Questions Asked on
April 19, 2008

  1. Chemistry

    1)Ethanol is made by the fermentation of sugar. (a)Suggest a temperature for carrying out the fermentation and explain your answer. -40°C(ish), ??to do with enzymes; they can't or don't work as well in other temps./controls the speed of fermentation

    asked by Anonymous
  2. chemistry

    1)Ethanol is made by the fermentation of sugar. (a)Suggest a temperature for carrying out the fermentation and explain your answer. -40°C(ish), ??to do with enzymes; they can't or don't work as well in other temps./controls the speed of fermentation

    asked by Anonymous
  3. Physics

    An apartment has a living room whose dimensions are 2.5 m 4.8 m 5.9 m. Assume that the air in the room is composed of 79% nitrogen (N2) and 21% oxygen (O2). At a temperature of 27°C and a pressure of 1.01 105 Pa, what is the mass (in grams) of the air? g

    asked by Pierre
  4. Mechanical engineering

    A bullet of mass 50 grams is fired horizontally into a wooden block of mass 0.2kg. The wodden block is suspended from the ceiling by a long string as shown in the diagram. After impact the bullet is embedded in the block and bullet and the block swing

    asked by ibroo
  5. chemistry

    Chromium metal can be plated onto an object from an acidic solution of dichromate ions. What average current is required to plate 17.8 g of chromium metal in a time of 2.20 h?

    asked by Rishikesh
  6. physics repost

    1. A stone is dropped from rest into a well. The sound of the splash is heard exactly 1.50 s later. Find the depth of the well if the air temperature is 10.0°C. 2. Calculate the sound level in decibels of a sound wave that has an intensity of 2.25 µW/m2

    asked by chris adison
  7. Physics

    Three moles of a monatomic ideal gas expand adiabatically, and its temperature decreases from 430 to 160 K. (a) What is the work done by (or done to) the gas? Include the algebraic sign. J (b) What is the change in the internal energy of the gas? Include

    asked by Ron
  8. History

    what aspect of the compromise of 1850 was the most contentious ?

    asked by Jessica
  9. physics

    A crane in a marble quarry is mounted on the rock walls of the quarry and is supporting a 2900kg slab of marble as shown in the figure. The center of mass of the 750kg boom is located one-third of the way from the pivot end of its 15-m length, as shown.

    asked by Hong
  10. chemistry

    During the electrolysis of molten aluminum chloride in an electrolytic cell, 5.40 g of aluminum is produced at the cathode. Predict the mass of chlorine produced at the anode.

    asked by Rishikesh
  11. Chem

    Specify the number of unpaired electrons for each of the species shown below. CuCl2- (linear) Ni(NH36) 2+ NiCl4 2- (tetrahedral) CoF6 3- (weak field) Co(en)3 3+ (strong field) (en = "ethylene diamine") Would it be: 1 2 2 3 3 ??

    asked by Ginger
  12. chemistry

    What mass of Ag2CO3 would be found in 1.4 L of a saturated solution if the Ksp of Ag2CO3 is 8.2 x 10-12?

    asked by Chaitanya
  13. Radioactivity

    1) An old wooden tool is found to contain only 11.9 percent of 14C that a sample of fresh wood would. How many years old is the tool? 2) A specimen taken from the wrappings of a mummy contains 7.02 g of carbon and has an activity of 1.34 Bq. How old is the

    asked by Sandhya
  14. Chem

    Which of the following coordination compounds will most likely form a precipitate when treated with an aqueous solution of silver(I) nitrate? [Cr(NH3)3Cl3] [Cr(NH3)6]Cl3 [Cr(NH3)Cl]SO4 Na3[Cr(CN)6] Na3[CrCl6]

    asked by Ginger
  15. chemistry

    If the concentration of Pb2+ is found to be 2.3 x 10-9 mol/L in a saturated solution of Pb3(PO4)2, what is the Ksp of Pb3(PO4)2 ?

    asked by Ericka
  16. Geometry

    Find the area of a regular pentagon with radius 3cm. Round to the nearest tenth. No picture is given, but I believe a circle can surround the figure. I'm not really sure how to find the area of the figure when the side length isn't given. Can you guys help

    asked by Nikki
  17. Algebra II

    Verify that (sec theta/sin theta)(cot theta/csc theta) = csc theta is an identity. Thanks

    asked by Lucy
  18. Language art

    I'm in 5th grade. No idea about music. My teacher asked me to write papers about music, 10-15 songs, that have interesting and good vocabulary lyrics. Help please

    asked by Vinnie
  19. chemistry

    24 mL of 0.39 mol/L acetic acid is titrated with a standardized 0.33 mol/L KOH solution. Calculate the pH of the solution after 17 mL of the KOH solution has been added. Assume the Ka of acetic acid is 1.8 x 10-5.

    asked by Chaitanya
  20. Chemistry

    Calculate the equilibrium concentration of all ionic aqueous species in a solution containing 1.30 M HCl and 4.0 M C6H5OH (phenol, Ka=1.6 x 10^-10). What is the pH of the solution?

    asked by Gloria
  21. chemistry

    If the concentration of Pb2+ is found to be 2.3 x 10-9 mol/L in a saturated solution of Pb3(PO4)2, what is the Ksp of Pb3(PO4)2 ? This is my work thus far it is as far as I could get: Ksp = [Pb2+] [Pb3(PO4)2] = [2.3 x 10-9 mol/L][Pb3(PO4)2]

    asked by Anna
  22. Chem

    Why are complex ions of Zn+2 colorless?

    asked by Ginger
  23. chemistry

    A weak base with a concentration of 1.3 mol/L has a percent ionization of 0.72%. What is the Kb of this weak base?

    asked by Chaitanya,
  24. chemistry

    24 mL of 0.39 mol/L acetic acid is titrated with a standardized 0.33 mol/L KOH solution. Calculate the pH of the solution after 17 mL of the KOH solution has been added. Assume the Ka of acetic acid is 1.8 x 10-5.

    asked by Ericka
  25. Chem

    Which group shows the correct order of first ionization energy? Ca > Na > K Al > Si > P K > Ca > Ge Na > P > Cl Cs < Rb < Na I know the closer the element is to the right side of the table, group 8, the higher the ionization level, and the lower the group,

    asked by Ginger
  26. Chem

    How many liters of hydrogen gas are neede to generate 90.0g of water of 25.0°C and 1 atm pressure? What is the equation I can use to figure this?

    asked by Ginger
  27. Chem

    How many liters of hydrogen gas are needed to generate 90.0g of water 25C and 1atm pressure? What are the conversions I need?

    asked by Ginger
  28. History

    Hi, my history task for this weekend is to write an essay on this topic: "Women in World War II: An important step in the women's lieration or another opportunity for exploition" -Could you give me any insight,tips,information or starters to make this

    asked by Rachael
  29. physics repost

    Calculate the sound level in decibels of a sound wave that has an intensity of 2.25 µW/m2. F

    asked by chris adison
  30. chemistry

    What is the percent ionization of a 1.38 mol/L weak acid if its Ka = 2.7 x 10^-6? Thanks again!

    asked by Amandeep
  31. Algebra II

    State the phase shift of y=cos(theta-[pi/3]). Then graph the function. I know that you cannot graph on this site but how do I solve for the phase shift and to graph the phase shift, would I first have to graph the current equation? Thanks.

    asked by Lucy
  32. Physics

    The artificial sweetener NutraSweet is a chemical called aspartame (C14H18N2O5). (a) What is its molecular mass (in atomic mass units)? u (b) What is the mass (in kg) of an aspartame molecule? kg I know I have to get the totally mass of the aspartame, but

    asked by Ron
  33. physical

    what is body composition measured by using calipers?

    asked by eli
  34. phyiscs repost 2

    Calculate the sound level in decibels of a sound wave that has an intensity of 2.25 µW/m2 For this question don't I use B=log10(I/IO) So it would be B=log10(2.25/1.0e-12) right?

    asked by chris adison
  35. Calculus

    Will someone send me the ti 83 steps for: determine the graph of the equation: 9x^2+25y^2+z^2=225 if one is available.

    asked by Pam
  36. English Grammar

    Do you have a book? Have you a book? Have you got a book? I don't have a pen. I have not a pen. I haven't got a pen. ------------------------ Are they all grammatical?

    asked by John
  37. Physics

    A runner weighs 560 N (about 130 lb), and 74% of this weight is water. (a) How many moles of water are in the runner's body? moles (b) How many water molecules (H2O) are there? molecules

    asked by Mack
  38. English

    Who is to blame for the death of Romeo and juliet? My clues i think are, Friar, Nurse, Fate, Parents, mercuito, tybalt,prince and their haste. i need some help understanding why

    asked by joe
  39. Chem

    What is the sum of geometric and optical isomers that the complex ion Co(en)2Cl2+ exhibits? How do I begin to figure this out?

    asked by Ginger
  40. Chem

    When 0.500 g of copper(II) sulfate pentahydrate is heated at a temperature of 300°C for twenty minutes it loses some water of hydration. If the resulting sample weights 0.427 g then what is the formula of the resulting compound? What equation(s) can I use

    asked by Ginger
  41. Algebra II

    Find cos theta if sin theta = 3/5 and 90 degrees

    asked by Lucy
  42. Algebra II

    Which of the following expressions are not equal to 1? A) sin^2 theta + cot^2 theta sin^2 theta B) (sin^2 theta/1-cos theta)-cos theta C) sec^2 theta + tan^2 theta D) cot^2 theta sin^2 theta/cos^2theta Answer: D

    asked by Lucy
  43. Algebra II

    Find the exact value of cos 375 degrees. Answer: (sqrt6 + sqrt2)/4 Is this correct?

    asked by Lucy
  44. chemistry

    24 mL of 0.39 mol/L acetic acid is titrated with a standardized 0.33 mol/L KOH solution. Calculate the pH of the solution after 17 mL of the KOH solution has been added. Assume the Ka of acetic acid is 1.8 x 10-5.

    asked by Ericka
  45. trig

    y = cos(4x/3 minus 1) amplitude? Period? Two x - intercepts? y-intercept? Domain? Range? Shift along x? Shift along y? Kind of reflection?

    asked by Anna
  46. U.S. HISTORY

    What new tactic of the war was introduced by Sherman's " march to the sea " ?

    asked by Jessica
  47. Health 8th grade

    Please check this question for me thanks What method of sterilization uses the same agents as are used to disinfect instruments ? A dry heat B gas C chemical D surgial asepisis I pick C

    asked by Mersaides
  48. Health/ Basic Clinical Procedures

    please check my answer thanks An objective sign is one that A can be observed by another person B precedes a disease C is felt by the patient and can not be obsserved by another person D causes the pt the most trouble I picked A

    asked by Helana
  49. chemistry

    Calculate the value of the equilibrium constant (Kc) for the reaction shown, if SbCl5 was found to be 5.57% decomposed at 521K when its initial concentration was 7.60M. SbCl5 SbCl3 + Cl2

    asked by help!!
  50. French

    Good Afternoon, Could you please see if i have translated this english to french correctly? Most squirrels are active during the day, beginning at dawn, often resting midday, and active again until dusk. Squirrels are most active during the fall,

    asked by Rachael
  51. chemistry

    Find the temperature at which the reaction below is spontaneous given this data: Hf^o of NH3(g) = - 46 kJ/mol, S^o of NH3(g) = 192.5 J/mol·K, S^o of N2(g) = 191.5 J/mol·K, S^o of H2(g) = 130.6 J/mol·K. N2(g) + 3H2(g) 2NH3(g)

    asked by Amandeep
  52. Physics

    The artificial sweetener NutraSweet is a chemical called aspartame (C14H18N2O5). (a) What is its molecular mass (in atomic mass units)? u (b) What is the mass (in kg) of an aspartame molecule? kg

    asked by Kiante
  53. Social Studies

    What was the name of the fake government of france and who led it? Thanks so much. ^-^

    asked by Paige
  54. Math

    1)AP has U6=12.5 and U19=32 a+5d=12.5 (&) a+18d=32 (2) (2)-(1), d=1.5 therefore, a=5 (a)What is the nth term?Tn=5+(n-1)1.5 (b)What is the sum of 4 terms between U10 and U13 inclusive? 2)Un=1/2^n-3 (a)What is the nature of this sequence? (b)Calculate the

    asked by Anonymous
  55. Algebra II

    solve the equation e^2 ln x - ln (x+2) = 8/3

    asked by Lauren
  56. Chem

    If the molar mass of monatomic deuterium (D) is 2.0141 g, then what is the density of diatomic deuterium (D2) gas at 25.0°C and 1.00 atm? I know the equation for density is: d=m/v What equation(s) do I need to use to solve this?

    asked by Ginger
  57. SCI

    I need help finding info. on the following I am searching online snd not having a lot of luck on what i need. including speaker notes, that explains: • What carbohydrates are, the difference between simple and complex carbohydrates, how sugars are broken

    asked by Dawn
  58. Algebra II

    Find the exact value of: cos315 degrees. Is the answer sqrt of 2/2? Thanks

    asked by Lucy
  59. Algebra II

    Find sec theta if tan theta =1/4 and 180 degrees

    asked by Lucy
  60. Algebra II

    1) Find the exact value of cos 105 degrees by using a half-angle formula. 2)Find the solution of sin 2theta = cos theta if 0 degrees

    asked by Lucy
  61. Algebra II

    1)Find the exact value of sin 165 degrees. Answer: (sqrt6 + sqrt2)/4 2) Simplify: (4m/5n^2)- (n/2m) Answer: (8m^2-5n^3)/10n^2m Thanks

    asked by Lucy
  62. history

    i am not quite clear why the No child left behind act has been called unconstitutional. Many articles that I've read say that it is because it requires states to pay to go forth with the program. It violates the spending clause but can anyone explain

    asked by maggie r
  63. English Lit

    If you're familiar with James Baldwin please help me. I need to identify his writing style. So far I got something in between stream of consciousness and lots of poetic devices but I think I need something more concrete than that. HELP?

    asked by Dan
  64. trig

    y = sin(-3x + 3) Amplitude = Period = Two x- intercepts = y - intercept = Domain = Range = Shift along x = Shift along y = Kind of reflection =

    asked by Anna
  65. Biology

    I'm doing a report on the red panda, and I have to explain why the organism is classified in that group. The red panda's species is fulgens, but I'm not sure how to explain why its species is fulgens. Also, are there any other organisms in the Genus

    asked by Monique
  66. us history

    What gropu was largely responsible for funding the builing of the railroad system in the U.S.?

    asked by J
  67. microeconomics

    the monopolist and the perfect competitor differ in that?

    asked by Tashaml
  68. U.S. HISTORY

    whyat area in North America was point of contention between FRANCE / ENGLAND?

    asked by kilo
  69. chemistry

    24 mL of 0.39 mol/L acetic acid is titrated with a standardized 0.33 mol/L KOH solution. Calculate the pH of the solution after 17 mL of the KOH solution has been added. Assume the Ka of acetic acid is 1.8 x 10-5.

    asked by Ericka
  70. Physical science

    What is the distance from one wave to the next?

    asked by Chris
  71. U.S. HISTORY

    what philosophy blames the poor for their economic situation?

    asked by John
  72. history

    what event(s) helped lead the USA to the joining World War two ?

    asked by Sally
  73. History

    What country did cuba win its independence from at the start of the 20th century ?

    asked by Jason
  74. History

    why was the south in favor of the mexican american war ?

    asked by LuLu
  75. U.S. HISTORY

    what was the result of the jackson's indian removal act ?

    asked by Moise
  76. history

    which group did the virginia plan favor ?

    asked by Dona
  77. Health/ Basic Clinical Procedures

    please check my answer thank you True or Faise I said True Cilia prevent the entrance of pathogens into the body by providing an acidic envioroment

    asked by Helana
  78. PHYSICS

    how could an element emit alpha and beta particles and result in the same element?

    asked by cguff
  79. math

    lim x-> -infinity 1/(sqaure root of 4/x^2 plus one) i don't understan why the answer is 1.

    asked by rudy
  80. anatomy

    what's the area behind your knees called

    asked by sake
  81. Physics 12

    I've been doing alot of extra questions for physics lately, and these four are still giving me trouble. Please help me out and help me solve them, including Free Body Diagrams if possible. 1. If a curve with a radius of 60m is properly banked for a car

    asked by Joe
  82. Calculus

    Show that the rectangle with the largest area that is inscribed within a circle of radius r is a square. Find the dimensions and the area of the inscribed square. My respect goes to those who know how to tackle this one.

    asked by Evie
  83. Math

    4)Un=0.5*1.2^n Sketch this for n= (0,1,2,3,4,5) How do you sketch this?

    asked by Anonymous
  84. Algebra II

    An insect population P in a certain area fluctuates with the seasons. It is estimated that P= 17,000 + 4500sin (pi)(t)/52, where t is given in weeks. Determine the number of weeks it would take for the population to initially reach 20,000. How do I solve

    asked by Lucy
  85. Chemistry

    A tank contains 0.450 kg of oxygen(O2) compressed into a volume of 2.32 L. Estimate the gas pressure (in atm) inside the tank at 5 degrees celsius. Do I convert 0.450 kg from grams to moles, and if I do, do I use the molar mass of oxygen?

    asked by Kate
  86. marketing

    what is the decision facing Virgin Galactic

    asked by China
  87. Physics

    A runner weighs 560 N (about 130 lb), and 74% of this weight is water. (a) How many moles of water are in the runner's body? moles (b) How many water molecules (H2O) are there? molecules I dont' unstand what to do here. I know have to fine mole per h2o

    asked by James
  88. Physics

    The temperature of a monatomic ideal gas remains constant during a process in which 4500 J of heat flows out of the gas. How much work (including the proper + or - sign) is done on the gas? J

    asked by Pierre
  89. Chem

    Which of the following elements can form chemical compounds. CHECK ALL THAT APPLY. Xe Rn Kr Ne H He Is this a trick question...can't all of them form chemical compounds?

    asked by Ginger
  90. Chem

    Which of the following elements has the largest known oxidation number (in magnitude)? Pt Au Os Fe Ru

    asked by Ginger
  91. Math

    Un=0.5*1.2^n Sketch this for n= (0,1,2,3,4,5) How do you sketch this?

    asked by Anonymous
  92. Algebra II

    Find the exact value of sin(theta/2) if cos theta = 2/3 and 270 degrees

    asked by Lucy
  93. Algebra II

    Find the exact solution(s) of the system: (x^2/4)-y^2=1 and x=y^2+1 Answer:(4,sqrt3),(4,-sqrt3) 2)Write an equation for an ellipse if the endpoints of the major axis are at (-8,1) and (8,1) and the endpoints of the minor axis are at (0,-1) and (0,3).

    asked by Lucy
  94. History

    Could you please help pe formulate a thesis for the following topic; 'Women in WWII:An important step in womens libertion or another opportunity for exploition? -Thanks in advance

    asked by Alyssa Nand
  95. trig

    I am doing a similar assignment as Anaa please help! y = 3cos(x-1) Amplitude: Period: Two x - intercepts: y-intercept: Domain: Range: Shift along x: Shift along y: Kind of reflection Thank you so much!

    asked by Amandeep
  96. French

    Good Afternoon, Could you please see if i have translated this english to french correctly? Most squirrels are active during the day, beginning at dawn, often resting midday, and active again until dusk. Squirrels are most active during the fall,

    asked by Alyssa Nand
  97. chemistry

    A cell, transferred 0.146 mol of electrons with a constant current of 1.24 A. How long, in hours, did this take?

    asked by Rishikesh
  98. Physics

    An engine has an efficiency of 59% and produces 5300 J of work. Determine each of the following. (a) the input heat J (b) the rejected heat J

    asked by Kiante
  99. Math

    AP h

    asked by Anonymous
  100. chemistry

    Find the temperature at which the reaction below is spontaneous given this data: Hfo of NH3(g) = - 46 kJ/mol, So of NH3(g) = 192.5 J/mol·K, So of N2(g) = 191.5 J/mol·K, So of H2(g) = 130.6 J/mol·K. N2(g) + 3H2(g) ßà 2NH3(g)

    asked by Ericka