# 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 237
1. ## Chemistry

Hi! I am totally stuck on this question: Explain why a cool flame is important to use in heating a solution to dryness. Can you please explain to me exactly why because I really do not understand. thank you!

asked by Abigail on September 9, 2015
2. ## math

What does "give a brief explanation as to what kind of solution(s) you expect the linear equation to have: 18x+1/2=6 (3x+25). Transform the equation into a simpler form if necessary" mean?

asked by Samantha on January 23, 2014
3. ## match check

Solve the following equation. 3(2x-6)=(6(x-3) a)0 b)1 c)all real numbers d)no solution is it a) 0? Write the number without exponents 3.44X10^10 is it 344,000,000

asked by Anonymous on December 16, 2008
4. ## chemistry

The heat of solution of potassium acetate in water is -15.3 ,What will be the final temperature when 0.132 is dissolved in 550 water that is initially at 25.1 ?

asked by Anonymous on April 1, 2013
5. ## History

What things need to be considered in finding a solution for the oil problem in the Middle East? What obstacles are there in solving the oil issue?

asked by Christian on February 25, 2008
6. ## Biochem

If .1ml of serum, 5ml of reagent and 4.9ml of distilled water are mixed together what is the dilution of the serum in the final solution

asked by Dave on March 23, 2014
7. ## trigoooo

find, to the nearest minute, the solution set of 4 cos x + 5 = 6 sec x over the domain 0 degrees which is less than or eaual to x which is less than 360 degrees

asked by Clarkney on May 17, 2010
8. ## chemistry

Determine the molarity of nitrate ions in a solution prepared by mixing 25.0 mL of 0.50 M Fe(NO3)3 and 35.0 mL of 1.00 M Mg(NO3)2 Please explain fully do not know where to start?

asked by Lisa on December 13, 2010
9. ## chemistry

In a 1.0x10^-4 M solution of HClO(aq), identify the relative molar amounts of these species:HClO, OH-, H3O+, OCl-, H2O

asked by karla on October 12, 2012
10. ## ALGEBRA

Solve the equation. (Enter solutions from smallest to largest. If there is no solution, enter NONE in the answer boxes.) 4x2 = 19x + 5 x = x =

11. ## IV calculations-medical math

Heparin is to infuse at 9ml/hr. the IV solution is 25,000units heparin in 250cc D5w. what is the hourly dosage? what is the drip rate?

asked by joyce on December 21, 2008
12. ## pharmacy calculations

If 500gm of dextrose are dissolved in 600ml of water, with the final volume being 1000ml, what is the percentage strength of the dextrose in the solution?

asked by Vicki on February 2, 2012
13. ## chemistry

The cola sample is 50. mL, the equivalence point volume is 13.4 mL, and the NaOH solution concentration is 0.025 M, what mass of H3PO4 was in the sample?

asked by Kris on August 11, 2010
14. ## Chemistry

What mass (grams) of sodium phosphate is required to precipitate all silver ions from 94 mL of a 0.332 M solution of silver nitrate?

asked by Shea on February 2, 2012
15. ## chemistry

Given that a 0.160 M HCl(aq) solution costs \$39.95 for 500 mL , and that KCl costs \$10/ton, which analysis procedure is more cost-effective?

16. ## biology

A plant is placed in bright sunlight. After a few hours, one of its leaves is stained with iodine solution. Which structure will be stained blue/black?

asked by Al on December 8, 2008
17. ## Chemistry

What minimum number of moles of NH4Cl must be added to 1.0 liter of solution that is 0.10 M in Mg(NO3)2 and 1.0 M in NH3 to prevent precipitation of Mg(No3)2?

asked by Ana on October 24, 2010
18. ## Chemistry Homework

Hello! Could someone help me with this? I'm confused on what to do. Thanks!! The mole fraction of carbon dioxide (CO2) in water is 0.25. Determine the molarity of CO2. The density of the solution is 1.0 g/mL.

asked by Amber on April 5, 2017
19. ## Operations research

36) Consider the following minimization problem: Min z = x1 + 2x2 s.t. x1 + x2 ≥ 300 2x1 + x2 ≥ 400 2x1 + 5x2 ≤ 750 x1, x2 ≥ 0 What is the optimal solution?

asked by Pauline on December 12, 2010
20. ## Precalculus -- Systems of Equations

I do not understand this problem. This is part of the question, but I think if I get this part, I'll get the rest. Determine the value(s) of r for which the system: (x^2)+(y^2)=(r^2) x-2y=8 has one real solution. I can't get anywhere! We should solve

asked by Dave on April 27, 2017
21. ## Chemistry

Find the pH during the titration of 20.00 mL of 0.1000 M butanoic acid, CH3CH2CH2COOH (Ka = 1.54e-5), with 0.1000 M NaOH solution after the following additions of titrant: 0 mL, 14.00 mL, 19.95 mL, 20.00 mL, 20.05 mL, 24.00 mL.

asked by James on November 23, 2011
22. ## chemistry

Need to write a brief description of the procedure required to make 900mL of a 0.5 M NaCl solution. The formula weight of NaCl is 58.4g/mole.

asked by Debbie on September 24, 2012
23. ## Chemistry

If the tongs used in the experiement were made of pure iron, what might happen if the tongs were allowed to remain in contact with the CuCl2 solution?

asked by Tommy on February 16, 2014
24. ## math

What does "give a brief explanation as to what kind of solution(s) you expect the linear equation to have: 18x+1/2=6 (3x+25). Transform the equation into a simpler form if necessary" mean?

asked by Samantha on January 23, 2014
25. ## Biology

Need to write a brief description of the procedure required to make 900mL of a 0.5 M NaCl solution. The formula weight of NaCl is 58.4g/mole.

asked by Debbie on September 23, 2012
26. ## Chemistry

So I mixed 25 mL of 0.002 M KSCN and 25 mL of water in a beaker. The solution was clear with no precipitants. But then it says the ions present in KSCN are: so i put K+,S2- , CN- is that right?

asked by Ana on November 28, 2010

flat roof that is 22Œ by 36Œ cylindrical cistern 12Œ high and 5Œ in diameter Rain falls on a flat roof that is 22Œ by 36Œ. The rain drains into a cylindrical cistern 12Œ high and 5Œ in diameter. Assume that all of the rain drains

asked by Towanda on December 9, 2009
28. ## CSI 115 Logic And Design

Hi I know you have got this same question ask to you a lot, but mine is for week 2 unstead of week 1. This week they want me to come up with and Create the Modular Design for the same subject as week 1, example underneath please. A small startup software

asked by Preston on January 13, 2011
29. ## chemistry

hello, I can't seem to solve this question. i tried to look up someone else who may have asked this question. I found this girl named Sara,but her answer didn't really help me much because it did not answer the question. What is the pH when enough 0.10 M

asked by THOMAS on July 12, 2010
30. ## chemistry

For 2SO2(g)+O2(g)⇌2SO3(g), Kp=3.0×104 at 700 K. In a 2.00-L vessel the equilibrium mixture contains 1.15 g of SO3 and 0.107 g of O2. 1) How many grams of SO2 are in the vessel? ---------------------------- A flask is charged with 1.500 atm of N2O4(g)

asked by whateva on January 31, 2018
31. ## thermodynamics and statistical machenics

Consider sun as a black body whose interior consist of photons gas at T = 3×10^6k. Calculate the energy density of the solar radiations. Take (sigma) = 7.56×10^-16jm^-3k^-4

asked by gourav on March 22, 2015
32. ## physics

From the moment a 42 m/s fastball touches the catcher's mitt until its completely stopped takes 0.014 s. Calculate the average acceleration of the ball as it is being caught.

asked by joe on November 6, 2012
33. ## math/science

"calculate the volume of 5g of a substance with a density of 6g/mL. SHOW ALL WORK" I just can't figure it out. D=M/V. But if you're making both sides equal? If someone could just explain. Because at first I thought it was 8.3, then 5/30, and I'm not asking

asked by Lena on May 30, 2008
34. ## maths

The mid-point of the straight line joining A(4,-3), B(6,-2) is located at C. (a) Calculate the coordinates of C. (b) Verify your result by calculating the distances AC and BC and showing they are equal.

asked by Jared on October 31, 2016
35. ## Physics

The length of a box is reduced to two third of its original value and the width and height are tripled. Calculate the factor by which the volume has changed. Am I on the right track? If not please help I am stuck. Thanks. V=LWH V=(L-2/3)(3W)(3H)

asked by Jane on June 4, 2014
36. ## physis

A ball of mass 80kg falls from rest from a height of 100m.neglecting air resistance, calculate it K.E after falling a distance of 30cm

asked by john on April 28, 2013
37. ## chemistry

The standard Gibbs free energy of formation of ammonia at 25 ° c is - 16.5kj per mole.calculate the value of equilibrium constant Kp at this temperature for this reaction. ( 5marks )

asked by muli on March 21, 2015
38. ## geometry

Using the following values, calculate the amount accumulated (future value): Initial Principal = \$9000 Interest Rate = 8% Number of years = 9 Monthly Compounding

asked by mike... on April 16, 2011
39. ## Physics

Calculate the magnitude of the linear momen- tum for each of the following cases a) a proton with mass 1.67 × 10−27 kg mov- ing with a velocity of 6 × 106 m/s. Answer in units of kg · m/s.

asked by Chris on January 19, 2015
40. ## Elementary mechanics

Given that the mass and radius of jupiter are respectively 190000000kg 7150000km.Calculate the escape velocity from the surface of the planet(a)11.2 km/s(b)33.3km/s(c)59.5km/s(d)110.4km/s

asked by jane on July 15, 2013
41. ## chemistry

3.5g of CuCl2.2H2O were dissolved and reacted with excess Na2SO3 in the presence of HCl. After filtration, 1.5g of CuCl crystals was obtained. Calculate the %yield.

asked by Shannon on November 14, 2011
42. ## chemistry

Calculate the volume of NaOH 0.1M that needs to be calculated to be added to a 30ml o-phosphoric acid 0.1 in order to prepare solutions of pH 7.5 and pH 6.9? pKa3= 2.15; pKa2=7.2; pKa1 = 12.1

43. ## Physics

The first leg of a relay race is semi circle of diameter 50m. If the runner covers the distance in 11s.calculate the average speedâ€

asked by Anonymous on February 17, 2018
44. ## General chemistry

If 10g of phosphine is made to react with 15g of chlorine gas, calculate the percentage yield if 5.5g of phosphorus pentachloride was experimentally produced

asked by Samuel on March 31, 2019
45. ## Reposting Chemistry College

Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react? Thanks.

asked by Lance on April 15, 2012
46. ## College Chem

Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react? Thanks.

asked by Lance on April 15, 2012
47. ## chemistry

A certain amount of gas occupy 5.0dm cube at 2atm.and 10 degree centigrade .calculate d number of mole present(R_0.082atm)

asked by favour on February 26, 2017
48. ## College Chem

Based on the balanced equation 4Na + O2 → 2Na2O calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react? Thanks.

asked by Lance on April 15, 2012
49. ## math

calculate,in terms of weight of 1kg, the force necessary to maintain a body of mass 147kg in uniform speed of 10m/s in a circle of radius 5m

asked by vicky on June 14, 2013
50. ## Physics

a boy stands at a distance of 175 m from a high wall. He claps his hands and hears an echo after one second. Calculate the speed of sound in air.

asked by Anonymous on August 18, 2017
51. ## physics

A swimmer is capable of swimming at 1.4m/s in still water. Calculate the following. i. How far downstream will he land if he swims directly across 180m wide river? ii. How long will it take him to the other side.

asked by Ashman on February 11, 2013
52. ## chemistry

A healthy adult exhales about 5.0*10 exponent 2 ml, of a gaseous mixture with each breath. calculate the number of molecules present in this volume at 37C and 1.1atm.

asked by silly on November 28, 2010
53. ## Physics

Calculate the total heat content of 10 kg of ice at -23°C. (Hint: absolute zero is -273°C.) Be mindful of significant figure rules for both multiplication and addition.

asked by Kathryn on December 10, 2012
54. ## physics

a cyclist moving with constant speed 10m/s develop a power of 400 watt. Calculate the average force exerting on the bicycle

asked by saber on April 29, 2013

The mid-point of the straight line joining A(4,-3), B(6,-2) is located at C. (a) Calculate the coordinates of C. (b) Verify your result by calculating the distances AC and BC and showing they are equal.

asked by Steven on October 31, 2016
56. ## science(physics)

a car of mass 100kg travering at 36km/h is brought to rest over a distance of 40m.calculate(a)accelaration(b)the average abreaking force

asked by luckson on January 28, 2016
57. ## physics

A thin 12 cm long solenoid has a total of 460 turns of wire and carries a current of 2.1 A. Calculate the magnitude of the field inside near the center.

asked by JOSE on April 3, 2010
58. ## Calculus

Find the positive value of x which satisfies x = 4.3cos(x). Give the answer to six places of accuracy. Remember to calculate the trig functions in radian mode

asked by J on July 17, 2013
59. ## physics

12.5 kg wooden crate with an initial velocity of 2.5 m/s slides across a rough cement floor for 1.7 m before coming to rest. Calculate the coefficient of kinetic friction

asked by Anonymous on October 29, 2012
60. ## physics

calculate the volume in cubic centimeters and area in square millimeters of a spherical bacterium of diameter 2.0um. model the bacteria is spheres

asked by Sue on November 30, 2016
61. ## Chemistry

calculate the wavelength in nm of the spectral line produced when an electron in an hydrogen atom undergoes the transition from n=3 to n=2. I get 6.56x10^-7 meters and 6,561.68 nm but that is not the right answer...help please!

asked by Jana on January 14, 2013
62. ## physics

A load of mass 80kg fell dwn from d floor of a lorry whch is 1.2m high.calculate wrk dne by gravity on d land

asked by Emeka on November 15, 2011
63. ## chemistry

(a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

asked by student on December 14, 2012
64. ## chemistry

(a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

asked by lena on December 14, 2012
65. ## Math

This seems like it would be a simple math problem but...... How do you create an equation and calculate the difference between 2 birthdays, putting the older person's on top? 5/17/1987 and 10/28/2002 PLEASE HELP ME!

asked by Josh on May 20, 2014
66. ## physics

Charged spheres A and B are in fixed positions (like in question #6) and have charges 3.6x10^-6 C and -5.4x10^-6 C respectively. Calculate the net force on sphere C, which has a charge of -9.9x10^-6 C.

asked by help on May 6, 2013
67. ## AP Chemistry

Calculate ΔHrxn for the following reaction: C(s)+H2O(g)→CO(g)+H2(g) Use the following reactions and given ΔH values: C(s)+O2(g)→CO2(g), ΔH= -393.5 kJ 2CO(g)+O2(g)→2CO2(g), ΔH= -566.0 kJ 2H2(g)+O2(g)→2H2O(g), ΔH= -483.6 kJ

asked by Q on December 7, 2015
68. ## ap chemistry

A sample of gas in a cylinder of volume 4.09 L at 289 K and 3.43 atm expands to 7.73 L by two different pathways. Path A is an isothermal, reversible expansion. Calculate the work

asked by cheri on October 31, 2012
69. ## Physics

Calculate the magnitude of the linear momen- tum for each of the following casesEarth (m = 5.98 × 1024 kg) moving with an orbital speed equal to 26200 m/s. Answer in units of kg · m/s.

asked by Chris on January 19, 2015
70. ## physics

A uniform chain 10m long and weighing 6 kg permetre hangs vertically.calculate the work required to wind it up.. Plzz solve it

asked by arya on November 23, 2015
71. ## chem.

Calculate the amount of heat required to raise the temperature of a 25 g sample of water from 5°C to 10.°C. i got 523 then rounded it to two sig figs 520 but it said it was wrong

asked by Rebekah on September 15, 2010
72. ## Chemistry

A 4.00g piece of magnesium is added to 200mL of 1.40 mol/l HC. Identify the limiting reactant, and calculate the mass of hydrogen gas that should be produced

asked by Jeddediah on February 15, 2016
73. ## Chemistry/Math

Calculate the following and round to the allowed number of significant figures 1. (18.00 x 1.5) / 0.00625 2.4.61 X 10^3 / 5.1008 x 10^-4 My answers 1. 4320 2. 9.037 x 10^-1 Please explain what I did wrong if I'm incorrect. Thank you

asked by Clare on January 22, 2015
74. ## physics

Three charged particles are placed at the corners of an equilateral triangle of side d = 1.40 m (Fig. 16-53). The charges are Q1 = +4.0 µC, Q2 = -7.0 µC, and Q3 = -6.0 µC. Calculate the magnitude and direction of the net force on each due to the other

asked by CLaire on January 30, 2012
75. ## Physics

A metal disc of radius R rotates with angular velocity Omega (w) In a uniform magnetic field. Calculate the induced emf develop.

asked by Srv on August 27, 2017
76. ## Math

This seems like it would be a simple math problem but...... How do you create an equation and calculate the difference between 2 birthdays, putting the older person's on top? 5/17/1987 and 10/28/2002

asked by Josh on May 20, 2014
77. ## chemistry thermodynamics

a sample of methane gas of mass 25g at 250k and 18.8atm expands isothermally until its pressure is 2.5atm. calculate the change in entropy.

asked by sam on October 19, 2013
78. ## physics!!!

For the vectors with a = 14, b = 13, and c = 365, calculate the following dot products. NOTE theres a picture but i couldn't upload its a right angle triangle with c as the hypt, a bottom and b side

79. ## physics help!!

A hypothetical spherical planet consists entirely of iron (p=7860kg/m^3). Calculate the period of a satellite that orbits just above its surface. I really can't solve this! No other information was provided. Please and thank you

asked by Anonymous on March 3, 2010
80. ## physics help!!!

A hypothetical spherical planet consists entirely of iron (p=7860kg/m^3). Calculate the period of a satellite that orbits just above its surface. I really can't solve this! No other information was provided. Please and thank you

asked by Anonymous on March 3, 2010
81. ## Geology maps

An environmental restoration project requires that you enlarge part of the map to a scale of 1 inch to 1000 feet. Calculate the factor by which it needs to be enlarged.

asked by Roger on March 3, 2011
82. ## Physics

A hypothetical spherical planet consists entirely of iron (p=7860kg/m^3). Calculate the period of a satellite that orbits just above its surface. I really can't solve this! No other information was provided. Please and thank you

asked by Anonymous on March 3, 2010
83. ## Engineering

The maximum retardation of a lift is 3m/s squared. Calculate the shortest time required to bring it to rest from a speed of 9m/s. What is the distance travelled in this timr

asked by Foibe on May 6, 2019
84. ## chemistry

Calculate the volume of gas you would expect to be evoleved if X mol of magnesium were reacted with an excess of HCl at standard conditions. Would the answer be X, 22.4X, or 22400X?

asked by Stephanie on November 24, 2012
85. ## Chemistry

Calculate how many grams of the product(s) would be produced by complete reaction of 0.125 mole of the first reactant. CaCO3 + 2HCl --> CaCl2 + CO2 + H2O

asked by Lindsey on April 22, 2012
86. ## science

mgco3 plus 2hcl plus mgci2 plus h2 h20 plus co2 if 10grames of c02 is produced calculate the mass of magnesium and hydrochoric acid reacted

asked by josh on August 29, 2012
87. ## physics

In a carnival ride,passengers travel in a constant speed in a circle of radius 5m and make 1 complete revolution in 40s. calculate the acceleration?

asked by poppy👌🤔 on May 5, 2019
88. ## physics

to tighen a nut you exert 15N of force on wrench, which is a distance of 0.50m from pivot point. calculate amonut of torque produced...

asked by deb on August 23, 2010
89. ## math

a millionaire leaves 1.4 million dollars in his will to be shared between his three children in the ratio of their ages. if they are 24,28,32 years old, calculate to the nearest dollar the amount they will each receive? PLEASE HELP!!!

asked by Anonymous on September 23, 2011
90. ## Physics

Calculate the pressure exerted by 75 cms of vertical length of a water column in SI units. Options: A. 7390Pa. B. 7560Pa. C. 7250Pa. D. 7350Pa.

asked by G. Samuel Frank on November 5, 2015
91. ## physics

The masses of these particles are mA = 374 kg, mB = 516 kg, and mC = 155 kg. d1 = 0.414 m and d2 = 0.207 m. Calculate the magnitude of the net gravitational force acting on particle A.

asked by Anonymous on September 22, 2014
92. ## physics

A simple harmonic oscillator executes motion whose amplitude is .20 m and it completes 60 oscillations in 2 minutes Calculate its time period and angular frequency

asked by Anonymous on February 18, 2015
93. ## Physics

A car takes a turn with the radius of 150 m at the speed of 30m/s. a) Calculate the acceleration at 60 degree angle around the curve. the answer is 5.7m/s2, What formula do I use ?

asked by Physics: Circular Motion? on May 17, 2014
94. ## Chemistry

Based on the balanced equation 2Ba + O2 → 2BaO calculate the number of BaO formula units formed when 54 Ba atoms and 21 O2 molecules react?

asked by Leslie on February 15, 2010
95. ## math

a conductor having a cross sectional area of 0.00161 sq. in. carries a current of 4.5 amp. Calculate the electron velocity, assuming the wire to be a copper.

asked by Anonymous on May 18, 2017
96. ## chemistry

Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

asked by cutie on December 16, 2012
97. ## Math

A triangular pyramid measured 10cm by 7cm has a height of 11cm.calculate to the nearest whole number 1)total surface area 2)volume

asked by Precious on May 7, 2019
98. ## Physics, diffraction, interference, help!

3.Blue light (λ = 450 nm) shines on a diffraction grating that has 4000 lines/inch. A.Calculate the angle of the fourth-order image

asked by Jamie on April 8, 2013