# Calculate the pH of the solute in an aqueous solution of 0.0047 M codeine, if the pKa of itsconjugate acid is 8.21. What is the percentage protonation of the solute?

46,915 questions, page 97
1. ## Math -

A)For a certain commodity the demand equation is given by D=-3p+20. At the price of \$1, four units of the commodity are supplied.If the supply equation is linear and the market price is \$4, find the supply equation. B) how many litres of a 70% alcohol

asked by Astro on July 3, 2015
2. ## Physics

Calculate the radius of parachute that will slow a 70 Kg person to a terminal velocity of 8 m/s. The person tries to avoid leg injury after touch down by crouching down by 60 cm then calculate the total force at the point of contact?

asked by ncphysics on June 26, 2010
3. ## science(chem)

Indicate the correct waste container for the following compounds choices are halogenated organic, nonhalogenated organic, aqueous, and organic solid a)hexane b)methylene chloride (dichloromethane) c)magnesium sulfate d)10% NaOH e)sodium hypochlorite for

asked by ~christina~ on September 2, 2007
4. ## math

a bank account earns 7% annual interest compounded continuously. you deposit \$10,000 in the account, and withdraw money continuously from the account at a rate of \$1000 per year. a. write the differential equation for the balance, B, in the account after t

asked by Anonymous on March 14, 2011
5. ## Calculus!!

Consider the differential equation given by dy/dx = xy/2. A. Let y=f(x) be the particular solution to the given differential equation with the initial condition. Based on the slope field, how does the value of f(0.2) compare to f(0)? Justify your answer.

asked by Anonymous on April 23, 2016
6. ## Math

1. –9p – 17 = 10 (1 point) –3 16 18 –16 2. w over four – 4 = 3 (1 point) –4 28 3 11 3. d over three+ 10 = 7 (1 point) 51 20 0 –9 4. –2(m – 30) = –6m (1 point) –15 –13 –8 8 5. 3n + 2= 8 + 2n (1 point) 3 4 5 6 Simplify the

asked by plz help on January 18, 2013
7. ## Chemistry

How would you start these problems? ...I suppose this is a continuation from this post: (replace the numbers with id=1395127807) But, I have yet figured out the ΔH ̊ and ΔS ̊ . But once that is figured out, how would I start problem #1? Also, for

asked by Airin on March 18, 2014
8. ## chemistry

for our lab, we are given the molarity of ClO-. We are then supposed to use beer's law to determine the molarity of the dye that was used to make the solution with. For the dye, use the first absorbance value, Ao, and calculate the initial concentration of

asked by Anonymouse one on February 21, 2011
9. ## physics

Hi! could anyone help me with this question please, I really don't know how to do this at all. Thank you so much. Question:A 330 turn solenoid with a length of 21.0 cm and a radius of 1.40 cm carries a current of 2.10 A. A second coil of four turns is

asked by Chan on March 15, 2010
10. ## chemistry

When 1.933 g of KNO3 is dissolved in 200 g of water initially at 23.57 ¢ªCelsius in a coffee-cup calorimeter, the final temperature is found to be 22.63 ¢ªCelsius. Calculate the heat released/absorbed per gram of KNO3 and per mol of KNO3 when KNO3

asked by Spenser on October 14, 2014
11. ## chemistry

When zinc metal is reacted with hydrochloric acid, zinc chloride and hydrogen gas are produced. If 16.4 ml of 2.14 M HCl are used: a) how many grams of zinc metal are needed to completely use up the acid? b) What will be the molarity of the aqueous

asked by Lindsay on December 7, 2011
12. ## Chemistry

The normal freezing point of cyclohexane is 6.55 C. When 0.458 g of benzophenone is dissolved in 15.0 g of cyclohexane, the freezing point is found to be 3.19 C. What is the experimental molar mass of benzophenone? (Kf cyclohexane = 20.0 C m^-1). A) 182 B)

asked by Ania on November 9, 2012
13. ## Algebra

I need help on these kinds of radical problems. Once I get the examples solved, I think I can do others. 1. What is the solution to the square root of -9? No solution, yes or no? 2. The square root of: 6x/3x? The answer is 2? 3. The square root of -0.01?

asked by Taurus on September 8, 2012
14. ## math

1-AND PRODUCTION sum of roots of the equation :X²-X-6=0 2-FOR what values of A the equation has no solution ax ² +3 x-7 = 0 3-For what values of x the equation has 2 solution X²-X+C=0 4-Solve the equation (X-1)²-4=0 5-Solve the equation a)2/2

asked by Anonymous on September 26, 2010
15. ## math

Decide whether each equation has one solution, no solutions, or infinitely many solutions. 1. 2(x – 3) = 2x one solution no solutions infinitely many solutions 2. 3(y – 3) = 2y – 9 + y one solution no solutions infinitely many solutions 3. 10x – 2

asked by Jman on December 3, 2012
16. ## math

Decide whether each equation has one solution, no solutions, or infinitely many solutions. 1. 2(x – 3) = 2x a.one solution b.no solutions c.infinitely many solutions 2. 3(y – 3) = 2y – 9 + y a.one solution b.no solutions c.infinitely many solutions

asked by get dunked on - sans on November 28, 2016
17. ## Chem

A scientist wants to make a solution of tribasic sodium phosphate, Na3PO4, for a laboratory experiment. How many grams of Na3PO4 will be needed to produce 650mL of a solution that has a concentration of Na+ ions of 1.50M ? Explain answer with three

asked by Yuki on September 25, 2013
18. ## Engineering Math

Assume that the number of ﬁsh P(t) after t years grows according to the logistic equation dP/dt= P(a-bP) = bP(300 − P) Find the solution of this DE (with the given initial value at t = 0) as a separable equation. Your solution formula will contain b as

asked by Erica on September 27, 2016
19. ## Chemistry

In a constant-pressure calorimeter, 65.0 mL of 0.330 M Ba(OH)2 was added to 65.0 mL of 0.660 M HCl. The reaction caused the temperature of the solution to rise from 23.85 °C to 28.35 °C. If the solution has the same density and specific heat as water,

asked by Nate on October 22, 2013
20. ## Algebra

Solve using the appropriate method. 0.05x+0.25y=66 0.15x+0.05y=72 I came up with the answer (420,180) Is this correct? a)The solution is___?(simplify your answer. Use integers or fractions for any numbers in the expression. Type an ordered pair)

asked by Josie on February 22, 2014
21. ## chemistry

We are doing a lab that requires finding the molarity of an unknown AgNO3 solution after reacting NaCl + AgNO3 --> NaNO3 and AgCl and collecting/massing the precipitate. We will be using 10.00 mL of an NaCl solution and 10.00 mL of the AgNO3 solution. We

asked by Chris on October 4, 2006
22. ## chemistry

Expressing concentration in units of μg/mL or mg/mL are common in biochemistry, where accurate molecular weights of biomolecules are not always known. The plot below is the standard curve of a Bradford assay, a colorimetric method used to determine the

asked by Libbie on September 17, 2013
23. ## Calculus

I need to find the exact solution to: 2sin2x = sqrt(x)on the interval (0,pi) This is how I started it, but I don't think it's correct. sin2x = sqrt(x)/2 2sinxcosx = sqrt(x)/2 sinxcosx = sqrt(x)/4 What do I need to do now? need to find the exact solution

asked by Jen on August 21, 2006
24. ## Chemistry

Titration was used to determine the molarity of acetic acid in vinegar. A primary standard solution of KHP was used to standardize the NaOH. 1. When performing this experiment, impure KHP was used to standardize the NaOH solution. If the impurity is

asked by Sandy on March 28, 2014
25. ## chemistry

Using the equipment below, explain how to prepare a .00052 HCL solution farom a regent bottle containing .13 HCL using only the equipment below. Note, you may make multiple solutions but you are not allowed to combine columes. for example, if you need 2

asked by Jack on June 24, 2013
26. ## chem

The solubility of KNO3 is 155 g per 100 g of water at 75 degrees celcius and 38.0 g at 25 degrees celcius. What mass (in grams) of KNO3 will crystallize out of solution if exactly 100 g of its saturated solution at 75 degrees celcius is cooled to 25

asked by Mischa on October 15, 2008
27. ## Science chemistry

Also. If you are given the conductivity of an unknown chemical, what the blue and red litmus paper change into when you check the chemical. And the pH level and solution type. How do you know the solution name and formula? I never learned how to find the

asked by Zubaida on October 29, 2016
28. ## Science chemistry

Also. If you are given the conductivity of an unknown chemical, what the blue and red litmus paper change into when you check the chemical. And the pH level and solution type. How do you know the solution name and formula? I never learned how to find the

asked by Zubaida on October 29, 2016
29. ## Chemistry

A 0.750 g sample of an unknown solid is dissolved in 100 mL of water and acidfied with 25 mL of 3 M H2SO4 then titrated with a 0.0200 M KMnO4 solution. If the unknown solid requires 12.5 mL of the KMnO4 solution to reach the endpoint, what is the % sodium

asked by Aaron on April 9, 2013
30. ## goechemistry-science

i ppted out iron(111) form a solution and weighed the ppt. then dissolved the ppt in a solution and run in an aas and get the concentration. how can i get the percentage concentration of fe3+ given that it is from fe(oh)3

asked by didymus mupambo on March 13, 2012
31. ## Chemistry

If the molality of a CaCl2 solution is .100 mol/kg, and was made from 500.0 mL of water, how many grams of CaCl2 were needed to make the solution? Step by step would be appreciated!

asked by Tim on March 14, 2013
32. ## chem

How many grams of NH4Cl must be added to 0.560 L of 1.90 M NH3 solution to yield a buffer solution with a pH of 8.50? Assume no volume change. Kb for NH3 = 1.8 10-5. i am confused as how to find the grams?

asked by hannah on March 19, 2013
33. ## College Gen. Chemistry - Science

You have 120.0 mL of a 0.245 M solution of NaCl in an open beaker. After several days, you test the solution and find that it now has a concentration of 0.348 M. How much water must have evaporated from the beaker given the new concentration?

asked by Anonymous on March 25, 2014
34. ## chemistry

A 43.20 mL sample of 0.3260 M sodium hydroxide (NaOH) is required to react completely with 36.70 mL of a phosphoric acid (H3PO4) solution. What is the molarity of the phosphoric acid solution?

asked by T on January 23, 2016
35. ## Algebra

2. The table shows the heights in inches of trees after they have been planted. What is the height of a tree that is 64 in. Tall in its pot A. 42 in B. 52 in C. 60 in D. 76 in 3. Which ordered pair is a solution to y=8x A. 0,8 B. -1,8 C. 1.5,10 D. 2,16 4.

asked by Jason on October 13, 2016
36. ## chemistry

assuming the density of a 5% acetic acid solution is 1.0 g/mL, determine the volume of the acetic acid solution necessary to neutralize 25.0mL of 0.10 M Na)H. Also record this calculation on your Report Sheet.

37. ## Chemistry

How much potassium chloride in grams is needed to prepare 1500ml solution of 3% kcl solution? This is my answer: 3x1500=4500 4500÷100=45 Answer is 45gm

asked by Anonymous on February 16, 2015
38. ## Chemistry

A solution of .12 mol/L of phosphoric acid completely neutralizes .20L of a solution of sodium hydroxide with.a concentration of .15mol/L What is the neutralizing volume of the phosphoric acid?

asked by Kelly on April 27, 2012
39. ## Chemistry

a 30 mL sample of vinegar is titrated with .1098 M NaOH. it takes 43.28 mL naOH solution to reach the endpoint. Determine the acetic acid concentration in the vinegar solution?

asked by Jeff S. on February 23, 2016
40. ## Science

A solution is prepared by dissolving 11gm glucose in 200 cm3 water at 30°c. What is the mass percentage of glucose in solution? The density of water 30°c is 0.996 glcm3?

asked by Kiran on June 8, 2018
41. ## Chemistry

In the following acid—base neutralization reaction HNO3(aq)+ KOH(aq) ----KNO3(aq) + H2O (I) What is the molarity (M) of an HNO3 solution if 50.0 ml is needed to react with 25.0 ml of 0.150M KOH solution?

asked by Tasha on October 19, 2012
42. ## Chemistry

A 200. gram sample of a salt solution contains 0.050 grams of NaCl. What is he concentration of the solution in parts per million? a)50. ppm b)250. ppm c)2.5 * 10^-4 ppm d)5.0 * 10^4 ppm

asked by Tamara on February 12, 2012
43. ## Chemestry

Approximately how many mL of 5% BaCl22H2O solution would be required to precipitate all the sulfate if we assume that your samples are pure sodium sulfate? Assume that the density of the barium chloride solution is 1.00 g/mL

asked by Peder on April 25, 2014
44. ## Chemistry

Given a solution of ammonium chloride. What additional reagent or reagents are added to prepare a buffer from the ammonium chloride solution? I know the answer is NaOH but I don't know why. Can someone explain this to me please?

asked by Ana on December 14, 2010
45. ## organic chemistry

A solution of acetic acid (CH3COOH; Ka = 1.74 x 10-5) was titrated to a final pH of 4.76 by using NaOH solution. What % of acetic acid is converted to sodium acetate (CH3COO-Na+)? Show your method

asked by brittany on September 12, 2010
46. ## AP Chemistry

A buffered solution was created by mixing solutions of NH4Cl and NH3 at 25 C. Which species, NH4+ or NH3, has the highest concentration in this buffered solution?. Justify your answer.

asked by Sara on March 26, 2015
47. ## chemistry need help

how to determine the molarity of iron (II) acetate solution? design an experiment. Would it be possible to determine the molarity be immersing a material in it then applying another substance ? confused because there is no way to know liters of solution.

asked by Anonymous on March 26, 2018
48. ## Chemistry

A solution contains 1.4 * 10^−5 mol of KBr and 0.14 mol of KCl per liter. AgNO3 is gradually added to this solution. Which forms first, solid AgBr or solid AgCl? Or do they co-precipitate?

asked by Anon on March 28, 2018
49. ## Chemistry

A 55.29-g sample of Ba(OH)2 is dissolved in enough water to make 1.20 L of solution. How many milliliters of this solution must be diluted with water in order to make 1.00 L of 0.100 M Ba(OH)2? (Ignore significant figures for this problem.)

asked by Andy on September 28, 2014
50. ## Chemistyr

A 55.29-g sample of Ba(OH)2 is dissolved in enough water to make 1.20 L of solution. How many milliliters of this solution must be diluted with water in order to make 1.00 L of 0.100 M Ba(OH)2? (Ignore significant figures for this problem.)

asked by Andy on September 28, 2014
51. ## chemistry

I was given the following problem: what is the normality of a solution containing 6 grams of H2SO4 in a 200ml solution? my teacher obtained a normality of 39normals while I took into account that I had two hydrogen free and obtained a result of 0.6 N,

asked by Paul on June 2, 2016
52. ## Chemistry

We are asked to prepare a 100 ml solution with the following 3 concentrations: 53.00 mg/ml sodium salicylate, 0.020 M FeCl3, and 0.050 M HCl. Then, we are going to take the absorbance at 520 nm. What is the best way to prepare the 100 ml solution ?

asked by Steve on April 18, 2017
53. ## Math

Solve by the elimination method. 4x +5y=1 8x +10y=2 What is the solution of the system? N Type an ordered pair. Type an integer or a fraction. Type N if there is no solution. Type I if there are infinitely many solutions.

asked by Janine on August 3, 2008
54. ## Algebra

A chemical manufacturer wishes to fill an order for 700 gallons of a 24% acid solution. Solutions of 20% and 30% are in stock. How many gallons of 20% acid solution will be used in the desired mixture?

asked by Anonymous on November 8, 2016
55. ## Chemistry

which property of a distilled water solution will not be affected by adding 50 mL of CH3OH to 100.mL of the water solution at 25? conductivity mass freezing point boiling point please help

asked by Penny on February 23, 2011
56. ## chemistry

Assuming the density of a 5% acetic acid solution is 1.0 g/mL, determine the volume of the acetic acid solution necessary to neutralize 25.0 mL of 0.10 M NaOH. Record this calculation on your report sheet.

asked by love on June 29, 2010
57. ## chemistry

1. A large salt crystal having a volume of 56 cm3 and a density of 2.17 g/cm3 was dissolved in to sufficient water to make 375 mL of solution. What is the salt concentration in the solution as g/L?

asked by Montie Stengel on May 12, 2016
58. ## chemistry

Determine the of mole of water molecules in one mole of a sample of an iron containing (nh4)2so4. FeSO4. nH2O. titrate a solution of the iron containg (solution Y)

asked by fiona on December 3, 2011
59. ## chemistry

A large salt crystal having a volume of 56 cm3 and a density of 2.17 g/cm3 was dissolved in to sufficient water to make 375 mL of solution. What is the salt concentration in the solution as g/L?

asked by chrissy on May 12, 2016
60. ## pre calculus

Create systems of equations in two variables that have (a) no solution, (b) one distinct solution, and (c) infinite solutions. Show that each system has the indicated number of solutions by using a graph or solving the system.

asked by Anonymous on November 29, 2016
61. ## Chemisty

You have 775 mL of an 0.11 M acetic acid solution. What volume (V) of 1.10 M NaOH solution must you add in order to prepare an acetate buffer of pH = 5.05? (The pKa of acetic acid is 4.76.) I don't know what to do!!! HELP!!!!

asked by Jessica on February 28, 2016
62. ## chemistry

assuming the density of a 5% acetic acid solution is 1.0g/ml, determine the volume of the acetic acid solution necessary to neutralize 25.0 ml of 0.10 m NaOH. also record this calculation on your report sheet.

asked by janvi on October 22, 2009
63. ## chemistry

Why were we instructed to add distilled water to a metal nitrate solution? What purpose does the water serve in the experiment? Just to add volume so the probe can reach the solution?

asked by Evan on October 7, 2013
64. ## biology department

Approximately how many mL of 5% BaCl22H2O solution would be required to precipitate all the sulfate if we assume that your samples are pure sodium sulfate? Assume that the density of the barium chloride solution is 1.00 g/mL

asked by negin on May 15, 2013
65. ## College Chemistry (DrBob222)

You have 120.0 mL of a 0.245 M solution of NaCl in an open beaker. After several days, you test the solution and find that it now has a concentration of 0.348 M. How much water must have evaporated from the beaker given the new concentration?

asked by Anonymous on March 25, 2014
66. ## science

A student prepared a .10M solution of acidic acid. Acidic acid has a Ka of 1.75 x 10-3. What are the hydronium ion concentration and the PH of the solution? I think the PH is 1.76 because I hit -log(1.75 x 10-3) on my calculator and that's what I got

asked by Jodi on March 21, 2007
67. ## Math Check

Hi! Can someone check these two answers? Thanks! Directions: Find the correct number of solutions for the following system of equations. 1.) 5x - 3y + 2z = 3 2x + 4y-z = 7 x - 11y + 4z = 3 2.) 2x + y- 3z = 4 4x + 2z = 10 -2x + 3y - 13z = -8 A.) One

asked by Gigi on March 6, 2015
68. ## Chemistry

What volume (mL) of a concentrated solution of sodium hydroxide (2.00 M) must be diluted to 600.0 mL to make a 0.860 M solution of sodium hydroxide? Express your answer to the nearest tenth mL.

asked by Camarra on March 10, 2010
69. ## Chemistry

You have a 12 M solution of hydrochloric acid. How many milliliters of this solution will give 25.0 mL of 2.0 M hydrochloric acid when diluted? Where to start, and Where to end. The process of figuring this problem would be greatly appreciated.

asked by George on September 4, 2008
70. ## CHM

Assuming the density of acetic acid solution is 1.0 g/mL, determine the volume of the acetic acid solution necessary to neutralize 25.0 mL of 0.10 M NaOH. Record this calculation on your report sheet

asked by JACK on January 25, 2011
71. ## Chemistry

AgNO3 solutions are often used to plate silver onto other metals. What is the maximum amount of silver in grams that can be plated out of 3.8 L of an AgNO3 solution containing 3.2% Ag by mass? (Assume that the density of the solution is 1.02 g/mL.)

asked by Kelsey G on November 30, 2010
72. ## chemistry

A flask containing 5ml of 3M hcl solution required 14.45ml of 1M NAOH for titration. How many moles of hcl are present in the solution. The density of 3M hcl is 1.05g/ml My calculation 0.005 x 3 = 0.015m 0.01445 x 1 = 0.01445m Who helps me to solve it

asked by Fai on September 2, 2012
73. ## Math 3

Solve by factoring: One of the solutions to the quadratic equation x^2 - 13x + 30 is 3. What is the other solution? Is it:(x+3) If 3 is a solution, then the quadratic contains a factor (x-3). The other factor is thus (x-10), and it follows that the other

asked by Margie on January 30, 2007
74. ## Chem

a blue solution of copper(II) sulfate is mixed with a colerless solution of sodium phosphate and a blue percipitate is formed. Using solubility rules predict the formula of the percipitate

asked by Jessica on July 6, 2011
75. ## Chemistry

determine the pH of a solution made by mixing 8 ml of 1.10M acetic acid and 2ml 0.9 M sodium acetate solution. pKa for acetic acid CH3COOH is 4.745. Can someone please explain

asked by Max on June 12, 2011
76. ## Chemistry

What volume (in mL) of a 0.300 M HNO3 solution will completely react with 43.9 mL of a 0.146 M Na2CO3 solution according to this balanced chemical equation? Na2CO3(aq)+2 HNO3(aq)->2 NaNO3(aq)+CO2(g)+H20(l)

asked by Connor Smith on November 9, 2015
77. ## Chemistry

You prepare a buffer solution by dissolving 2.00 g each of benzoic acid, C6H5COOH and sodium benzoate, NaC6H5COO in 750.0 mL of water. What is the pH of this buffer? Assume that the solution's volume is 750.0 mL.

asked by Dron on April 24, 2016
78. ## science

Is a gelatin dessert a solution, a suspension or a colloid? I think it is a suspension. Thanks you. The ingredients of gelatin are completely soluble in water and the end product is clear and transparent. It is a solution, in my opinion.

asked by Cynthia on June 10, 2007
79. ## Chemistry

(Qualitative Analysis) I know this is vague, but if i had a solution of unknown cations that appear light purple, what could be the possible list of cations in the solution? I thought Mn, Ag, Cu after doing my own tests, but i am uncertain. Just on a

asked by Kevin on November 7, 2011

Q. a 50g sample of Al(NO3)3 is dissolved in water to prepare 1500ml of solution. What is the concentration, in mol/L, of NO3 ions in the solution? -The answer is 0.47 mol/L but I don't know how to solve it.

asked by wiz on February 4, 2009
81. ## pre-calc help

Solve the given equation. (Enter your answers as a comma-separated list. Let k be any integer. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.) 5 sin^2(x)- 21 sin(x)+ 4 =0

asked by Kate on November 27, 2013
82. ## Chemistry

What volume (in mL) of a 0.300 M HNO3 solution will completely react with 43.9 mL of a 0.146 M Na2CO3 solution according to this balanced chemical equation? Na2CO3(aq)+2 HNO3(aq)->2 NaNO3(aq)+CO2(g)+H20(l)

asked by Connor Smith on November 9, 2015
83. ## Chemistry

What volume (in mL) of a 0.300 M HNO3 solution will completely react with 43.9 mL of a 0.146 M Na2CO3 solution according to this balanced chemical equation? Na2CO3(aq)+2 HNO3(aq)->2 NaNO3(aq)+CO2(g)+H20(l)

asked by Connor Smith on November 9, 2015
84. ## chemistry

2. A solution of I2 was standardized with ascorbic acid. Using a 0.1000-g sample of pure ascorbic acid, 25.32 mL of I2 were required to reach the starch end point. a) What is the molarity of the iodine solution?

asked by alexander on January 27, 2015
85. ## chemistry

suppose that after measuring the pH of 1.05 M HCl solution, three drops (0.20 mL) of the solution remained behind on the pH electrode. a) when this electrode is then dipped into 100 mL of pure distilled water, show by calculation that the pH of the water

asked by Nicollette on September 28, 2015
86. ## Biology

You have a stock solution of 100mg/100ml methylene blue and you need 6.0 ml of final solution at 2mg/100ml. Design a serial dilution using volumes between 0.1 and 10 ml. Final volume must be 6ml.

asked by Anonymous on January 19, 2015
87. ## Chemistry

Help needed on a homework problem - solution of HCN and CN- , Ka 6.2x10^-10 . Is this a buffered solution? Shouldn't the pH be greater than 7, and [OH] >[H]? Does adding a strong acid have more effect than adding a strong base? Thanks.

asked by Laura on April 25, 2010
88. ## Chemistry

What should the molar concentrations of benzoic acid and sodium benzoate be in a solution that is buffered at a pH of 4.75 and has a freezing point of -2.0 ∘C? (Assume complete dissociation of sodium benzoate and a density of 1.01 g/mL for the solution.)

asked by Albert on March 29, 2017
89. ## Chemistry

A 5.55g sample of a weak acid with Ka=1.3 x10^-4 was combined with 5.00 mL of 6.00 M NaOH and the resulting solution was diluted to 750 mL. The measured pH of the solution was 4.25. What is the molar mass of the weak acid?

asked by Trista Nigh on April 23, 2011
90. ## Math

1.) Can a system of linear equations have exactly two solutions? A. True B. False 2.) The solution of a system of equations with no solution describes what kind of lines? a.) parallel b.) perpendicular c.) skew d.) coincidental

asked by Josh on December 7, 2013
91. ## physics

A laser beam passes from air into a 25% glucose solution at an incident angle of 37 ∘ . In what direction does light travel in the glucose solution? Assume the index of refraction of air is n = 1.

asked by james on March 27, 2016
92. ## Chemistry

Determine the sulfate ion concentration in a solution prepared by diluting 15.00mL of a 0.200M aluminum sulfate solution with 35.00mL of water. Assume the volumes are additive.

asked by Carley on March 2, 2014
93. ## Attn: DrBob

A household bleach solution contains 5.25% (by mass) NaClO. How many moles of NaClO are needed to make 1000 L of the solution? (density = 1.07g/mL) This is the complete question on my assignment. It's 1000 L.

asked by Staci on March 26, 2010
94. ## Chemistry

A 23.16 ml volume of an H2A acid solution of unknown concentration with 2 drops of phenolphthalein required 14.24 ml of 0.135 M NaOH to reach the endpoint. What is the molar concentration of the acid solution?

asked by Joy on October 24, 2013
95. ## chemistry

What is the concentration of a potassium iodate solution after you complete the following porcedure? Pipette 10 mL of a 0.31 M potassium iodate stock solution to a 100-mL volumetric flask and then add water to the mark.

asked by wallace on November 6, 2018
96. ## Chemistry

How many grams of CaCl2 * 6H2O are required to make 500 milliliters of a solution having the same concentration of Cl- as one that was prepared by dissolving 75.6 grams of NaCl in enough water to make exactly 1 liter of solution?

asked by Anonymous on January 20, 2015
97. ## chemistry

75.0 mL of a 1.50 M solution is diluted to a total volume of 278 mL. A 139-mL portion of that solution is diluted by adding 139 mL of water. What is the final concentration? Assume the volumes are additive.

asked by tia on October 14, 2016
98. ## Chemistry

What should the molar concentrations of benzoic acid and sodium benzoate be in a solution that is buffered at a pH of 4.84 and has a freezing point of -2.0 ∘C? (Assume complete dissociation of sodium benzoate and a density of 1.01 g/mL for the solution.)

asked by B on April 14, 2019
99. ## Chemistry

A 6.00 M H2SO4 solution has d = 1.34 g/mL. What is the mass percent of H2SO4 in this solution? Choose one answer. a. 56.1 b. 43.9 c. 37.0 d. 58.8 When we calculated yesterday the answer was not B. 43.9....I got it wrong and don't know why if the math was

asked by CC on February 10, 2010
100. ## Chemistry

2HCr4- + 3HS03- + 5H+ -> 2Cr3+ + 3SO4^2- + 5H20. At t=0, 0.0249 mols of HCr04- are loaded in to 250ml of solution. After 1/10 of an hour, 0.00852 mol of HCrO4- remain. Assuming the solution volume remained the same, how many grams of water were formed per

asked by Tri on September 23, 2008