# Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. 2x + 10y = 58 -14x + 8y = 140

91,718 questions, page 243
1. ## English 1

In "A Cub Pilot" what does the author mean when he says the Mississippi is "fickle"? A- the river provides work for many pilots B- the river is only one of the many pilots that can work. C- the river often floods, endangering the people that live near it

asked by Skye on September 12, 2014
2. ## algebra 1

It certainly pays to check your work! I just took a huge science test. I checked it over twice before I turned it in, and I got an A! My score was 94 out of 100! I figure that each time I checked it, I found half of the mistakes that were there at a time.

asked by Eternal on December 19, 2012

There are at least 5 more than twice as many students taking algebra 1 than taking algebra 2. If there are 44 students taking algebra 2, what is the least number of students who could be taking algebra 1. Show all work

asked by lee on November 20, 2008
4. ## urgent chem help ( dr bob plz)

A particular household ammonia solution (d= 0.97g/mL) is 6.8% NH3 by mass. How many milliliters of this solution should be diluted with water to produce 650 mL of a solution with pH = 11.50? ============================ first i did was ph = 11.50 PH=

asked by javeya on February 17, 2009
5. ## Econ MC

Dick owns a dog whose barking annoys Dick's neighbor Jane. Dick receives personal benefit from owning the dog, and Jane bears a cost of Dick's ownership of the dog. Assuming Dick has the legal right to keep the dog, which of the following choices are true?

asked by Econ on April 17, 2007

Solve the following; use proper fractions in your answer: 1. 1/3 + 1/4 = 7/12 2. 4/5-2/3 = 2/15 3. 5/6 * 4/5 = 2/3 4. 3/7 divided by 6/8 = 4/7 5. 3 1/4 - 1 3/8 = 1 7/8.....is this a proper fraction? 6. 5 8/9 + 2 4/7 = 8 29/63..is this a proper fraction?

asked by anonymous on August 18, 2006
7. ## chemistry

what evidence supports the clarification that H2Se 03 is an acid and how do i identify the positive ions present inthe aqueous solution I am a little confused by the word "clarification" in your question. What evidence do you have? Could you measure the pH

asked by mickey on January 30, 2007
8. ## Chemistry

Calculate how many grams of sodium azide (NaN3) are needed to inflate a 25.0 × 25.0 × 20.0 cm bag to a pressure of 1.25 atm at a temperature of 20.0°C. How much sodium azide is needed if the air bag must produce the same pressure at 10.0°C? 20.0°C:

asked by Onye on March 4, 2018
9. ## Chemistry

You are trying to find the heat (qrxn) in joules. C is 4.19 Change in temp is -2.2 I don't know how to find the mass if they tell me that the density of the solution is 1.02 and that the volume of water is 100 mL (Should I use the mass of the solution I

asked by Sary on November 3, 2017
10. ## chemistry

Please help. Concentrated hydrochloric acid is a 38% w/w solution of HCL in water and has a density of 1.18g/ml. How many millilitres of concentrated hydrochloric acid are needed to prepare 500ml of a 1:200 w/v HCL solution? My answer is 2.12ml. I'm not

asked by Peter on May 7, 2012
11. ## Chemistry

a 15ml sample of sulfuric acid was titrated against a solution of .0100 mol per litre of sodium hydroxide. to bring about neutralization, 25.00 ml of sodium hydroxide solution was required. calculate the concentration of the sulfuric acid

asked by Omaaaaaaaar on January 24, 2013
12. ## Chemistry

You extract the iron from a tablet and dilute that to 250.0 ml in a volumetric flask. You transfer 0.400 ml of this solution to a 25.0 ml volumetric flask and dilute this to volume. When you measure the concentration of this solution, you find that it is

asked by Spider on April 11, 2013
13. ## Chemistry

A solution of potassium hydroxide is in equilibrium with an undissolved solute at 45 degrees Celsius. What will happen to the mass of the potassium hydroxide if the temperature is raised to 50 degrees Celsius? (Given that heat of solution is

asked by Dayton on December 14, 2012
14. ## Chem2

Copper(II) iodate precipitates from iodate solution. The formula of the precipitate is CU(IO3)2. A saturated solution of this substance was made in 0.01 M KLO3. The copper concentration was found to be 0.0013 M. Determine the [IO3-] and Ksp of the

asked by Sammie on October 12, 2010
15. ## chemistry

In the following experiment, a coffee-cup calorimeter containing 100 mL of H2O is used. The initial temperature of the calorimeter is 23 degrees Celsius. If 4.00 g of CaCl2 is added to the calorimeter, what will be the final temperature of the solution in

asked by Katherine on October 19, 2009
16. ## chemistry

Concentrated phosphoric acid,H3PO4 was added slowly into some water to produce 5.0dm^3 of a dilute acid solution.100g of the pure phosphoric acid,H3PO4 was present in the solution.Find the concentration of the acid,in g dm^-3.

asked by mandy on May 5, 2014
17. ## chemistry

At 29.6 degrees C, pure water has a vapor pressure of 31.1 torr. A solution is prepared by adding 86.7 g of "L" a nonvolatile nonelectrolyte to 390.0 g of water. The vapor pressure of the resulting solution is 27.6 torr. Calculate the molar mass of "L"

asked by J on February 13, 2015
18. ## chemistry

suppose that you have a micro pipet which delivers 100 drops per cubic centimeter, and a solution of 5.0% by volume of oil in alcohol. if you had used 10 drops of this solution, how many cubic centimeters of pure oil would be left after evaporation of the

asked by diana on September 18, 2016
19. ## Chemistry

A buffer is prepared by mixing 0.30 mole of formic acid (HCNO2) and 0.20 mole of sodium formate (NaCHO2) in enough water to make 0.50 liter of solution. Ka of formic acid is 1.7 x 10-4. Calculate the pH of the resulting buffer solution.

asked by Sam on March 7, 2012
20. ## chemistry

You extract the iron from a tablet and dilute that to 350.0 ml in a volumetric flask. You transfer 0.500 ml of this solution to a 75.0 ml volumetric flask and dilute this to volume. When you measure the concentration of this solution, you find that it is

asked by Kelcie on October 28, 2012
21. ## science

Please help. Concentrated hydrochloric acid is a 38% w/w solution of HCL in water and has a density of 1.18g/ml. How many millilitres of concentrated hydrochloric acid are needed to prepare 500ml of a 1:200 w/v HCL solution? My answer is 2.12ml. I'm not

asked by Peter on May 9, 2012
22. ## College Chemistry Lab

Determine the molarity of FD&C Yellow #5 in the following solution that's prepared by mixing the dye solution with water and alcohol. None of the solutes react with one another. 6.35x10^-5M FD&C Yellow #5 = 6.50mL deionized water = 6.50mL ethyl alcohol =

asked by L** on March 16, 2010
23. ## CHEMISTRY HELP!!

Formic acid (HCHO2) is a component of bee stings. It is a weak acid and dissociates according to the equilibrium shown below: HCHO2 H+ + CHO2- Kc = 1.8 x 10-4 For a 0.5 M solution of formic acid, we wish to determine the equilibrium concentration of H+.

asked by carlo on April 28, 2011
24. ## physics

A physical pendulum is constructed of a 48 cm long piece of wooden dowel with a mass of 550 grams and a radius of 0.7 cm. Attached at one end of the pipe is a hoop with a radius of 6 cm and a mass of 1.2 kg as shown. The pendulum is released from the 12:00

asked by Jessica on January 23, 2015
25. ## science(chem&statistics)

I have to write a abstract for my paper I was wondering if it was better to write it at the beginning or the end of the lab report. If I was to eliminate 1 value as an outlier would I go and include that in calculations of the RSD? I would assume not since

asked by christina on July 12, 2007
26. ## Plz -- Chem Help

Posted by Rushi on Sunday, March 15, 2009 at 3:35pm. Question.. Nicotinic acid (niacin) is a monoprotic acid with the formula HC6H4NO2. A solution that is 0.012M in the nicotinic acid has a pH of 3.39 at 25C. what is the acid-ionization constant, Ka and

asked by A on March 18, 2009
27. ## Pre-Cal

An equation is given. (Enter your answers as a comma-separated list. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.) 2 cos 2θ − 1 = 0 a). Find all solutions of the equations answer--> θ= (π+6nπ)/6 ,

asked by Amber on July 11, 2016
28. ## chemistry

A solution is made by dissolving 46.5g of urea, (CH4N2O) a nonelectrolyte, in 316g of water. Calculate the vapour pressure of this solution at 40 oC. (ans in torr, note the vapour pressure of pure water at 40 oC is 55.3 torr.) I have been struggling with

asked by wini on February 17, 2011
29. ## Chemistry

You have a stock 0.100 M solution of KMnO4 and a series of 100-mL volumetric flasks. What volumes of the stock solution will you have to pipet into the flasks to prepare standards of 1.00, 2.00, 5.00, and 10.0x10^-3M KMnO4 solutions? I tried using

asked by confused on March 19, 2013
30. ## chemistry

When 25.0 mL of 1.0 M H2SO4 is added to 50.0 mL of 1.0 M NaOH at 25.0 °C in a calorimeter, the temperature of the aqueous solution increases to 33.9 °C. Assuming the specific heat of the solution is 4.18 J/(g·°C), that its density is 1.00 g/mL, and

asked by nobody on March 14, 2013
31. ## Chemistry

At 21.0 °C, a solution of 23.71 g of a nonvolatile, nonpolar compound in 30.64 g of ethylbromide, C2H5Br, had a vapor pressure of 319.7 torr. The vapor pressure of pure ethyl bromide at this temperature is 400.0 torr. Assuming an ideal solution, what is

asked by Luke on July 14, 2014
32. ## chemistry

The volume of an aqueous solution of NaCl at 25oC is expressed as a function of the amount m in 1kg of solvent in the following form; V/cm3 = 1000.94 + 16.4 (m/mol) + 2.14 (m/mol)3/2 - 0.0027 (m/mol)5/2 Find the partial molar volume of NaCl and water in 1

asked by pritisha on August 13, 2018
33. ## Chemistry

CaCl2(s) Ca2+(aq) + 2 Cl-(aq) H = -81.5 kJ A 14.0 g sample of CaCl2 is dissolved in 130. g of water, with both substances at 25.0°C. Calculate the final temperature of the solution assuming no heat lost to the surroundings and assuming the solution has a

asked by Joe on November 10, 2007
34. ## chem

An impure sample of (COOH)2 ·2 H2O that has a mass of 3.4 g was dissolved in water and titrated with standard NaOH solution. The titration required 42.7 mL of 0.156 molar NaOH solution. Calculate the percent (COOH)2 · 2 H2O in the sample. Answer in units

asked by lois on April 3, 2016
35. ## Physics

Two identical massless springs of constant k = 200N/m are fixed at opposite ends of a level track, as shown. A 5 kg block is pressed against the left spring, compressing it by 0.15m. The block is then released from rest. The entire track is frictionless

asked by Anonymous on October 26, 2016
36. ## Physics

A cart of mass M1 = 6 kg is attached to a block of mass M2 = 3 kg by a string that passes over a frictionless pulley. The system is initially at rest and the table is frictionless. After the block has fallen a distance h = 1 m: What is the work Ws done on

asked by Jamila on June 13, 2006
37. ## Social Studies

Which method of showing Earth's surface is the most accurate? A. An equal-area projection B. A scale-model globe C. A Mercator projection D. A Robinson projection

asked by Kimberly on August 14, 2018
38. ## heathCare

I don't under stand can some help me?? A. List 2 examples of when you would use one of the various sampling techniques in the health care profession? B. When might you use one sampling technique over another? C. State the drawbacks of each sampling method.

asked by Danny on November 12, 2008
39. ## Math

14) Consider the parabola with equation y = x^2 - 6x + 5. a. Use any suitable method to determine the coordinates of the turning point of this parabola. b. Hence, state for which values of c the line y = c will intersect the parabola: i. twice ii. once

asked by Anonymous on September 20, 2018
40. ## English

1. He doesn't go to work every Sunday. 2. He doesn't go to work on Sundays. 3. He sometimes go to work on Sunday, and sometimes doesn't go to work on Sunday. 4. He doesn't go to work on any Sunday. [Does #1 mean #2? Are both the same? Does #1 mean #3 or

asked by rfvv on April 2, 2018
41. ## statistics

a raido show host asked people to call in and wheater they support new legislation to promote cleaner sources of energy. based on this sample, she constructed a confidence interval to estimate the proportion of all listners to her show who support the

asked by Nicole on May 6, 2012
42. ## physics

a mechanic uses a chain and bloc pulley to lift a 875-kg engine 4.0 m to the top of the garage. the downward force on the chain over the 4.0 m distance is 5.0 x 10^4 N. a)calculate the work done in raseing the motor b)how much useful work was done c)what

asked by tyler on January 12, 2013
43. ## Statistics

John drives to work each morning and the trip takes an average of μ = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of σ = 5 minutes. For a randomly selected morning, what is the probability that John’s

asked by Robbie on October 14, 2012
44. ## Statistics

John drives to work each morning and the trip takes an average of m = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of s = 5 minutes. For a randomly selected morning, what is the probability that John's

asked by Anonymous on October 1, 2011
45. ## statistics

John drives to work each morning and the trip takes an average of  = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of  = 5 minutes. For a randomly selected morning, what is the probability that John's

asked by karla on April 17, 2011
46. ## art

hi do you have any ideas for the following project: i need to pick any environment and document a message or issue about it in that exact environment, e.g. take a photo of my work in that place. i'm thinking about focusing on the issues of energy wastage

asked by anonymous on November 28, 2009
47. ## statistics

John drives to work each morning and the trip takes an average of µ = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of ó = 5 minutes. For a randomly selected morning, what is the probability that John’s

asked by gina on March 4, 2012
48. ## math

John drives to work each morning and the trip takes an average of µ = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of σ = 5 minutes. For a randomly selected morning, what is the probability that John’s

asked by Anonymous on March 4, 2013
49. ## Conceptual Physics

While driving down an icy road in his pickup truck, Dan slid off the road into a ditch. He and his two friends each exerted a force of 200 N on the truck for two minutes, but failed to move it. The work done by the three friends on the truck was? the

asked by Stacy on November 8, 2016
50. ## Statistics

John drives to work each morning and the trip takes an average of µ = 38 minutes. The distribution of driving times is approximately normal with a standard deviation of s = 5 minutes. For a randomly selected morning, what is the probability that John’s

asked by Anonymous on November 13, 2016

I couldn't find the sets of factors that add up to -13 in this problem. I have to solve this problem by factoring, not anything like the -b/2a or anything. Plz help, anything is greatly appreciated! x^2-13x+36 Thx for helping ppl! Emily, Couldnt it be

asked by Emily on February 12, 2007
52. ## College essays - Law

Hi, I have three essay questions for my constitutional law class that have been stumping me for some time. 1) The Q: Justice Brown concluded in Plessy v. Ferguson that if "the enforced separation of the two races stamps the colored race with a badge of

asked by John on January 1, 2010
53. ## chemistry

A certain substance has a solubility of 12 grams in 100 grams of water at 20°C. This means that _____ the substance will begin to dissolve when 12 grams are present in solution when 12 grams of the substance are stirred into a beaker with 100 g of water,

asked by Bleaktuber on January 24, 2019
54. ## Chemistry DrBob

I don't understand how you get the answer. I really don't understand any of this, how do I set it up with the numbers? once i get how to do this, then i feel i will understand how to set these up from here on out. so if you could, show all your work,

asked by Ben on April 27, 2011
55. ## Algebra

1.) Use the distributive Property to simplify the expression . (-1)(4 - c) A. 4 - c B. -4 + c C. 4 + c D.-4 - c 2.)Use the distributive Property to simplify the expression 4(2x - 4) A.8x + 4 B.8x - 4 C.8x - 16 D.4x - 16 3.) Use the distributive Property to

asked by Math is going to be the death of me on September 5, 2018
56. ## Language Arts

Think about the work you completed in your reading character role. Determine the ideas that would be most worthy to share in a literary discussion about Dragonwings. Provide an explanation for your choices. How did the role you selected and the work you

asked by PLZ HELP on June 12, 2017
57. ## chemistry

Hy Dr Bob222 this will be the last time I will bother you about this type of question. Can you please tell what I am doing wrong? This is the best answer I could come up with: Question: Strychnine, C21H22N2O2(aq) is a weak base but a powerful poison.

asked by Kelsy on April 8, 2008
58. ## work force

a force of 10 pounds is required to stretch a spring of 4 inches beyond it's natural length. assuming hooke's law applies, how much work is done in stretching the spring from its natural length to 6 inches beyond its natural length. what i did so far:

asked by david on April 13, 2007
59. ## math urgent

The state lottery (which has a 6% lottery tax) offers to pay winnings in 25 annual payments or one lump sum, sometimes called a cash-out option. This week’s lottery has a jackpot of \$30 million and a cash-out value of \$18.2 million. Granted that the odds

asked by sarah on March 4, 2018
60. ## math

The state lottery (which has a 6% lottery tax) offers to pay winnings in 25 annual payments or one lump sum, sometimes called a cash-out option. This week’s lottery has a jackpot of \$30 million and a cash-out value of \$18.2 million. Granted that the odds

asked by sarah on March 3, 2018
61. ## physics

How much work does the electric field do in moving a proton from a point with a potential of +120 V to a point where it is -60 V? Express your answer in joules. I've looked through my notes, and I'm sure the answer is really easy, but I'm not seeing it. I

asked by Morgan on September 6, 2010
62. ## English Language Arts

Think about the work you completed in your reading role. Determine the ideas that would be most worthy to share in a literary discussion about Walk Two Moons. Provide an explanation for your choices. How did the role you selected and the work you completed

asked by Jalon on May 24, 2017
63. ## Social Studies

How did Reconstruction affect daily life in south Carolina? A. Carpetbaggers and scalawags had less of an influence on the state.**** B. Northerners and freedman had more opportunities in the state. C. African Americans families received 40 acres and a

asked by Lost on March 24, 2016

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
65. ## 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
66. ## chem

how to find mass of aspirin if I used 0.2845g of the powder(crushed apririn) with 1mL of 6.0 mol/L of Nacl? Does the dilution(the above chemicals are diluted in a 500mL volumetric flask) matter ,and does adding the HCL/Fe^3+ stock solution in the end

asked by linda on April 23, 2015
67. ## Math

I'm struggling with the equations for the following problem: a) The sales representative informs you that there are two floor plans still available, and that there are a total of 56 houses available. Use x to represent floor plan #1 and y to represent

asked by Jen on March 22, 2009
68. ## Chemistry

The answeres to the previous post was not what I am looking for...so please try to help me..... How can I make various concentrations of CuSO4(this is a blue solution)? I know that to make 0.1M you would fill the copper solution up to 10mL in the graduated

asked by Anonymous on January 6, 2014
69. ## CHEMISTRY

The answeres to the previous post was not what I am looking for...so please try to help me..... How can I make various concentrations of CuSO4(this is a blue solution)? I know that to make 0.1M you would fill the copper solution up to 10mL in the graduated

asked by Anonymous on January 6, 2014
70. ## Chemistry

The answeres to the previous post was not what I am looking for...so please try to help me..... How can I make various concentrations of CuSO4(this is a blue solution)? I know that to make 0.1M you would fill the copper solution up to 10mL in the graduated

asked by Anonymous on January 6, 2014
71. ## Chemistry

A solution may conain the ions Ba^2+, Ag^+, and Cu2+. Add sodium chloride and get a white predipitate. The supernatant is decanted, potassium sulfate solution is added to the supernatant and no reaction is observed. Add sodium hydroxide and get a blue

asked by Mary on May 5, 2010
72. ## Chem

Using the standardized NaOH solution, the student weighs out 0.2550g of a solid unknown acid and finds that 28.50mL of the NaOH solution is required to reach an end point with the acid. Calculate the molar mass of the unknown acid, assuming the acid is

asked by Jen on April 25, 2014
73. ## Chem

Using the standardized NaOH solution, the student weighs out 0.2550g of a solid unknown acid and finds that 28.50mL of the NaOH solution is required to reach an end point with the acid. Calculate the molar mass of the unknown acid, assuming the acid is

asked by Jen on April 25, 2014
74. ## physics

a marble is dropped from the top of a skyscraper. Is the work done by earths gravitational force on the marble equal to, smaller than or larger them that done by the marbles gravitational force on earth? Why? newtons 3rd law: force on marble due to earths

asked by danielle on October 30, 2006
75. ## Chem

Hey in class we learned that pi molecular orbitals come from overlapping p atomic orbitals...this occurs in a conjugated system or aromatic rings ( contains sp2 carbons with one remaining p orbital which can can overlap to form double bonds)...my question

asked by Leena on February 23, 2013
76. ## chemitry

help me.. The pKa of acetic acid, HC2H3O2, is 4.76. A buffer solution was made using an unspecified amount of acetic acid and 0.30 moles of NaC2H3O2 in enough water to make 2.00 liters of solution. Its pH was measured as 4.40. How many moles of HC2H3O2

asked by Azy on April 24, 2015
77. ## chemistry

when 130.4 mL of 0.459 mol/L silver nitrate solution is mixed with 85.23mL of 0.251 mol/L aluminum chloride solution, a precipitate of silver chloride forms. Find the mass of this Precipitate.

asked by Emma on February 15, 2016
78. ## chemistry

A galvanic cell has an iron electrode in contact with 0.20 M FeSO4 and a copper electrode in contact with a CuSO4 solution. If the measured cell potential at 25 degrees Celcius is 0.61 V , what is the concentration of Cu2+ in the CuSO4 solution?

asked by jeff on May 17, 2011
79. ## Chemistry

The drug is a salt form while a molecular weight of 181.6G/mol. She needs a concentration of the stock solution of 100mM and she needs to make 1.2mL of the drug. How many grams will she need to weight out in order to make the stock solution?

asked by Totally Lost on July 1, 2014
80. ## Chem

Osmotic Pressure.. If the height of the column is 6 cm what is the osmotic pressure of the sugar solution in g/cm2 Assume the density of the solution is 1.01 g/ml.. Beaker of water with beaker of sugar solutution with semi permeable membrane

asked by donna on February 19, 2010
81. ## chemistry

what is the concentration of lead ions and sulfide ions in a saturated solution of lead sulfide (PbS) solution at 25 degrees celsius.

asked by Sam on May 9, 2010
82. ## Economics/English

How do you structure a policy essay? Like I have an economic problem (welfare) and my thesis is a solution to is. I have to write a policy/essay on my solution/problem.

asked by Labz on April 3, 2012
83. ## Chemistry

What volume (in mL) of 0.45 M Na2SO4 solution is needed to precipitate all the barium, as BaSO4(s), from 14.5 mL of 0.15 M Ba(NO3)2 solution? Ba(NO3)2(aq) + Na2SO4(aq)= BaSO4(s) + 2 NaNO3(aq)

asked by John on December 2, 2012
84. ## Chemistry

A solution of ammonia and water contains 1.60×1025 water molecules and 8.50×1024 ammonia molecules. How many total hydrogen atoms are in this solution?

asked by R on October 8, 2014
85. ## PRE-ALGEBRA

A nurse wishes to to add water to 60 ounces of 20% solution of benzalkonium chloride to dilute it to an 8% solution. How many ounces of water does she need to add?

asked by fAITH on October 6, 2009
86. ## Math

Search: a chemist is asked to make a 25% sodium chloride from 20 ml of a 20% sodium chloride solution. How much salt should she add to make it a 25% solution?

asked by Linda on March 29, 2011
87. ## chemistry

what is the concentration of lead ions and sulfide ions in a saturated solution of lead sulfide (PbS) solution at 25 degrees celsius.

asked by Sam on May 9, 2010

Six quarts of a 20% solution of alcohol in water are mixed with 4 quarts of a 60% solution of alcohol in water. The alcoholic strength of the mixture is. A. 80% B. 50% C. 36% D. None I HAVE NO IDEA HOW TO DO IT PLEASE HELP

asked by Cheng Bin on August 13, 2014
89. ## chemistry

A student needed to make 200 ml of 0.1 M naOH. If the stock soluton was 0.75 M, how much of the stock solution and how much wter would be needed to make this solution?

asked by Amy on May 4, 2011
90. ## chemistry

A chemist want to make a 10% Chlorine solution from 30% Chlorine solution and pure water. How much of the two should the chemist mix together to make 20mL. Please help with calculations. Thank you

asked by kate on August 31, 2012
91. ## Math

Write an equation that involves multiplication, contains a variable, and has a solution of 5. Then write another equation that has the same solution and includes the same variable and numbers but use divison.

asked by Anonymous on January 28, 2016
92. ## chemistry

A solution of ammonia and water contains 2.70×1025 water molecules and 7.60×1024 ammonia molecules. How many total hydrogen atoms are in this solution?

asked by Anonymous on October 9, 2011
93. ## Chemistry

Calculate [ClO^-] in a 6% bleach solution. A 6% bleach solution contains 6 grams of NaClO per 100 grams bleach. The density of 6% bleach is 1.07g/mL.

asked by Cassandra on February 27, 2012
94. ## math

Which statement concerning the equation x^2+2=x is true? Its discriminant is 0 , so it has no solution. Its discriminant is 0 , so it has one real solution. Its discriminant is -7, so it has two complex solutions. Its discriminant is -7, so its solutions

asked by Claire on May 9, 2016
95. ## Math

1. what is the solution of 87 + (-396)? A 183** B -183 C 9 D -9 2. Evaluate: -12 x 3 =? A 36 B -36** C 4 D -4 3. Evaluate: -20 ÷ -10 =? A 200 B -200 C 2 D -2*** 4. Select all the problems that have a solution that is negative. -8 + 10 = ? 8 x (-2) +? -4

asked by Frank on September 10, 2016
96. ## SCIENCE

Indicate how to mix two of the first concentration 3.2 M hydrochloric acid solution and the second to 15% by weight and density 1.30Kg / L to obtain 2.5 L of hydrochloric acid solution in 4.2M concentration

asked by ATTILIA on February 17, 2016
97. ## writing equations-Math

Write an equation that involves multiplication, contains a variable, and has a solution of 5. Then write another equation that has the same solution and includes the same variable and numbers but use divison.

asked by Anonymous on January 28, 2016
98. ## Chemistry

A solution of ammonia and water contains 3.70×1025 water molecules and 7.10×1024 ammonia molecules. How many total hydrogen atoms are in this solution?

asked by Mel on September 9, 2015
99. ## Chemistry

Calculate [ClO^-] in a 6% bleach solution. A 6% bleach solution contains 6 grams of NaClO per 100 grams bleach. The density of 6% bleach is 1.07g/mL.

asked by Cassandra on February 27, 2012
100. ## Chemistry

10.0 mL of a 0.300M NH3 solution is titrated with a 0.100M HCl solution. Calculate the pH after the following additions of HCl. 0.00mL 10.00mL 30.00mL 40.00mL

asked by Raven on March 30, 2013