much will you have in the account after 10 years? A. $35,254.34 B. $3,525.43 C. $3,435.91 D. $17,315.27

    asked by Tori
  85. Algebra 2

    Suppose you invest $1600 at an annual interest rate of 7.9% compounded continuously. How much will you have in the account after 10 years? A. $35,254.34 B. $3,525.43 C. $3,435.91 D. $17,315.27

    asked by Tori
  86. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 490.5 ppm and is initially uniform through the thickness of the

    asked by luis
  87. Chemistry

    Balance the following equation. (for a balanced eq. aA + bB → cC + dD, enter your answer as the integer abcd) MnO4−(aq) + SO32−(aq) + H+(aq) → Mn2+(aq) + SO42−(aq) + H2O(l) i got 2525 and its going in as incorrect Now you get to balance this

    asked by Trina
  88. Math, need help asap

    The ramp shown below is used to move crates of fruit to loading docks of different heights. When the horizontal distance AB is 12 meters, the height of the loading dock, BC, is 4 meters. What is the height of the loading dock DE? 12 m 8 m 9 m 15 m

    asked by Becca
  89. chemistry

    Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

    asked by kiril
  90. Jones

    In the rhombus, m

    asked by Meme
  91. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−3 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by luis
  92. intergrated math 1

    x2+7x+10

    asked by larry
  93. CHEMISTRY HELP ASAP

    Balance the following equation. (for a balanced eq. aA + bB → cC + dD, enter your answer as the integer abcd) MnO4−(aq) + SO32−(aq) + H+(aq) → Mn2+(aq) + SO42−(aq) + H2O(l) i got 2525 and its going in as incorrect Now you get to balance this

    asked by Trina
  94. Algebra 2

    The pH of a liquid is a measure of how acidic or basic it is. The concentration of hydrogen ions in a liquid is labeled [H+]. Use the formula pH = –log[H+] to find the pH level, to the nearest tenth, of a liquid with [H+] about 5.4 x 10–14. A. 14.7 B.

    asked by Tori
  95. physics

    A horizontal slingshot consists of two light, identical springs (with spring constants of 37.7 N/m) and a light cup that holds a 1.37-kg stone. Each spring has an equilibrium length of 50 cm. When the springs are in equilibrium, they line up vertically.

    asked by Anonymous
  96. Can someone please help me with balancing ASAP

    Balance the following equation. (for a balanced eq. aA + bB → cC + dD, enter your answer as the integer abcd) MnO4−(aq) + SO32−(aq) + H+(aq) → Mn2+(aq) + SO42−(aq) + H2O(l)

    asked by Trina
  97. English - Ms. Sue help

    I need help with this question i don't understand. Sometimes leaders have to make difficult decisions. Scott chose to pursue his goal of reaching the South Pole despite very dangerous weather conditions. What did he have to consider when making his

    asked by antboy
  98. Algebra 2. Please help ASAP

    The pH of a liquid is a measure of how acidic or basic it is. The concentration of hydrogen ions in a liquid is labeled [H+]. Use the formula pH = –log[H+] to find the pH level, to the nearest tenth, of a liquid with [H+] about 5.4 x 10–14. A. 14.7 B.

    asked by Tori
  99. english

    Identify what is wrong with each italicized pronoun reference. If the driver hits another car in a moving violation, the cost of your insurance will go up. indefinite pronoun ambiguous reference no specific antecedent

    asked by yamilex
  100. english

    Which sentence avoids using a pronoun reference error? Al had a dog with fleas, which he was always scratching. When I called the college, they said they were still accepting applications. When Kara went to help her sister fix supper, she was very angry.

    asked by yamilex
  101. physics

    The length of a pipe, closed at one end is is 90 cm. Calculate the frequency of the standing wave. What is the fundamental frequency of the pipe?

    asked by amy
  102. Algebra

    How do I solve 14x/5 + 7x = 23

    asked by Mae
  103. physics

    In the figure below, the scale on which the 63 kg physicist stands reads 236 N. How long will the cantaloupe take to reach the floor if the physicist drops it (from rest relative to himself) at a height of 2.1 m above the floor? How would you go about

    asked by Yes
  104. physics

    An audio speaker at a concert emits sound uniformly in all directions at a rate of 100 W. (i) Calculate the sound intensity experienced by a listener at a distance of 8 m from the speaker. The listener moves back from the speaker to protect her hearing.

    asked by amy
  105. public speacking

    When conducting research for supporting materials, it is imperative to remember: A. there is one right source for certain information. B. always to take notes and record. C. always do a personal interview. D. use only the most current source of information

    asked by Buster
  106. public speacking

    A hypothetical example is: A. a false example. B. not real but can happen. C. an example used to prove a hypothesis. D. has no place in a speech.

    asked by Buster
  107. Chemistry

    The half-life of a first order reaction is determined to be 61.0 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

    asked by yoshii
  108. CHEMISTRY

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 165.0 ppm and is initially uniform through the thickness of the

    asked by dato
  109. CHEMISTRY

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−8 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by dato
  110. English

    I trying to think of some rituals that still be practised today that be harmful, or should not be practiced. or like some that are practiced for wrong reasons. teacher gave us christmas one, and tell us that we forget the real meaning of christmas, and

    asked by Mohammad
  111. CHEMISTRY

    A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms? Update: Express your answer in Celsius.

    asked by dato
  112. CHEMISTRY

    You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can

    asked by dato
  113. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by timur
  114. math

    how do I do long division

    asked by joe
  115. physics

    The yellow line emitted by a helium discharge tube in the laboratory has a wavelength of 587 nm The same yellow line in the helium spectrum of a star has a measured wavelength of 590 nm. Calculate the speed of the moving star.

    asked by amy
  116. Spanish

    Spanish ?? Mandatos informales . Check Please, Answers are on the bottom of the page. 1) Choose the correct informal command for the following verb (Ayudar) ___________ a tu hermano A. Ayudas B. Ayudes C. Ayuda D. Ayude E. Ayudó F. Ayudaba 2) Choose the

    asked by Victoria
  117. public speacking

    When conducting research for supporting materials, it is imperative to remember: A. there is one right source for certain information. B. always to take notes and record. C. always do a personal interview. D. use only the most current source of

    asked by Buster
  118. Chemistry;Check?!

    Can you check these? Strong attractive forces that keep atoms connected together are called _____. A. valence electrons B. chemical bonds C. cations D. anions Which of the following is NOT a type of bonding that occurs between atoms? A. covalent bonding B.

    asked by Victoria
  119. Spanish, CHECK?

    Chose the correct informal command for the following verb (usar) No ______________ mi computadora. A. usas B. usaste C. usarás D. uses E. usa My answer: E

    asked by Victoria
  120. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091*10^-7 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by School girl
  121. chimistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 100.0 ppm and is initially uniform through the thickness of the

    asked by School girl
  122. chimistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.82 kg m-3. Under these conditions the total surface area of the balloon is 0.39 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by School girl
  123. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 165.0 ppm and is initially uniform through the thickness of the

    asked by student
  124. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by student
  125. chemistry

    Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−8 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free

    asked by student
  126. chemistry

    A freshman is currently enjoying the Arts Studio program she is pursuing at a well-known university. In her free time, she likes to skate, take salsa dance lessons, and cook. She particularly enjoys pickling and decides to pickle olives over a leisurely

    asked by zachary
  127. math

    The length of a rectangular garden is 4 yards more than the width. The area of the garden is 60 square yards. Find the dimensions of the garden.

    asked by LP
  128. Math

    In 10 years, 25% of a radioactive substance decays. What is its half-life? A. 25 years B. 24 years C. 20 years D. 29 years

    asked by Darwin12
  129. SraJMcGin

    Is it to personal if I ask if you have an email?! I would like you to check my spanish work before I turn it in to my teacher.

    asked by Victoria
  130. chemisty

    1.5 grams hydrogen 12 oxygen 2gram hydrogen 16 gram oxygen 2.5grams hydrogen 20grams oxygen

    asked by dionna
  131. Chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.87 kg m-3. Under these conditions the total surface area of the balloon is 0.87 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by mangozier
  132. Physical Science

    Write a paragraph or two about how and why has the atomic idea/model changed (Greeks 1600-1930)

    asked by Juliet
  133. chemistry 12

    Im doing a worksheet and i had to draw PE diagram which had the Ea(activation energy)at 80kJ and the enthalpy change is -40kJ. *All the reactants and products are gases Then it asks to describe what would happen to the diagram if the temperature dropped 25

    asked by Anonymous
  134. litercy

    what of the following is the best wat\y to get to a list of encyclopedias that are available on the web?

    asked by Anonymous
  135. Math

    Which of the following is equal to log6(t + 1) − log6(t^2 − 1)? A. log6t − log6t2 B. –log6(t − 1) C. log6t D. log6(t + 1)

    asked by Jay
  136. chemisty

    1.5 grams hydrogen 12 oxygen 2gram hydrogen 16 gram oxygen 2.5grams hydrogen 20grams oxygen

    asked by dionna
  137. English

    In which sentence is a homonym used correctly? A. I would not want to be there mother. B. He replaced the brake lining. C. Wherever you go, their you are. D. He could not break quickly enough to avoid the accident. I think the answer is "B"

    asked by Sandia
  138. Chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.79 kg m-3. Under these conditions the total surface area of the balloon is 0.47 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by anonymous
  139. algerbra

    If 1 and –6 are two of the roots of 6x^4 + 31 x^3 − 33x^2 − 16x + 12, then what are the other two? A. 2 and 3/2 B. -1 and 6 C. 1/2 and -2/3 D. -2 and 2/3

    asked by Bill
  140. math

    If you know only the outside measurements for any retangle, can you find its area? How? why does this method work?

    asked by di
  141. Chemistry

    My assignment sheet said to plot a KE distribution diagram where 10% of the molecules meet or exceed the Ea. I know the Ea and enthalpy change. But nothing else so does this mean the diagram is just a estimation of what it would look like.Or am i doing

    asked by Sky
  142. Math

    If 1 and –6 are two of the roots of 6x^4 + 31 x^3 − 33x^2 − 16x + 12, then what are the other two? A. 2 and 3/2 B. -1 and 6 C. 1/2 and -2/3 D. -2 and 2/3

    asked by Bill
  143. Math

    Find the amount of interest and the monthly payment for the loan. Purchase a car for $42,400 at 2.4% add-on rate for 5 years. (Round your answers to the nearest cent.) $_____ interest $_____ per month

    asked by Reggie
  144. Algebra 1- Math

    A software company started with 2 employees. In 6 months, the company had 14 employees. The number of employees increased at a steady rate. a. create 2 ordered pairs. b. find the slope. c. Interpret the meaning of the slope. d. Find the prediction

    asked by Tony
  145. English

    In which sentence is a homonym used correctly? A. I would not want to be there mother. B. He replaced the brake lining. C. Wherever you go, their you are. D. He could not break quickly enough to avoid the accident. I think the answer is "B"

    asked by Sandia
  146. Math

    Which of these rational numbers does the Rational Roots Theorem say can't be a solution to 14x7 + 13x5 − 19x4 + 7x2 − 6x − 21 = 0? A. 3/2 B. 2/7 C. -1 D. -(1/2)

    asked by Pat
  147. Algebra 1- Math

    At the ocean's surface the pressure is 1 atmosphere. At 66 feet below seal level, the pressure is 3 atmosphere. The Relationship between the pressure and the depth is linear. a. find the independent and dependent variable. b. create 2 ordered pairs. c.

    asked by Tony
  148. Math

    Which of the following is not a property of logarithms? A. log(A - B) = logA/logB B. logA + logB = logAB C. xloga = loga^x D. log(b) b^x = x

    asked by Pat
  149. reading anybody know?

    3. Which of the following words has a positive connotation? (1 point)childish immature babyish youthful 4. Which of the following sentences is punctuated correctly? (1 point)Is this your key, I found it near your house today? The wind blew the large,

    asked by tesj
  150. Spanish.

    PLEASE CHECK? :OO Answers On bottom: A. Chose the right verb to complete the sentence. 1. A Marta ____________ comprar un vestido nuevo. gustaría me gustaría le gustaría te gustaría 2. Yo nunca ____________ esas cosas. diría dirías deciría decirías

    asked by Victoria
  151. Math

    On which interval does the Intermediate Value Theorem guarantee that the polynomial x^4 + 7x^2 − 9x − 1 has a root? A. (-1/2,0) B. (1/2,1) C. (0,1/2) D. (-1,-1/2)

    asked by Amy
  152. Physics

    a 32 kg child stands at the edge of a circular platform that rotates at w=2rad/s about its center. Mass of platform=60kg, radius=2m. The child walks from the rim towards the center. Find the Angular speed when the child reaches a point 0.500 m from the

    asked by Help!
  153. Math

    4 x 2/3 in simplest form

    asked by Anonymous
  154. windows 7

    The __________report lists the webpage you are currently accessing and indicates if they have written cookies. A.safety B. Privacy c. protection d.liability

    asked by Tam
  155. Math

    There are 9 coins in a piggy bank in terms of dimes and nickels and the value of the dimes is 15 cents more than the value of the nickels. Find out how many of each coin there is.

    asked by Anonymous
  156. chemistry

    calculate the number of moles in this quantity: 52.5 mg ZnCl2=?

    asked by Anonymous
  157. Math

    Philip has 35 comic books. Of those comics, 2/10 take place in space. How many of Philip's comic books take place in space?

    asked by Anonymous
  158. Math

    2/7 x 3/4 simplest form

    asked by Anonymous
  159. Chemistry

    Calculate the number of moles in this quantity: 250 ml ethyl alcohol,C2H5OH(=0.789 g/ml)

    asked by Anonymous
  160. Math

    7/12 x 4/5 simplest form.

    asked by Anonymous
  161. Math

    Evaluate the expression for t • 1/8 for the given value of t. Write the answer in the simplest form. t = 4/9

    asked by Anonymous
  162. Math

    7/12 x 4/5 I cant get the answer

    asked by Anonymous
  163. Math

    If P(x) is a polynomial with P(–6) = –1.12 and P(–5) = 0.6 then which of the following must be true? A. There is a zero for P(x) between x = –6 andx = –5. B. There is a zero for P(x) between x = –1.12 and x = 0.6. C. There is a zero for P(x)

    asked by James
  164. Chemistry

    Solve the following pls. Calculate the number of grams in these quantities: 1. 0.0600 mol HC2H302 2. 4.50 x10^21 molecules glucose C6H2O6

    asked by sally
  165. science

    A fixed quantity of gas at 22°C exhibits a pressure of 739 torr and occupies a volume of 5.46 (a) Calculate the volume the gas will occupy if the pressure is increased to 1.74 atm while the temperature is held constant.

    asked by Samantha
  166. Math

    On which interval does the Intermediate Value Theorem guarantee that the polynomial x^4 + 7x^2 − 9x − 1 has a root? A. (-1/2,0) B. (1/2,1) C. (0,1/2) D. (-1,-1/2)

    asked by Anonymous
  167. Physics

    You are trying to lose weight by working out on a rowing machine. Each time you pull the rowing bar (which simulates the "oars") toward you, it moves a distance of 1.32 m in a time of 1.22 s. The readout on the display indicates that the average power you

    asked by John
  168. Math

    Write fraction in simplest form. 25x2/35x

    asked by Greg
  169. Math

    On which interval does the Intermediate Value Theorem guarantee that the polynomial x^4 + 7x^2 − 9x − 1 has a root? A. (-1/2,0) B. (1/2,1) C. (0,1/2) D. (-1,-1/2)

    asked by Anonymous
  170. Finance

    Heinz Corporation bonds carry a coupon of 8% and will mature in 5 years at $1,000. Newly issued 5-year bonds with similar characteristics are yielding 4%. Calculate today's market price of the Heinz bond. Compute your answer, submit all your work, then

    asked by dj
  171. Physics

    The drawing shows a skateboarder moving at 6.41 m/s along a horizontal section of a track that is slanted upward by 47.4 ° above the horizontal at its end, which is 0.612 m above the ground. When she leaves the track, she follows the characteristic path

    asked by John
  172. Geometry...HELP

    In rectangle KLMN, KM = 6x + 16, and LN = 49. Find the value of x.

    asked by BaileyBubble
  173. 7th grade math Ms. Sue please

    1. 2(x – 3) = 2x (1 point) one solution no solutions infinitely many solutions 2. 3(y – 3) = 2y – 9 + y (1 point) one solution no solutions infinitely many solutions 3. 10x – 2 – 6x = 3x – 2 + x (1 point) one solution no solutions infinitely

    asked by Delilah
  174. Geometry

    LM is the midsegment of trapezoid ABCD. If AB = 46 and DC = 125, what is LM?

    asked by BaileyBubble
  175. physics

    Radio waves of frequency 30 kHz are received at a location 1500 km from a transmitter. The radio reception temporarily “fades” due to destructive interference between the waves travelling parallel to the ground and the waves reflected from a layer

    asked by amy
  176. psychology

    the goal of psychodynomic therapy is to:

    asked by Nardia
  177. Biology

    A person with AB blood type is transfused with type O blood. What happens and why? ---- The textbook says there will be no immune reaction. I understand that the transfused type O red blood cells have no antigens and the recipient type AB plasma has no

    asked by Jessie
  178. lang arts

    12. The young girl was not pressured by what (other children said.) noun clause adverbial clause misplaced modifier adjectival clause

    asked by Anonymous
  179. Geometry

    Find the values of the variables and the lengths of the sides of this kite. Side A=y-4, side B=x+5,side C= x+12, side D= 2x+5

    asked by BaileyBubble
  180. Geometry

    ABCD is a rhombus. Explain why triangle ABC is congruent to triangle CDA.

    asked by BaileyBubble
  181. math

    In a right triangle, if sin ø = (5/13), what is the value of csc ø?

    asked by confused
  182. Math

    A car dealer carries out the following calculations. What is the annual percentage rate? (Round your answer to the nearest tenth.) List price $5,368.00 Options $1,625.00 Destination charges $200.00 Subtotal $7,193.00 Tax $431.58 Less trade-in $2,932.00

    asked by Reggie
  183. math

    Calculate the monthly finance charge for the following credit card transaction. Assume that it takes 10 days for a payment to be received and recorded and that the month is 30 days long. (Round your answer to the nearest cent.) $300 balance, 18% rate, $50

    asked by Reggie
  184. English - ms. sue

    ms. sue thanks for giving me list of traditions :) you read the story lottery by shirley jackson? i need help with story, i writing essay on traditions and i need to mention story parts.

    asked by Mohammad
  185. physics

    A 22 g bullet is accelerated in a rifle barrel 43.2 cm long to a speed of 907 m/s. Use the work-energy theorem to find the average force exerted on the bullet while it is being accelerated. Answer in units of N

    asked by Patrick
  186. Physics

    The force required to stretch a Hooke’s-law spring varies from 0 N to 70.4 N as we stretch the spring by moving one end 5.35 cm from its unstressed position. Find the force constant of the spring. Answer in units of N/m

    asked by Patrick
  187. Physics

    Find the work done in stretching the spring. Answer in units of J

    asked by Patrick
  188. Science

    A spring has a force constant of 50000 N/m. How far must it be stretched for its poten- tial energy to be 22 J? Answer in units of m

    asked by James
  189. Physics

    A bead slides without friction around a loop- the-loop. The bead is released from a height of 12.9 m from the bottom of the loop-the- loop which has a radius 4 m. The acceleration of gravity is 9.8 m/s2 . A 4m 12.9 m What is its speed at point A ? Answer

    asked by Richard
  190. Earth Science

    If sea level has risen by 20 cm over the past century on the coast of North America, by how much do you think it has risen over the past century on the coast of India? Explain.

    asked by kayce
  191. chemistry

    1) what mass of lead(ii) acetae is required to be dissolved in a 500.0ml volumetric so that the acetate is equal to 1.48?

    asked by Riana
  192. Earth Science

    Explain why the following statement is incorrect: Climatologists use the data from ice cores to directly measure past temperatures.

    asked by Kayce
  193. science

    how do i ansewr this question? An aerosol spray can with a volume of 400. mL contains 2.25 g of propane gas (C3H8) as a propellant (a) If the can is at 31°C, what is the pressure in the can? (b) What volume would the propane occupy at STP? (c) The can's

    asked by Samantha
  194. Finance

    In 150-300 words , What the advantages and disadvantages of consumer credit?

    asked by Shannon Stracener
  195. Physics

    A fighter jet is launched from an aircraft carrier with the aid of its own engines and a steam-powered catapult. The thrust of its engines is 3.82 x 105 N. In being launched from rest it moves through a distance of 57.2 m and has a kinetic energy of 5.71 x

    asked by Ricardo
  196. 7th grade math Ms. Sue please

    1. m – 7 < 6 (1 point) m < –1 m > 1 m < 13 m < –13 2. x + 4.5 ≥ 5.5 (1 point) x ≥ 10 x ≥ 1 x ≥ 0.1 x ≤ 1 3. p + 12 > 9 (1 point) p > 21 p > 3 p > –21 p > –3 4. Translate the following statement into an inequality: Five less than a

    asked by Delilah
  197. TO: MS SUE SCIENCE HELP

    this question has really stumped me but i have tried doing it and have came up with some possible answers: the following letters list some characteristics OF SOLIDS ACCORDING TO THE KINECTIC MOLECULAR THEORY. A.) the particles are very closely packed

    asked by SPIKE
  198. biology

    Traditional phylogenetic results have been challenged by the results of _________________

    asked by nancy
  199. biology

    Terms like punctiform and round relate to colonial ____________while smooth and curled relate to colonial___________

    asked by nancy
  200. biology

    The ___________ ____________ supplies blood from the heart to all organs except the lungs

    asked by nancy
  201. biology

    Following the usual pathway of circulation blood flows from the __________ to ___________, to_____________and to__________

    asked by nancy
  202. TO MS SUE SCIENCE HELP

    These are my last 2 questions i need help on.... 1. to determine the density of an irregularly shaped object, a student immersed the object in 21.2 ml of water in a graduated cylinder, causing the level of the water to rise to 27.8 ml. If the object had a

    asked by SPIKE
  203. chemistry

    if two solutions are prepared for the reaction.4.62g of Iron(iii)chloride in a 250ml columetric and for the sodium hydroxide,2.50g of solute in a 200ml volumetric flask is mixed.write two equations that describe the dissociatin of the ionic solids in water

    asked by Riana
  204. chemistry

    150.0ml of iron(iii)chloride solution is mixed with 180.0ml of the sodium hydroxide solution,1.65g yield of experimental iron(iii)hydroxide is obtained.find the theoretical yeild of the precipitate. how you find that ?

    asked by Riana
  205. physics

    During a baseball game, a batter hits a popup to a fielder 64 m away. The acceleration of gravity is 9.8 m/s 2 . If the ball remains in the air for 6.7 s, how high does it rise? Answer in units of m

    asked by ra
  206. physics

    Someone in a car going past you at the speed of 43 m/s drops a small rock from a height of 1.6 m. How far from the point of the drop will the rock hit the ground? The acceleration due to gravity is 9.8 m/s 2 . Answer in units of m

    asked by ra
  207. MATH! HELP!

    Sean Thomas makes $15.85 per hour. How much would he earn in a forty-hour work week?

    asked by Losa
  208. physics

    An Alaskan rescue plane traveling 37 m/s drops a package of emergency rations from a height of 149 m to a stranded party of explorers. The acceleration of gravity is 9.8 m/s 2 . Where does the package strike the ground relative to the point directly below

    asked by ra
  209. Chemistry

    The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in diameter and contains air

    asked by Savannah
  210. Math

    Sam Quaker receives a salary of $300 per week plus a 5 and 1/2% commission on his sales. Last week he sold $3,880 worth of merchandise. How much did Mr. Quaker make last week?

    asked by Rina
  211. english

    1. The Pink Palace's walls was built with pink marble. 2.The Pink Palace's walls were built with pink marble. 3.The Pink Palace's walls is built with pink marble. Which sentence is written correctly #1

    asked by Hayden
  212. English

    Which is the best way to write this sentence. Today the Pink Palace Museum has a science center too. 1.Today the Pink Palace Museum is having a science center too. 2.Today the Pink Palace Museum had a science center too. 3.Today the Pink Palace Museum will

    asked by Hayden
  213. science

    how many milliliters of 5.5M H2so4 must you use to prepare 500ml of 0.2M sulfuric acid solution? Please hurry!!!!!!

    asked by grant
  214. physics

    A 224 g particle is released from rest at point A along the diameter on the inside of a fric- tionless, hemispherical bowl of radius 44 cm. The acceleration of gravity is 9.8 m/s2 .

    asked by Richard
  215. HCR/210

    I need to find information pertaining to handling aeministrative data that a doctor does NOT need to see.

    asked by Sheila
  216. chemistry

    You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 263.5 ppm and is initially uniform through the thickness of the

    asked by kkr
  217. chemistry

    A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.86 kg m-3. Under these conditions the total surface area of the balloon is 0.56 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1.

    asked by kkr
  218. chemistry

    150.0ml of iron(iii)chloride solution is mixed with 180.0ml of the sodium hydroxide solution,1.65g yield of experimental iron(iii)hydroxide is obtained.find the theoretical yeild of the precipitate. how you find that ?

    asked by Riana