1. organic chemistry

    a 50% aqueous solution of ethanol (50mL total) is distilled and collected in 10-mL fractions. Predict the boiling range of each fraction

    asked by Steph on October 11, 2010
  2. Algebra/Calculus

    If x + y = xy = 3, what is x^3 + y^3? I have tried solving this using algebra alone, but my teacher told me to use complex numbers, and I don't know how to start. Can someone please guide me to the solution to this problem? Thanks Kevin

    asked by Kevin on July 11, 2016
  3. chemistry

    calculate the mass of solid NaCl that must be added to 1.5L of 0.100M AgNO3 solution to precipitate all the Ag+ ions in the form of AgCl?

    asked by NONO on November 18, 2011
  4. chemistry

    The pH of a 0.164 M aqueous solution of dimethylamine is 11.98. Write the ionization equation, calculate the values of Kb and pKa and comment on strength of the

    asked by nica on September 27, 2013
  5. Chemistry

    Equal volumes of 0.240 M AgNO3 and 0.140 M ZnCl2 solution are mixed. Calculate the quilibrium concentrations of Ag+, and Zn2+.

    asked by jina on April 8, 2011
  6. Chemistry

    A 30.00mL sample of 0.150M KOH is titrated with 0.125M HClO4 solution. Calculate the pH after the following volumes of acid have been added: 30.0 mL, 35.0 mL, 36.0 mL, 37.0 mL, 40.0 mL

    asked by Shana on November 17, 2011
  7. Maths

    Question: I graphed -2x+y=-6 Y=-(1/3)x+1 & w/ the options No Solution, Infinante Solutions, or ( , ) I found the answer is (3,1) am I correct? What would be a better way to double check my answers?

    asked by ArthurK on October 22, 2012
  8. Intro to Chemistry

    How many milliliters of 5.50 M H2SO4 must you use to prepare 500.ml of 0.2 M sulfuric acid solution? I know I need to use the formula M1V1 = M2V2 but I'm not sure how to calculate the problem?

    asked by Dawn on December 23, 2009
  9. Math

    How do i solve using the elimination method. If the system has no solution or an infinite number of solutions, state this. 2x + 10y = 58 -14x + 8y = 140

    asked by jackster on March 23, 2011
  10. CHEM 120

    What mass of ammonium nitrate must be added to 350 mL OF 0.150 M solution of ammonia to give a buffer having pH of 9.00? (Kb(NH3)= 1.8X10-5

    asked by Mxolisi on November 10, 2016
  11. chemistry

    what is the molarity of the solution which contains 5.0g of NaOH(formar weight=40g/mole)dissolved in water to make 200 ml of soluitons?

    asked by DJ on September 4, 2009
  12. physiology

    if the isotonic solution in our body reduces like near to negligible then what would be the effect will it make on hematocrit concentration will it also become low and why?? please answer fast

    asked by harry on November 30, 2011
  13. Math

    x=3-3y x+3y=-6 I'm looking for coordinates of where the two lines intercect. If you can, please show your work :) I know it's either (5,-2) or No Solution. But I hate not knowing how something works, and I know that if I don't find out, i'll regret it.

    asked by Anonymous on September 19, 2007
  14. chemistry

    What is the equation for the oxidation of beta carotene using hot concentrated potassium permanganate solution? How many ketone molecules will the product have?

    asked by sindhu on March 10, 2015
  15. chemistry

    If we dissolve 170g sodium acetate in 100g water at 100 degree centigrade , the solution will be saturated or supersaturated

    asked by jannat on November 20, 2014
  16. chemistry

    Use the law limit of Debye-Huckel and calculate the average activity coefficient for a solution of NaCl 0.050 mol/kg

    asked by william on September 9, 2017
  17. Life orientation

    (a) Why is it important to first describe the problem before you start to look for a solution (b) critically evaluate how gender and culture have an effect on assertive behavior

    asked by Plz help on August 28, 2014
  18. Intermediate Algebra

    Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this. -3x + y = 4 x + 3y = 22 Here's what I came up with (where did I go wrong) -3x + y = 4 y = 4 - 3x -3x + (4-3x) = 4 -3x + 1x =

    asked by Jordyn on October 11, 2010
  19. math

    The three co-ordinates of a rectangle are A(3,-4), B(-1,4), C(4,2).Find the fourth co-ordinate #Plz guyz may you help me out this question I tried to work with graph paper but i did not get the solution

    asked by kelvin on July 11, 2017
  20. Chemistry

    In a coffee cup calorimeter, 50.00 mL of HNO3 (aq) and 50.00 mL of KOH(aq) were mixed. The temperature of the resultant solution increased 6.5 C. What is the Delta H of this reaction?

    asked by Jaime on April 8, 2012
  21. Integral Calculus

    Find the area lenght of the portion of the curve y=2x-x^2 with 0

    asked by Akitsuke on September 15, 2008

    A 6.6 × 10–4 M solution of MnSO4 is gradually made more basic by adding NaOH. At what pH will manganese(II) hydroxide begin to precipitate? For Mn(OH)2, Ksp = 2.0 × 10–13.

    asked by Anonymous on May 3, 2010
  23. algebra

    Solve each of the following systems by using either addition or substitution. If a unique solution does not exist, state whether the system is dependent or inconsistent. 10x+2y=7 y==5x+3

    asked by Becky on December 27, 2007
  24. AP Chemistry

    Which solution has the highest pH? 1. 0.1 M C6H5NH3Cl, Kb C6H5NH2 = 4.2 × 10−10 2. 0.1 M NH2(OH)2Cl, Kb NH2OH = 6.6 × 10−9 3. 0.1 M NaCl, Kb  zero 4. 0.1 M NH4Cl, Kb NH3 = 1.8 × 10−5 5. 0.1 M CH3NH3Cl, Kb CH3NH2 = 5.0 × 10−4

    asked by Anonymous on February 25, 2014
  25. Chemistry

    Please describe how you would approximately 0.050 M standard solution of NaCl by dissolving the appropriate amount of the salt in a 250 mL volumetric flask. Thank you!

    asked by Quinn on October 1, 2012
  26. algebra

    Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this. x + 10y = 41 x + 9y = 37

    asked by Joel on February 22, 2011
  27. chemistry

    Complete and balance the displayed half reaction in neutral aqueous solution taking into account the electrons. Mg(s) → Mg2+(aq)

    asked by andy on June 1, 2010
  28. Algebra

    Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this. x + 10y = 41 x + 9y = 37

    asked by Betty on February 21, 2011
  29. algebra

    Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. -5x – 7y = 25.5 -2x + 10y = -9

    asked by Jackster on February 21, 2011
  30. Chemistry

    Calculate the mass of lithium hydroxide that must be added to 50ml of water so that it may react exactly with 5ml solution of 1.5M nitric acid.

    asked by Jeconiah on June 5, 2012
  31. Chemistry

    Calculate the pOH, pH, and percent protonation of solute in the following aqueous solution. 0.043 M quinine, given that the pKa of its conjugate acid is 8.52

    asked by Sara on May 27, 2010
  32. History

    Can someone check this? The organizational patter of the Gettysburg Address is: A. problem and solution B. Compare and contrast C. Chronological D. Order of importance***

    asked by Sam on September 12, 2016
  33. chemistry

    balance half equations in basic solution ClO3- to ClO4- Zn to zn2+ BrO3- to Br- IO3- to I2 Sn2+ to Sn4+

    asked by roxy on July 26, 2013
  34. Chemistry

    1. Balance the following half reactions in basic solution. ClO3- (aq) ¨ ClO4- (aq) Zn (s) ¨ Zn2+ (aq) BrO3- (aq) ¨ Br- (aq) IO3- (aq) ¨ I2 (s) Sn2+ ¨ Sn4+

    asked by Jenny on July 26, 2013
  35. Chemisty

    The aqueous solution of two soluble salts are mixed to precipitate an insoluble salt. Give four different equations to support this statement.

    asked by Saurav ; please help on May 3, 2015
  36. sliva

    a solution is made by dissolving 3.95g of NaCl in 78.2 mL what is the concentration of sodium chloride in units of weight/volume percent

    asked by amber on April 16, 2012
  37. chemistry

    Assuming the volumes are additive, what is the [Cl-]solution obtained by mixing 210mL of 0.600M KCl and 630ml of 0.385M MgCl2 ?

    asked by jay on September 19, 2008
  38. Chem

    If 0.03 moles of sulfuric acid is mixed with water to make 266 mililiter of solution, what is the molarity of H+? Answer in units of M.

    asked by Chandler on September 11, 2011
  39. Chemistry

    Calculate the mass of lithium hydroxide that must be added to 50ml of water so that it may react exactly with 5ml solution of 1.5M nitric acid.

    asked by Jeconiah on June 6, 2012
  40. Chemistry

    Calculate the mass of lithium hydroxide that must be added to 50ml of water so that it may react exactly with 5ml solution of 1.5M nitric acid.

    asked by Jeconiah on June 6, 2012
  41. chemistry

    Propose methods for protecting the sodium hydroxide solution in the bottle and the buret from exposure to carbon dioxide in the air.

    asked by Chris on November 3, 2014
  42. Chemistry

    How many mL of 0.0257 N KIO3 would be needed to reach the end-point in the oxidation of 34.2 mL of 0.0416N hydrazine in hydrochloric acid solution

    asked by Allen on June 4, 2017
  43. exponential equation-Algebra

    Solve the exponential equation. Express the solution set in terms of natural logarithms. 4^(x + 4) = 5^(2x + 5)-This question I don't understand.

    asked by Ang on October 26, 2007
  44. Chem 2 Lab

    Calculate the volume of a 0.150 M NaOH solution that will be required to neutralize all of the H+ ions in 0.400 grams of phosphoric acid?

    asked by Lacey on April 25, 2012
  45. Chemistry

    How many mL of the 0.1029 M standard NaOH solution is required to titrate 0.2247 g sample of KHP to the phenolphthalein end point?

    asked by Erin on October 9, 2012
  46. chemistry

    When 3.54 g of a nonelectrolyte solute is dissolved in 675 mL of water at 24 °C, the resulting solution exerts an osmotic pressure of 913 torr.

    asked by kitor on May 20, 2013
  47. CHEM 1411

    What mass of Gallium chloride is formed by the reaction of 2.6 L of a 1.44 M solution of HCl according to the following equation: 2Ga+ 6HCl= 2GaCl3+3H2

    asked by JACI WINLOW on October 18, 2016
  48. chem 1411

    what mass of H2 is produced by the reaction of 118.5 mL of a 0.8775M solution of H3PO4 according to the following equation: 2Cr+2H3PO4= 3H2+2CrPO4

    asked by JACI WINLOW on October 18, 2016
  49. science

    what wt. of hno3 is required to make 1lt. if 2N solution to be used as an oxidising agent 3cu+8HNO3=3cuno3+2NO+4H2O

    asked by anil on January 15, 2016
  50. AP Chemistry

    Calculate the pH of a 75.0 ml solution containing 0.85 M lactic acid after the addition of 0.0225 moles NaL (assume a negligible volume change.)

    asked by Davis on April 9, 2012
  51. math

    For the following problem we are asked to find an equation for the conic that satisfies the given conditions: 1. Ellipse, foci (0, -1), (8, -1), vertex (9, -1) For the solution I got: [(x – 4)^2]/25 + [(y + 1)^2]/3 = 1 Is this correct?

    asked by suri on October 29, 2007
  52. chemistry

    I need help getting this started. I made it through organic and this one stumps me, go figure :) How many grams fo NaCl are needed to make 100mL of a 0.10M solution?

    asked by AMY on January 16, 2008
  53. Chemistry

    Which of the following substances would be expected to be the strongest electrolyte (best conductor of electricity) in solution with H2O as the solvent? 1. HF 2. BaF2 3. PCl3 4. CH3OH

    asked by sara on February 23, 2014
  54. Chemistry

    Which solution will have the greatest electrical conductivity? A. 0.50MHCl B. 0.10MRbOH C. 0.50MK3PO4 D. 2.0MC6H12O6 I thought the answer would be B, but it is C. Is it not B because the Ka is too small? Otherwise, C is has the smallest Ka.

    asked by sh on May 3, 2010
  55. Chemistry

    In a titration 100 mL of 3.65 g HCl is added to 200 mL of BA(oh)2 solution of an unknown concentration until the equivalent point find molarity of ba(oh)2

    asked by Me on October 2, 2016
  56. chemistry

    How do I write a balanced equation for the following...Sulfur trioxide gas is bubbled through 125ml of a 0.165M sodium hydorxide solution?

    asked by Cindy on April 12, 2012
  57. chemistry

    Please help by Monday Explain in words how you would prepare 250.0 mL of a 3.000 M solution of Ba(OH)2 starting from solid barium hydroxide and water.

    asked by May on October 9, 2010
  58. math

    Using the following six digits, 1, 2, 4, 6, 8, and 9, fill in the blanks below to make the maximum product that you can. Use each digit only once. How does an understanding of place value help determine the best solution to this problem? __ __ __ x __ __

    asked by james on September 22, 2010
  59. chem

    Calculate the boiling point elevation of a solution containing 50.0 g of glucose dissolved in 500.0 g of water? We just started learning about this and i don't get it!

    asked by jess on May 25, 2010
  60. chemistry

    1.To make the following saline solution (375ml 0.5% w/v sodium chloride). I have weighed 1.875g of NaCl. What will be the volume of water that is required?

    asked by Christina on December 3, 2012
  61. chemistry

    How many grams of hydrogen are released by the reaction of 1.00 g of aluminum with excess potassium hydroxide solution assuming 100% yield

    asked by juan on March 12, 2015
  62. Chemistry: Freezing point depression

    What is the free sing point of a solution of ethyl alchohol, that contains 24g of the solute (C2H5OH), dissolved in 780 g of water

    asked by Matt on March 11, 2014
  63. Chemistry ( I NEED HELP REAL QUICK )

    How much Al is needed to react with 675 mL of 0.655M HCl solution according to the reaction => 2Al + 6HCl→2AlCl3+ 3H2 Help your friend!

    asked by Farrell on May 25, 2015
  64. chemistry

    what is a titration, what is the type of reaction to find the volume of hydrochloric acid needed to react with 25 of potassium hydroxide solution

    asked by bee on May 4, 2013
  65. Chemistry

    A 50 ml sample of .150M Ch3CooH is titrations with .150 M NaOh solution. Calculate the ph after the following volumes of base have been added: 49 ml, 51ml

    asked by Bob on May 27, 2015
  66. Chemistry

    a 7.50 by mass aqueous ammonia, NH3,solution has a density of 0.973 g/mol. Calculate molality and molarity? Need your ASAP please :(

    asked by Yesh on July 31, 2017
  67. Chemistry

    The addition of a non-volatile, non-electrolyte will increase the amount of your vapor found above the solution over that of the pure liquid? (True or False)

    asked by Josh on October 24, 2012
  68. Chemistry (General)

    When 280. mL of 1.50 x 10-4 M hydrochloric acid is added to 135 mL of 1.75 x 10-4 M Mg(OH)2, the resulting solution will be: acidic. basic neutral. It is impossible to tell from the information given.

    asked by Larry on October 11, 2010
  69. science

    A 68.4g sample of Potassium Chloride was added to 200g of water at 20 degrees celsius. Is the solution saturated, unsaturated, or supersaturated?

    asked by Maddy on January 3, 2012
  70. chemistry

    calculate the mass of oxalic acid dihydrate C2H2O4.2H2O required to react with 30 ml of 0.20 M sodium hydroxide solution?

    asked by lou on October 27, 2009
  71. Chemistry

    What quantity of NaOH should be dissolved in 15000l of water to obtain 4% concentration? proposed solution 4/100 * 15000 = 600

    asked by Mankah on June 30, 2016
  72. chemistry

    what is the osmotic pressure at 20 C of a solution made by dissolving 0.69 grams of sucrose C12 H22 O11 in 100 mL of water

    asked by briana on February 2, 2011
  73. chemistry

    An Erlenmeyer flask containing a hot solution is not tightly stoppered to prevent solvent loss during cooling. give reasons.

    asked by david on September 21, 2012
  74. chemistry

    assuming only glassware was supplied for the original experiment, what would be the procedural change necessary to titrate 25.00mL of commercial bleaching solution.

    asked by gladys on April 2, 2015
  75. calculus

    use euler's method with delta x=0.1 to estimate y when x=0.4 for the solution curves satisfying y(0)=1 and y(-1)=0. I made the table but i don't know what values to use or plug in.

    asked by kenneth on December 4, 2008


    asked by KELLY on September 26, 2010
  77. Pre-Calculus

    I have to use the substitution method to solve the system of equations. 4x-y=9 and 2x+3y=12 I worked this problem myself and could not find a possible solution. So I put that it is inconsistent. Is that correct? If not could you please help me?

    asked by Caroline on January 22, 2013
  78. Math

    I've been at this question almost an hour, I just need help before I start pulling hair out of my head! LOL Please Help? :D Solve the inequality and describe the solution set. y - 6 _>_ 12

    asked by Navy on June 11, 2014
  79. chemistry

    Knowing that 1 mol of a certain monoprotico acid, HX, contained in 1 litre aqueous solution, this 50% ionized, point the value of its ionization constant.

    asked by snow on August 21, 2017
  80. chemistry

    A 2 x 10^-3 M solution of MnSO4 is gradually made more basic by adding NaOH. At what pH will manganese(II) hydroxide begin to precipitate? [Ksp of Mn(OH)2=2 x 10^-13]

    asked by lauren on December 18, 2009
  81. social studies

    Identify two reasons that explain why Britain and France thought that the policy of appeasement was the best solution as a reaction to Hitler's demands.

    asked by Carly on October 27, 2008
  82. Chemistry

    Given dry, powdered Evans Blue, how would you prepare 100 mL of a 500 mg/L stock solution using water as the diluent? I would appreciate any help, even just getting started. Thanks!

    asked by Cassidy on February 10, 2014
  83. Polynomials. :) :)

    2x^4+4x^3-7x^2-x+7 Approximate the irrational solutions correct to 3 decimals. If there is more than 1 real solution, enter them from smallest to largest, separated by a comma.

    asked by Diana on May 17, 2012
  84. Algebra 2:)

    f(x)=x^5-2x^4-2x^3+4x^2-3x+3 Approximate the irrational solutions correct to 3 decimals. If there is more than 1 real solution, enter them from smallest to largest, separated by a comma.

    asked by Honey on May 17, 2012
  85. biochemistry

    calculate the mass of sodium benzoate that must be added to 1 litre of 0.4M benzoic acid with Ka=6.4 multiplied by 0.00004 solution to a buffer at pH 4.5

    asked by sammyt on September 15, 2010
  86. Chemistry

    NaOH+HNO3---> NaNO3+H2O calculate the number of moles of every ion present in solution after the reaction has occurred.

    asked by Hiba on September 14, 2010
  87. math

    solve the following system of equations algebraically or graphically for x and y: y=xsquare-6x+6 y-x=-4 For an algebraicc solution, show your work here. y=x^2-6x+6 y-x= -4 Let's substitute x-4 for y in the first equation. x-4 = x^2-6x+6 x^2 -7x + 10 = 0

    asked by Tashanna on August 12, 2007
  88. Chemistry

    Show the half equations at the anode and cathode for an electrolysis of concentrated magnesium chloride solution using inert electrode

    asked by Eddie on May 18, 2014
  89. chem

    Calculate the number of moles required to make 100 mL of a 3.0 M solution of CuSO4·5 H2O. is the answer .03? if not walk me through the steps thanks

    asked by fgf on March 16, 2015
  90. chemistry

    can you please answer this question. "The concentration of acetic acid in commercially available white vinegar is reported to be 5 % w/v. determine the molarity of the solution"

    asked by sutha on October 31, 2012

    Thank you for taking the time to respond. I am in the 5th grade. However word problems are a problem. On my homework sheet it says, Strategies Used.... Visual Thinking... My soloution First I... Then I... Next I... After that I... Finally I... My answer

    asked by To: Reiny again on November 16, 2009
  92. Science/maths

    describe how you could make the following measurements and discuss any problems you might encounter a) finding the volume of a rugby ball b) finding the diameter of tennis ball. c) findin the mass of a grain of sugar a) submerge it in water in a graduated

    asked by San on March 3, 2007
  93. Algebra 2 (check)

    I have some problems that I've answered and I need someone to check to see if I'm right. Im just posting the questons and my answer,if its wrong I'll post my work,so here it is bear with me please and thank you. 1)name which sets of numbers to which -28

    asked by erin on July 21, 2007
  94. Health care Administration

    I have to write a 700-1050 word paper that addresses the following:Develop a unique proposal that describes a new health care system. Consider the current U.S. health care system's strengths,weaknesses, and challenges. Be sure to include your answers to

    asked by Susan H. on January 10, 2010
  95. math

    can someone correct these for me. 8x –4y = 16 y = 2x –4 My answer: This problem does not have a unique solution. This problem therefore is consistent and dependent These equations are the same. If you solve the first one for y, you will see that the

    asked by jasmine20 on December 23, 2006
  96. Physics

    Let's say that the force of gravity on the equator of the Earth is 9.81 m/s^2 what is the magnitutde of gravity of something at 41.603221,-73.087749 ???? I'm guessing that 41.603221,-73.087749 is lattitude and longittude so I really have no idea what to

    asked by HELP ME! on May 19, 2009
  97. College Physics!

    Is there any way i can just get these problems set up? I just need help with the steps on how to do it. A box weighing 600 N is pushed along a horizontal floor at a constant velocity with a force of 250 N parallel to the floor. What is the coefficient of

    asked by Samantha on October 13, 2010
  98. English

    * I try to make a better world by _______________. 1. recycling used materials. 2. building some senior centers after I become wealthy. 3. inventing useful robots that can do a good job for the world. 4. becoming the President of our country. 5. making our

    asked by John on May 31, 2009
  99. Physics

    A natural gas power plant burns natural gas to produce electricity. In one second it produces 500 MJ of electrical potential energy. The power plant consumes chemical energy in order to produce electrical potential energy. --In one second does it consume

    asked by Daniel on December 9, 2015
  100. Physics

    Please help! I don't know how to solve these problems! 1 A runner dashes from the starting line (x = 0) to a point 130 m away and then turns around and runs to a point 11 m away from the starting point in 21 seconds. To the nearest tenth of a m/s what is

    asked by Yulka on September 2, 2009