1. Chemistry

    A 5ml, 10ml, 15 ml, and 20ml Aliquot of 0.010 M sodium salicylate solution was diluted to 100 ml in four different 100ml volumetric flasks with the iron (III)Chloride solution. What are their concentrations.

    asked by Emma on November 13, 2012
  2. chemistry

    A 0.2481 g sample of marble was dissolved in 100 mL, and a 10.00 mL aliquot of the solution was titrated to an end point with 23.56 mL of 0.01052 M EDTA solution. What is the molecular weight? I know how to start this problem. Any help is appreciated!

    asked by Anonymous on October 1, 2009
  3. Chemistry

    How many millilitres of a 0.1 M solution of NaF and of 0.1 M solution of HF must be mixed to obtain 1L of buffer at pH = 4? Ka = 6.7 × 10-4 Currently I am quite confident with using the henderson and Hasselbalch equation but this question has left me

    asked by James Wilson on March 14, 2015
  4. chemistry

    A solution is made by dissolving 7.084 g of aluminum nitrate, Al(NO3)3, in 123.0 g of water. What is the mass percentage of solute in this solution? this feels like a simple problem but i just don't know. divide the two?

    asked by hershi on February 14, 2014
  5. Calculus

    1. I really don't understand what this problem is asking for The population P(t) of fish in a lake satisfies the logistic differential equation dP/dt = 3P - (P^2)/6000 If P(0) = 4000, what is ? Is the solution increasing or decreasing? && how would you

    asked by Kaylen on February 26, 2012
  6. Chemistry

    How will the addition of sodium acetate to an acetic acid solution affect the pH? A. solution becomes hotter B. It will lower the pH C. It will raise the pH D. pH will not change E. pH cannot be measured I selected answer D and got it wrong. I don't

    asked by Lisa on March 10, 2013
  7. Science

    2. Which of the following reference points would allow you to observe the speed of a car that you are traveling in? A. An airplane flying acroos the sky. B. A car traveling next to you at the same speed you are traveling. C. A car traveling next to you at

    asked by Callie on January 13, 2015
  8. Chemistry

    The densities of three solutions with known concentrations ( 20% , 50%, and 70%), and one unknown solution were determined. If the densities of 20%, 50% and 70% solutions are 0.69 and 0.58 and 0.49 g/mL, respectively, and the denisty of the unknown

    asked by Mark on February 20, 2019
  9. Chemistry

    how do I find the pH of a buffer solution given that 0.010M NH3 mixed with 0.0030M NH4Cl. Also... a 0.010M HF solution is mixed with 0.030M KF. FIND THE pH of this mixed solution.

    asked by Declan on March 25, 2012
  10. math..please i need your help

    Please can you help me to solve and get the solution for these problems. how to get the solution please help me for my homework. question: 1.Find the price of a 10% coupon bond with 10 years to maturity if interest rates: A) increase by 1% B) decrease by

    asked by jessie on September 12, 2011
  11. MS.SUE PLS HELP ME

    Please can you help me to solve and get the solution for these problems. how to get the solution please help me for my homework. question: 1.Find the price of a 10% coupon bond with 10 years to maturity if interest rates: A) increase by 1% B) decrease by

    asked by jessie on September 12, 2011
  12. chemistry

    Inglês Português Espanhol For the determination of the quantity of chloride in a physiological serum sample by the Volhard method, a sample of 25.00 ml was treated with 50.00 ml of 0.110 mol/L Silver nitrate solution and the excess of silver ions was

    asked by william on October 3, 2017
  13. chemistry Damon check my calculation

    25g of a sample of ferrous sulphate was dissolved in water containing dilute h2s04 and the volume made up to one litre. 25ml of this solution required 20ml of this solution required 20ml of n/10 kmn04 solution for complete oxidation. Calculate the

    asked by Fai on January 4, 2014
  14. statistics and probability

    Jeremy sells a magazine which is produced in order to raise money for homeless people.The probability of making a sell is independently 0.09 fr each person he approaches.Given that he approaches 40 people,find the probability that he will make; (a) Two or

    asked by masinde on December 3, 2015
  15. chemistry

    A total of 2.00mol of a compound is allowed to react with water in a foam coffee cup and the reaction produces 185g of solution. The reaction caused the temperature of the solution to rise from 21.0 to 24.7C . What is the enthalpy of this reaction? Assume

    asked by Yuli on November 25, 2011
  16. chemistry Damon helps me step by step

    1g of mixture na2c03 and k2c03 was mole made upto 250ml is aqueous solution. 25ml of this solution was neutralized. 20ml of hcl of unknown concentration. The neutralized solution required 16.24ml of 0.1N AGNo3 for precipitation, Calculate a) the % k2c03 is

    asked by Ken Hung on January 12, 2014
  17. math

    How is this different from determining if a value is a solution to an equation? If you replace the equal sign of an equation and put an inequality sign in its place, is there ever a time when the same value will be a solution to both the equation and

    asked by scooby9132002 on May 21, 2009
  18. Chemistry

    1.In a titration, 50.0 mL of an acetic acid solution required 20.0 mL of a standard solution of 0.200 mol/L NaOH(aq). The concentration of the acetic acid solution is a. 0.08 mol/L. b. 0.50 mol/L. c. 0.05 mol/L. d. 1.0 mol/L. e. 0.30 mol/L. How do I solve

    asked by Anonymous on January 16, 2018
  19. Chemistry

    An unknown salt is either NaF, NaCl or NaOCl when 0.050 moles of the salt is dissolved in water to form 0.500 L of solution, the pH of the solution is 8.08? is the solution NaF, NaCl, or NaOCl, I think its NaF?

    asked by Josh G. on November 15, 2012
  20. Chemistry

    1. Calculate the pH of a buffer solution that contains 0.32 M benzoic acid (C6H5CO2H) and 0.17 M sodium benzoate (C6H5COONa). [Ka = 6.5 × 10-5 for benzoic acid] Round your answer to two places past the decimal. 2. A solution is prepared by mixing 470 mL

    asked by Erin on April 8, 2013
  21. Chemistry

    1. Calculate the pH of a buffer solution that contains 0.32 M benzoic acid (C6H5CO2H) and 0.17 M sodium benzoate (C6H5COONa). [Ka = 6.5 × 10-5 for benzoic acid] Round your answer to two places past the decimal. 2. A solution is prepared by mixing 470 mL

    asked by Erin on April 8, 2013
  22. chemistry

    formic acid is a weak acid with a ka value of 1.8x10^-4 at 25 celsius a solution with a concentration of .424M formic acid is prepared in a laboratory. 1) Write the ionization equation for an aqeous solution of formic acid 2)determine the ph of the

    asked by zack on February 12, 2015
  23. Science -- Check my answers!

    Which of the following has the most significant impact on the environment? Natural Disasters Humans *** Ecosystems Carbon Dioxide Which step of the scientific method applies to the following scenario? Rick wants to know if rising carbon dioxide levels in

    asked by Anonymous on December 19, 2017
  24. physics

    A train is moving parallel and adjacent to a highway with a constant speed of 23 m/s. A car is traveling in the same direction as the train at 46 m/s. The car’s horn sounds at 550 Hz and the train’s whistle sounds at 360 Hz. When the car is behind the

    asked by anonumous on January 26, 2014
  25. Math

    From a window in room 7, one can observe the front door of Phillips Hall, which is about 45 yards away. A turn of the head trough an angle of 63 degrees in a counterclockwise direction enables one to see the front door to Jeremiah Smith Hall which is about

    asked by Kyle on August 15, 2010
  26. algebra

    A chemist mixes some 20% acid solution with pure 100% acid to increase the concentration. How much pure acid and acid solution should be mixed to form 100 milliliters of 40% acid solution?

    asked by jess on August 12, 2010
  27. algebra 2

    A chemist mixes some 20% acid solution with pure 100% acid to increase the concentration. How much pure acid and acid solution should be mixed to form 100 milliliters of 40% acid solution?

    asked by jenny on September 3, 2010
  28. chemistry

    Consider the following reaction CaCl2(aq) + 2Ag2SO4(aq) ! CaSO4(?) + 2AgCl(?) .Which of the following statements is true? 1. Both CaSO4 and AgCl will precipitate from solution. 2. Neither CaSO4 nor AgCl will precipitate from solution. 3. CaSO4 will

    asked by cheri on September 19, 2012
  29. Chemistry

    The concentration of a certain sodium hydroxide solution was determined by using the solution to titrate a sample of potassium hydrogen phthalate (abbreviated KHP). KHP is an acid with one acidic hydrogen and a molar mass of 204.22 g/mol. In the titration

    asked by melbell on October 7, 2014
  30. Chemistry

    You have a large amount of 8.00 M stock solution. You need 1.60 L of 3.00 M solution for an experiment. How would you prepare the desired solution without wasting any stock solution? A.) Start with 1.60 L of water. Add stock solution until you reach a

    asked by LuigiR on November 14, 2015
  31. 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 on April 19, 2008
  32. Chemistry

    An aqueous solution of copper (I) chloride is 15.7% by mass copper (I) chloride. Copper (I) is 35.8% by mass chlorine. If the solution has a density of 1.045 g/cm³, how many gallons of solution contain 2.3 kg of copper?

    asked by Matthew on October 8, 2011
  33. 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 on April 19, 2008
  34. Chemistry

    If I have to make a solution with sodium bicarbonate (baking soda) how do i find the molarity and how do i correctly make the solution??? i.e. how do i prepare a solution of sodium bicarbonate with a molarity of 0.01?

    asked by Jake on January 8, 2008
  35. chemistry

    You have been asked to do a dilution of a copper sulfate solution. The solution to be diluted is 2.88 M copper sulfate. What volume of the 2.88 M copper sulfate is required to make 250 mL of 1.03 M copper sulfate solution?

    asked by Anonymous on April 10, 2014
  36. 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 on April 19, 2008
  37. 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 on April 19, 2008
  38. chemistry

    A 0.1943g iron ore sample was dissolved in hydrochloric acid and the iron was obtained as Fe 2+ (aq). The iron solution was titrated with Ce 4+ solution according to the balanced chemical reaction shown below.After calculation, it was found that 0.0237 g

    asked by matt on October 17, 2010
  39. compound inequality

    olve. State the solution set using interval notation and graph it 1/3x > 2 and 1/4x > 2 First should I solve for x. How would you handle this problem? yes, solve for x in each.. x>6; x>8 so if the second condition is met, that is x is g reater than eight,

    asked by Telli on August 16, 2007
  40. Chemistry

    25 ml of cloudy ammonia solution is added to a 250 ml Erlenmeyer flask. 50 ml of .1 M HCl is then immediately added to the flask, which reacted with the ammonia in the solution. Next, the solution was titrated with .025 M NaOH to neutralize the excess HCl

    asked by Anonymous on February 2, 2014
  41. General Chemistry

    Starting out with 50 mL of 0.20 M NaHCO3, calculate how many mL of 0.50 M NaOH solution to add to make 100 mL of approximately 0.10 M (total) buffer solution with a pH of 10.35. By adding NaOH, some of the NaHCO3 gets converted to the conjugate Na2CO3.

    asked by Lucy on April 3, 2012
  42. General Chemistry

    A student dissolved 4.00 g of Co(NO3)2 in enough water to make 100. mL of stock solution. He took 4.00 mL of the stock solution and then diluted it with water to give 275. mL of a final solution. How many grams of NO3- ion are there in the final solution?

    asked by Dave on October 12, 2010
  43. chem

    Calculate the final concentration of a. 4.0 L of a 4.0 M HNO3 solution is added to water so that the final volume is 8.0L b. Water is added to 0.35L of a 6.0M KOH solution to make 2.0L of a diluted KOH solution. c.A 20.0 mL sample of 8.0% (m/v)NaOH is

    asked by tracy on November 8, 2012
  44. chemistry

    1. Find the molality of the solution prepared by dissolving 0.238g toluene, C7H8, in 15.8g cyclohexane 2. A pure sample of the solvent phenol has a freezing point of 40.85 degrees C. A 0.414 molal solution of isopropyl alcohol was observed to have a

    asked by kales on February 9, 2015
  45. Chemistry

    25g of a sample of ferrous sulphate was dissolved in water containing dilute h2s04 and the volume made up to one litre. 25ml of this solution required 20ml of N/10 kmn04 solution for complete oxidation. Calculate the percentage of f2s04 7h20 in the sample

    asked by Ken Hung on January 11, 2014
  46. Chem Urgent Help ?

    I have a lab dis monday .. plz someone help .. Lab Title is (( Recrystallization of a Solid )) Pre-Lab Questions.... Explain the purpose of the following in this experiment. a) using hot filtration b) not cooling (chilling) the hot filtered solution

    asked by Juliana on November 22, 2008
  47. chemistry

    1. The mass spectrum can be observed for all forms: pos. ion, neg.ion, molecules, and atoms, can't it? 2. Is there a formular to calculate how many spectrum of the substances we need to observe? Please give me some examples, and calculation. 3. I knew the

    asked by Bun on December 29, 2009
  48. Psycology

    Psychology and Health Problems Paper

    asked by Anne on March 17, 2011
  49. Algebra 1

    I forgot how to do this problems. Help? 5-|x+4| ≤ -3 ≤ is less than or equal to sign Thanks!

    asked by Skye on April 25, 2010
  50. math

    having trouble with these 2 problems & the process. -50 3/4 +(-6.05)+ 100= and 23 7/8 - 15 3/40 +(-3 4/5)= help please!!!!

    asked by Zion on October 1, 2014
  51. Science

    What are the 3 problems solved by fluid technology

    asked by Hello on May 6, 2009
  52. math

    solve the initial value problems: 1- dq/dz = 2 + sinz, q(0)=5 2-dy/dx = (x^2 -2)x, y(2)=4 3-dy/dx = 4e^5^x + x, y(0)=4 4- dy/dx 3x + 2, y(3)= 2

    asked by piper on April 19, 2010
  53. Government

    Why does Texas have so many special districts, and what are some of the problems associated with them?

    asked by Danielle on July 9, 2012
  54. algebra

    -6q^2 -40q - 50 how do you solve this i am factoring and having problems

    asked by joyce on July 23, 2010
  55. phi 103

    Logic can help analyze ethical problems.

    asked by missy on March 3, 2013
  56. Algebra help PLEASE?

    how do I work out problems such as 3w - 10w? 13w -7w -7 7w

    asked by Kurt Cornell on January 7, 2014
  57. history

    To me everyone is the same and by having someone under someone else it sure brings out a lot of problems in life

    asked by nik on May 28, 2008
  58. MULTIPLY. WRITE EACH PRODUCT IN SCIENTIFIC NOTATIO

    24.) (3 * 10^6)(2 * 10^12) 26.) (6 * 10^9) (5 * 10^4) Can you please show your work so I can get a better understanding of these problems?

    asked by InDireNeedOfHelp on June 6, 2014
  59. general

    What are some great sites to help you with chemistry problems?

    asked by Grace Peterson on October 26, 2013
  60. social studies

    what was major cause of problems with the sharecropping system

    asked by anon on February 26, 2017
  61. Algebra

    X^2=14X+5X I got Lost and on this one -2X(X+7) - (X+7) I need to factor these problems

    asked by Algebra on December 7, 2008
  62. customer service

    How do we sometimes create problems through our communication style?

    asked by mike on July 31, 2009
  63. Math

    which one of the following gives the distance between the numbers 11 and -8? -19, -3, 19, 3 How do you figure out these problems??

    asked by ana on May 12, 2018
  64. math

    how do you factor problems like (w^3)(x^2)-(10w^3)(x)+25w^3?

    asked by Dezy on February 22, 2010
  65. CIVIC EDUCATION

    WHAT ARE THE MAJOR LOCAL CIVIC PROBLEMS?

    asked by IBRAHIM UMAR on November 19, 2015
  66. math [ i need help with these.]

    2. 2x(x+3)=0 2x^2+3x=0 [i don't know what to do.] 3. y^2+8y=0 4. x^2+3x=28 5.2x^2+9x-5=0 2x^2+9x=-5 [please help me by starting off the problems, or explaining for each.]

    asked by margiee (: ! on October 24, 2008
  67. calculus

    I'm not sure where to start on these two problems, so any help is greatly appreciated. 1)4^x = x^2 2)5-x^2 = e^x

    asked by Charles on August 11, 2011
  68. us history

    What were three problems under the articles of confederation, and what were two successes?

    asked by Mysterious person on February 5, 2011
  69. 8th grade Science

    What are the 3 problems solved by fluid technology???

    asked by =) on May 6, 2009
  70. sociology

    what are the perspective of the new rights towards the society and its problems???????? can u help me please

    asked by Taskeen on February 22, 2009
  71. math

    why can subtraction problems be changed into addition?

    asked by Anonymous on September 9, 2015
  72. calculus

    how do you differentiate problems where the x and y are to the power of a fraction?

    asked by Dakota on March 21, 2011
  73. Social Studies 8R

    What were two accomplishments of reconstruction governments. What were two problems???

    asked by Laruen on September 23, 2012
  74. algebra3

    how do you work with factoring GCF problems?

    asked by Taylor on December 6, 2013
  75. Computers

    Name three problems that can arise when data becomes mixed up.

    asked by Sasha on February 17, 2013
  76. Life orientation

    Recommendations on how to address enviromental problems

    asked by Sonwabile on April 18, 2010
  77. 5th grade

    Having trouble with division word problems

    asked by Antoine on November 29, 2010
  78. Math problem

    having problems working this problem out please solve 49 5/2

    asked by Lavern on March 11, 2012
  79. Math help

    I need help on these problems. There over solving equations by factoring. 1.4x^2=8

    asked by Anonymous on March 5, 2014
  80. Math

    i am having problems solving this question can you please help? b[(12c-3a)2-10= a=2, b=3, c=4

    asked by Eli on October 7, 2008
  81. life orientation

    environmental problems impact on the community

    asked by environmental problem impacts on the community on May 7, 2013
  82. math

    what two simpler problems can you use to find 9x38

    asked by cj on November 14, 2012
  83. Math

    Could someone explain to me how to work these math problems. Thanks. -4 -n -4n + 15 -10 - (-7n) + (-9n)

    asked by Zeke on September 9, 2011
  84. College Math

    I need help solving these problems by using the substitution problem 2x-3y=16 5x+2y=21

    asked by Cam on March 20, 2013
  85. comp/155

    I am having problems writing a essay and not really sure how to start.

    asked by cheri on July 15, 2013
  86. algebra

    can some one help me with 2 problems thanks. y=1/2x+1,y=-3x+8, and y=1/2x+2, y=-x+5. show the work maybe i can figure it out some how.

    asked by dillon on January 23, 2008
  87. 9th Grade Algebra 1

    I need someone to tell me how to do these kinds of problems (In great detail please) -5x=9-2x -8x-10=4x+14

    asked by Nicole on September 13, 2010
  88. 10th grade

    How do you balance solubility equation problems?

    asked by sherita on February 15, 2010
  89. Math/Probability

    How do I calcuate probability word problems

    asked by Nikki on May 7, 2013
  90. math

    I'm having trouble simplifying two problems with exponents. Please help. Thanks. 1. [(-2)^4]^3 2. 10^7 . -1/10

    asked by Jake on April 21, 2010
  91. pre-cal: one-to-one property

    i am not sure how to do these problems... *use the one-to-one property to solve the equation for x* 1. 2^(x-2)= 1/32 2. e^(x^2-3)=e^2x

    asked by Anonymous on November 10, 2007
  92. Math

    i need help with a few problems. 1. find 3 solutions to the equation y=7x-5

    asked by Tyler on April 9, 2018
  93. Math

    What is 20x+3=5 what is x. What is 4-x=9 what is x. If you can anser these i have a lot more i`m having problems with please help.

    asked by Elizabeth on February 19, 2011
  94. Civics

    Major local civic problems

    asked by GIFT on January 16, 2019
  95. Math

    How do you solve 4-5x=3+x? I've been able to do other problems like this, but I can't get this one. The way I did it, was like 4-5x=3+x 4-4x=3 but then I get stuck? the book says it's 1/6

    asked by Lea on February 16, 2010
  96. calculus

    solve the initial value problems: 1- dq/dz = 2 + sinz, q(0)=5 2-dy/dx = (x^2 -2)x, y(2)=4 3-dy/dx = 4e^5^x + x, y(0)=4 4- dy/dx 3x + 2, y(3)= 2

    asked by piper on April 19, 2010
  97. social studies

    What were some of the problems the colonist faced in jamestown

    asked by rashawn on October 18, 2011
  98. Thanx DrBob222

    Thank you sir for helping me out with those chemistry problems.

    asked by Derrick on July 11, 2010
  99. math

    simplify the following problems. show all work 1) -1[-2(-3)^3]^2 2) -3{3-2{10-3(-2)^2}^2]^2 3) -3[4-7(-3-5)]-(-5)^2

    asked by Janae on September 27, 2011
  100. 12Chemistry

    What types of problems do pharmacists encounter?

    asked by Anonymous on March 21, 2013