# 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 289
1. ## Math

The sum of twice a number and another number is 24. The difference of twice the first number and the other number is 12. Which system would model this situation, and what is the solution?

asked by tyler on February 22, 2013
2. ## Chemistry

0.1 M solution of HCL has been diluted by a factor of 10. The Corresponding concentrations of: [OH^-] increased or decreased [H^+] increased or decreased

asked by Jon on October 9, 2011
3. ## College Chemistry

"What is the pH of a solution that is 0.50 M in sodium acetate and 0.75 M in acetic acid? (Ka for acetic acid is 1.85 x 10-5)." Would i use the Ka expression formula??

asked by James on October 19, 2010
4. ## calculus

Find the second derivative of y=loge(logex) Show that y=loge(logex) is a solution of the equation xd^2y/dx^2 + x(dy/dx)^2 + dy/dx=o

asked by daria on March 30, 2008
5. ## chemistry

A 500 mL sample of solution of H2SO4 was titrated with 60 mL of 1.5 M KOH. What was the molarity of the H2SO4 sample?

asked by Lisa Davies on October 13, 2012
6. ## Chemistry

Determinne the amount of Dextrose and NaCl in 500ml of 5% DNS. (The solution is 5% in regards to dextrose and 0.9% in regards to NACl.)

asked by Sonya on March 14, 2011
7. ## Chemistry

What is the molal concentration,m,of tin in a solution of 5.000grams of tin dissolved 95.000grams of copper

asked by Ruffles on December 4, 2013
8. ## Math

A biology class has 12 boys and 18 girls .what fraction of the class are boys? Solution. 12/30=2/5 Please tell me this correct or not.

asked by ABC on May 24, 2017
9. ## Chemistry.

If 6.02 moles of potassium react with a 0.8 M silver acetate solution, how many L of silver acetate are needed?

asked by Victoria on March 5, 2012
10. ## chem

how many 0.5 g tablets of aluminum acetate would you need in order to make 750 ml of 10% aluminum acetate solution?

asked by Harley on February 2, 2011
11. ## Chemistry.

If 6.02 moles of potassium react with a 0.8 M silver acetate solution, how many L of silver acetate are needed?

asked by Victoria on March 5, 2012
12. ## algebra

how many real number solutions does the equation have? 0=2x^2-20x+50 A. 1 solution B. 2 solutions C. no solutions** D. infinite solutions

asked by zzz on April 29, 2019
13. ## algebra

5x=7+4y 20x-16y=28 how many solutions are there for the system of equations? Infinitely many solutions No solution. two solutions or three solutions?

asked by dj on October 5, 2008
14. ## Algebra 2

6. Which of these points would be in the solution set of y < 2x – 5? The points would be in the shaded region of the graph: (2, -1) (7, 100) (100, 7) (0 , 0)

asked by Danielle on September 24, 2007
15. ## chemistry 113

How many grams of sodium sulfate do you need to create 750 mL of a 0.250 M solution of sodium sulfate

asked by ALEX GOLD on January 24, 2015
16. ## Intermediate algebra

How many quarts of water must be mixed with 8 quarts of a 25% salt solutions to obtain a 17.5% salt solution?

asked by Taylor on November 12, 2014
17. ## Algebra

If 3 is a zero of the polynomial f(x), then which of the following is NOT necessarily true? A. (x – 3) is a factor of the polynomial f(x). B. 3 is a solution of the equation f(x) = 0. C. (3, 0) is an x-intercept for f. D. (0, 3) is a y-intercept for f.

asked by Math is hard! on November 22, 2010
18. ## math-Algebra

A positive real number is 1 more than its reciprocal. Find the number: A. [1-sqrt(5)]/2 B. 2 C. [1+sqrt(5)]/2 D. No solution

asked by Anonymous on September 26, 2007
19. ## Chemistry

A) Find [Zn^2+] and [Fe(CN)6 ^4-] in saturated solution of Zn2Fe(CN)6. B) Repeat the above question in 0.1 mM ZnSO4 saturated with Zn2Fe(CN)6.

asked by jimmy on October 4, 2008
20. ## Science

49gm of sulphuric acid is present in 100ml aq. Solution .What is the molarity of sulphuric acid?

asked by Kriti on July 7, 2017
21. ## chemistry

What is the pH of the solution created by combining 12.00 mL of the 0.10 M base with 8.00 mL of the 0.10 M acid base acid NaOH HC2H3O2

asked by tia on April 9, 2008
22. ## Chemistry

How many mL of a stock solution of 2M potassium nitrate would you need to prepare 100mL of .150 M potassium nitrate?

asked by Lis on May 16, 2012
23. ## Science

what mass of sodium carbonate is present in a 3000cc of a 1.2 solution? The density of the sodium carbonate is 1.5 g/ml.

asked by Shelly Perez on September 20, 2011
24. ## Chemistry

How many moles of ethanol is contained in 250.0 ml of a 1.90M ethanol solution? A. none of these B. 7.60 C. 475 D. 0.475

asked by Lily on March 5, 2011
25. ## Chemistry

How many moles of ethanol is contained in 250.0 ml of a 1.90M ethanol solution? A. none of these B. 7.60 C. 475 D. 0.475

asked by MIchelle on March 5, 2011
26. ## Algebra

Does an inequality of the form ax > b always, sometimes, or never give a solution of the form x > c? Give examples to support your answer.

asked by Cc on September 5, 2015
27. ## chemistry

what mass of Nacl and H2o are present in 160.0g of 12 mass percentage solution of Nacl?

asked by nketo w on February 25, 2011
28. ## chemistry

How much ml of H2So4 added to make 0.02M H2So4 solution to make volume 250ml?

asked by unknown on April 17, 2010
29. ## chemistry

What is the [CH3NH3+] of a solution which is 0.1003 M in CH3NH2 and 0.1204 M in CsOH? CH3NH2(aq) + H2O(l) « CH3NH3+(aq) + OH−(aq)

asked by Andy on May 6, 2014
30. ## math

Solve this equation. Verify your solution using a graphing utility. log_a(x - 1) - log_a(x + 6) = log_a(x - 2) - log_a(x + 3)

asked by Kristina on October 25, 2008
31. ## chemistry

A 30.0 mL sample of phosphoric acid is titrated with 18.0 mL of 3.0 M NaOH solution. What is the molarity of the phosphoric acid?

asked by confused on December 7, 2011
32. ## s

, what would be the pH of a solution of 0.1 M acetic acid and 1 M sodium acetate if the pKa for acetic acid is assumed to be 4.74?

asked by Anonymous on January 23, 2016
33. ## Elementary manth

Jose said that the square root -X=3 has no solutino since the square root is a negative, is this true. I think it does has a solution

asked by Molly on November 5, 2014
34. ## Algebra

I can find no solution to this system of equations. Solve the system of equations using the substitution method 2x + 4y = -2 2x - y = 4

asked by slomo on January 7, 2015
35. ## Math

How many real-number solutions does the equation have? –7x2 + 6x + 3 = 0 one solution two solutions*********** no solutions infinitely many solutions

asked by Mike on May 11, 2016
36. ## Algebra 2

Find the A) Constant of Variation, B) the Equation of the Variation, and the C) the Solution Y varies directly with x. If y = -4 when x = 2, find y when x = 6.

asked by Nate on February 15, 2018
37. ## chemistry

The concentration of ammonium phosphate, (NH4)3PO4, is 1.60 M. What is the concentration of ammonium ions in solution?

asked by Anonymous on December 11, 2012
38. ## math

if y=y(x) is a solution of y' = y/x + x/y and y(1)=2 then y(e) is ? so I used the homogeneous equation method and subbed v=y/x then found y' = xv' +v and subbed those into the original equation to get xv' + v = v +1/v what do i do from here?

asked by Anonymous on August 1, 2015
39. ## Chemistry

How many moles of calcium carbonate, CaCO3, are in 1.500 L of a 0.40M calcium carbonate solution?

asked by Karina on August 25, 2017
40. ## Chemistry-confused

What is the molarity of a 15%(w/v) solution of nickel (III) ferrocyanide? I can't figure out what nickel(III) ferrocynade is?

asked by Beth on November 30, 2010
41. ## Chemistry

What is the difference between Citric Acid C6H8O7 and H3C6H5O7? I am seeing both and don't know which is the right one. Is one a solution of citric acid? Thanks

asked by Matthew on September 29, 2014
42. ## Chemistry

If you have 324 grams KBr and want to produce a 1.48 M solution in water how many grams of water are needed?

asked by Angela on April 6, 2015
43. ## Chemistry

What is the pH of the solution created by combining 12.40 mL of the 0.10 M NaOH(aq) with 8.00 mL of the 0.10 M HCl(aq)? with 8.00 mL of the 0.10 M HC2H3O2(aq)? I know how to solve for HCl but not with HC2H3O2.

asked by Manali on May 1, 2010
44. ## chemistry

Tell how you would prepare an acetic acid/acetate buffer solution having apH of 3.79. Ka for acetic acid = 1.85 x 10-5

asked by jenn on December 1, 2016
45. ## chemistry

25 milliliters of tartaric acid solution is titrated against 31 milliliters of NH4OH. What is the normality of the NH4OH?

asked by Stephen on October 3, 2012
46. ## Chemistry ....help

If NaNO3 is cooled from 70C to 10C ; how much solid NaNO3 will come out of solution as a solid salt? Help me !!!

asked by Maria on March 18, 2013
47. ## chem

Write a total ionic equation for the reaction (if any) of FeCl2 with Cu, and for the reaction (if any) of FeCl2 solution with Al

asked by Stef on October 16, 2011
48. ## Chemistry

How many moles of ethanol is contained in 250.0 ml of a 1.90M ethanol solution? A. none of these B. 7.60 C. 475 D. 0.475

asked by Philip on March 5, 2011
49. ## chemistry

3. You will be using 10.0 mL of silver nitrate solution labeled 170.0 g/L. How many grams of silver nitrate will be in your 10.0 mL sample?

asked by Anonymous on March 12, 2013
50. ## Math Help PLease Fast!!!!!!!!!!!!!!

Graph the system of inequalities. Then use your graph to identify the point that represents a solution to the system. x > ¨C2 y ¡Ü 2x + 7 A. (¨C1, 6) B. (1, 11) C. (¨C1, 4) D. (¨C3, ¨C1)

asked by Lola on December 12, 2012
51. ## chemistry

You need to make a 300 ml of a .37M Na2 SO4 solution. How much Na2 So4 should you weigh out?

asked by mika on July 3, 2016
52. ## Chemistry

How many grams of a 17.7% potassium sulfate solution would contain 419.9 g potassium sulfate? Answer in units of g

asked by Kristen on March 13, 2014
53. ## chemistry

Use the initial pH of the acetic acid solution to find the initial [H3O+] and initial [CH3COO-]. I have an initial pH of 2.2 Thanks

asked by Sarah on April 6, 2008
54. ## chem

Can you please tell me if these are right? Determine the pH for the following solutions A [OH-] = 1.0 X 10^-7 M I got 7 B. [H3O+ = 4.2 X 10 ^-3M I got 2.4 C. [H3O+]= 0.0001M I got 4 D. [OH-] = 8.5 X10^-9M I got 5.9 What are the [H3O+] and [OH-] for a

asked by Jessie on December 6, 2010
55. ## Math

How many milligrams of sodium chloride are in 250 ml of 0.9% sodium chloride solution (w/v)? I got 2,270 grams.

asked by Natasha on October 28, 2018
56. ## Math

A system of equations is shown below: x + y = 3 2x − y = 6 The x-coordinate of the solution to this system of equations is _____. I'm thinking it could be X=3

asked by Student on December 11, 2015
57. ## Chemistry

What volume of each solution contains 0.220mol of NaI? a.) 0.142M NaI b.) 0.902M NaI c.) 1.61M NaI

asked by M on May 1, 2014
58. ## chemistry

how do i figure out the dilutions of 1.5L of a 15.0% (v/v) NaCl/water solution, what would the concentration of NaCl be if you added 3.0L of water

asked by sara on April 15, 2016
59. ## physics

a ball of mass 0.1kg is thrown vertically upwards with an initial velocity of 80m/s.calculate the potential energy (I) half way up (ii) at its maximum height.what is the kinetic energy as it leaves the ground

asked by stephen on March 13, 2016
60. ## statistics

Calculate the Pearson’s correlation coefficient Assessed value (R’000) Selling price (R’000) 116 185 160 246 144 236 103 162 205 300

asked by shahistha on September 15, 2014
61. ## Mechanics

A soccer player kicked a ball at an angle of 37 to the horizontal if the range covered by the ball is 240.3m calculate What is the initial velocity of projection? The time of flight? The maximum leight attained

asked by Ikpa olaguaziba on March 31, 2019
62. ## chemistry

I got C_4 H_3 O_8 for this question but I'd like someone to check my answer, please. A 1.012 g sample of a compound containing C, H, and O was burned to produce 2.145 g CO2 and 0.3293 g H2O. Calculate the empirical formula of the compound

asked by mark on January 21, 2012
63. ## physics

A 2kg and a 4kg hang freely at opposite ends of a light inextensible string which passes over a small and light pulley fixed to a rigid support calculate the acceleration of the system

asked by john on January 11, 2013
64. ## chemistry

when we make CH3MgX first we take Mg in baloon.then we active it with I2 and finally we increase CH3Cl. we know product is very sensitive in air then we carry a mount of it with syring. Now how can we calculate molarity of product becouse we donot know

asked by shahram on April 10, 2011
65. ## computer science

The problem is to calculate the usable area in square feet of a house. Assume that the house has a maximum of four rooms, and that each room is rectangular. I need help writing a program description,analysis,test,and with pseuocode with it.

asked by Michelle on September 12, 2014
66. ## Chemistry

Calculate ΔH∘f (in kilojoules per mole) for benzene, C6H6, from the following data: 2C6H6(l)+15O2(g)→12CO2(g)+6H2O(l) ΔH∘ = -6534kJ ΔH∘f (CO2) = -393.5kJ/mol ΔH∘f (H2O) = - 285.8kJ/mol

asked by Tyler on April 20, 2014
67. ## Chemistry

For the reaction 1 CaCO3(s) + 2 HCl(aq) 1 CaCl2(aq) + 1 H2O(l) + 1 CO2(g) Calculate K, the equilibrium constant, from thermodynamic data at 293 K. (Hint #1: Assume that S and H do not change with temperature.) (Hint #2: Work in J/mol)

asked by Faith on December 14, 2011
68. ## FOR NABIAH

You now have 6 different posts going for the same "cake question" I am not going to keep going back to see which one you replied to. Stay with one posting please. I just notice one way down the list where you did part a) Calculate the area on top of the

asked by Reiny on April 22, 2010
69. ## medical billing

How do you calculate the DRG reimbursement for a Medicare surgical craniotomy case with relative weight of 3.0970 and a geometric mean length of stay of 6.3 with the hospital's current standard reimbursement rate of \$1500.00?

asked by Gwen on February 10, 2010
70. ## Chem

the standard molar enthalpy and entropy of the denaturation of a certain protein are 512 kj/mol and 1.60 kj/K. mol, respectively . comment on the sign s and magnitudes of these quantities, and calculate the temperature at which the process favors the

asked by Cece on March 4, 2012
71. ## CHEMISTRY

24cm^3 of a mixture of methane and ethane were exploded with 90cm^3 of oxygen. After cooling to RTP the volume of gases was noted and it decreased by 32cm^3 when treated with KOH. Calculate the composition of the mixture.

asked by LC on October 23, 2012
72. ## Physics

A 5.o kg box is lifted to a height of 10 meters at a constant speed. a)How much power is required to complete this task in 10 seconds? b)Calculate the velocity of the box just as it hits the ground? i have the answers but i need a second opinion a)50 watts

asked by Mexico on April 6, 2011
73. ## Statistics

When the Indianapolis Colts recently won the Super Bowl, the numbers on the jerseys of the active players were 29, 41, 50, 58, 79,..., 10 (listed in the alphabetical order of the player's names). Does it make sense to calculate the mean of those numbers?

asked by Andrea on April 8, 2011
74. ## Chemistry

using a coffee calorimeter, it is found that when an ice cube weighing 24.6g melts, it absorbs 8.19kJ of heat. calculate delta H for the phase change represented by the thermochemical equation: H2O(s) ->H2O(l)

asked by Kera on April 21, 2014
75. ## !chemistry !experiment!

Design an experiment which is not a tritation, you could use to calculate the percentage of water of crystalallization in NA2CO3.xH20. Need apparatus, detailed method including precutions and assumptions, how the results are recorded and how the percentage

asked by Cameron on June 1, 2010
76. ## Chemistry

Assuming that seawater has a total ion concentration (aka colligative molarity) of 1.10 M conc, calculate how many liters of seawater are needed to produce 68.7 L of fresh water at 20 C with an applied pressure of 51.0 bar.

asked by Michael Stoll on January 11, 2014
77. ## physics

A dynamite blast at a quarry launches a chunk of rock straight upward, and 2.0s later it is rising at a speed of 15m/s. Assuming air resistance has no effect, calculate its speed A) at launch and B) 5.0s after lauch

asked by Natasha on January 29, 2012
78. ## engineering

An oil company has to pay \$10000 per year starting one years from today on a loan obtain for 5 years at an effective interest rate of 8%. Calculate the equivalent present value of this 5 yearly annuity.?

asked by poppy on May 1, 2019

calculate the amount that will be accumulated after 20 years if \$1600 is invested at the beginning of every six months at 13.5% compounded semi annually. Do not round intermediate calculations, just round the final answer to 2 decimal places

asked by aiman on November 3, 2014
80. ## Trig Help

Given the equation for simple harmonic method d=1.3cos(3pi/4 t) answer the following questions: a)Find the maximum displacement. 1.i got 1.3 b)Find the frequency and length of the pendulum c)Calculate the value of d when t=3 i got .919 d)Determine the

asked by Ryan on March 24, 2016
81. ## physics

a stone attached to the end of elastic string is whirled around in a circular path of radius 20cm if the stone makes 15 complete revolution in 5 seconds, calculate its angular and linear velocities.

asked by isah a on March 29, 2017
82. ## College Chem

A 2.446-g sample thought to contain only one volatile substance, MgCO3, was heated in a nitrogen atmosphere for 30 min. After cooling, the residue weighed 2.216 g. Calculate the percentage of magnesium carbonate in the sample.

asked by Ann on January 16, 2012
83. ## chemistry

A hypothetical pure element consists entirely of two isotopes. The natural percent abun- dance of theisotopewithmass 25.4 uis 82.6%. The other isotope has mass 29.5 u. Calculate the atomic weight of the naturally occurring element.

asked by chanel on September 15, 2014
84. ## Physics

A 5.o kg box is lifted to a height of 10 meters at a constant speed. a)How much power is required to complete this task in 10 seconds? b)Calculate the velocity of the box just as it hits the ground? i have the answers but i need a second opinion a)50 watts

asked by Mexico on April 6, 2011
85. ## Math

what is the sale price for a video game that was originally priced at \$59.99 and now is 10% off. 1 50.99 2 53.99 3 55.24 4 58.99 Calculate the interest earned on a saving account with 660.00 that is invested at 3.5% annual simple interest for 5 years 1

asked by asdflk;jasdfla;kjsdfl; on December 18, 2015
86. ## physics

An object of mass 50kg moves at 50m/s round a circular path of radius 10m.calculate i)centripetal acceleration. ii)centripetal force need to keep it in it's orbits.. Please show all caculations detains.

asked by pete onoriode on March 18, 2011
87. ## Chemistry

Calculate the maximum wavelength of electromagnetic radiation capable of breaking the C-N bond in lysine. DATA: Average Bond Energies (kJ/mol) N-N 160 C-C 350 Express your answer in meters.

asked by selly on January 11, 2013
88. ## physics

A rough wooden block of mass 4kg place on a rough horizontal plank is applied by a force of 35n until it just starts to move calculate the coefficient of static friction (take 9=10m/52)

asked by Anaebo on November 15, 2011
89. ## chem

Calculate the number of liters of hydrogen, measured at STP, that can be produced from the reaction of 0.155 mol of aluminum according to the following unbalanced chemical reaction equation. i got .193 L of H2 but it was wrong. i only have one submition

asked by hannah on December 9, 2010
90. ## physics

An ice tray contains 490 g of liquid water at 0°C. Calculate the change in entropy of the water as it freezes slowly and completely at 0°C. i tired doing -(.49kg)(2.26x106)/273.15K) but im not getting the right answr help pls!

asked by tom on October 30, 2008
91. ## physics

a stone projected horizontally from the top of a tower with a speed of 4m/s lands on the level ground at a horizontal distance 25m from the foot of the tower. calculate the height[g=10m/s2]. is it u squared divided by 2g

asked by Emmanuel on August 3, 2015
92. ## College Chemistry

Calculate the unknown of Ag+ if the potential of the following concentration cell is 300 mV at 25.0 C. Ag|Ag+(unknown)||Ag+(0.100M)|Ag I think I have to use Nernst Equation of Ecell=E0-.0592/nlogQ And at 25C is at 298K so i don't have to change anything. I

asked by Samantha on May 6, 2015
93. ## physics check

A straight line 1.8m long carries a current of 13A and make an angle of 15º with a uniform magnetic field B=1.5T Calculate the magnetic force on the wire. Do we use F=I×L×B×sin in order to solve or no

asked by angy on May 31, 2016
94. ## physics

a 2kg and a 4kg hang freely at opposite end of a light in-extensible string which passes over a small and light pulley fixed to a rigid support.calculate the acceleration of the system.

asked by ali on April 20, 2012

Determine whether it is possible to draw a triangle given each set of information. Sketch all possible triangles where appropriate. Calculate then label all side lengths to the nearest tenth of a centimetre and all angles to the nearest degree. A) b= 3.0

asked by Mimi on April 6, 2015
96. ## chemistry

Delta H is given and is-6186.0 Calculate the difference, deltaH-deltaE=delta(PV) for the combustion reaction of 1 mole of methyl octane. (Assume standard state conditions and 298 K for all reactants and products.)

asked by BREE on November 14, 2009
97. ## Physics

A human has a reasonable chance of surviving an automobile crash if the body's deceleration is no more than 30 "g's". (1 "g" is 9.8 m/s^2) Calculate the force the body would have withstand decelerating at this rate. What is the distance travelled if the

asked by Anonymous on November 9, 2007
98. ## Chemistry

Write a balanced net ionic equation to show why the solubility of Ca(OH)2(s) increases in the presence of a strong acid and calculate the equilibrium constant for the reaction of this sparingly soluble salt with acid.

asked by Kat on May 27, 2016
99. ## Chemistry

A 0.1052 g sample of copper metal is dissolved in 55 mL of concentrated HNO3 to form Cu2+ ions and then water is added to make a total volume of 208.5 mL. (Calculate the molarity of Cu2+.)

asked by Ashley on June 21, 2013
100. ## Chemistry

A 0.1052 g sample of copper metal is dissolved in 55 mL of concentrated HNO3 to form Cu2+ ions and then water is added to make a total volume of 208.5 mL. (Calculate the molarity of Cu2+.)

asked by Ashley on June 21, 2013