# why does the equation x^2=-9 has no real solution why does the equation x^2 = 9 has two solutions

56,329 questions, page 494
1. ## chemistry

How many grams of ethanol must be added to 500.0 g of water to make a solution that freezes at 0.00 degrees fahrenheit? The molal freezing point depression constant for water is 1.86 degree celsius over moles.

asked by Renee on March 9, 2012
2. ## Chemistry

Suppose you are assigned to prepare a buffer of 0.10M HNO2 (Ka=1.7 x 10^-4) and 0.10M NaNO2 by mixing equal volumes of both solutions. What is the pH of the resultant solution? How would I first start this question? I have no clue what the steps are to be

asked by Janice on April 15, 2015
3. ## Calc Math

A plane is heading on a bearing of 200° with an air speed of 400 km/h when it is blown off course by a wind of 100 km/h from the northeast. Determine the resultant ground velocity of the plane. What was your solution to answering this problem?

asked by Amyy on February 22, 2015
4. ## world history

Hitler�s �Final Solution� referred to the extermination of the Jewish population living in and around Germany during the time of World War II. This resulted in the execution of over 6 million Jews. true or false I say its true

asked by tracy on January 22, 2012
5. ## chem

The dibasic compound B (pKb1 = 4.00, pKb2 = 8.00) was titrated with 1.00 M HCl. The initial solution of B was 0.100 M and had a volume of 100.0 mL. Find the pH at the following volumes of acid added and make a graph of pH versus Va; Va=0, 1, 5, 9, 10, 11,

asked by joshua on January 22, 2018
6. ## science/chemistry

I have the answer but how do you solve for this problem: What is the freezing point of a sugar solution prepared by dissolving 375.00g of sucrose (342.3g/mol) in 1500.0g of water (Kf of water=1.86 degrees Celcius)?

asked by Fisher on March 21, 2012
7. ## chemistry

Calculate the concentration of all species in a 0.130M solution of H2CO3 Enter your answers numerically separated by commas. Express your answer using two significant figures. [H2CO3], [HCO?3], [CO2?3], [H3O+], [OH?] =

asked by kales on May 6, 2015
8. ## Environmental science

Management and sustainability plan for deforestation.........I have the causes but when it comes to corrected the problem, I have several ideas, such as the UN funding program to pay countries such as Indoesnia to stop deforestation but this solution has

asked by linda on October 10, 2009
9. ## ALGEBRA1

to join the school swimming team, swimmers must be able to swim at least 500 yars without stopping. write an inequality describing which values of n will result in a swimmer making the team. graph the solution

asked by jenika on May 8, 2012
10. ## Dynamics

A boy running a foot race rounds a flat curve of 50 ft radius. If he runs at rate of 15 mph, at what angle with the vertical will be inclined his body? A.) 16.75° B.) 13.67° C.) 76° show solution step by step thanks

asked by Carl on July 14, 2018
11. ## Math

ceftriaxone (rocephin) is a dry powder antibiotic that must be reconstituted for use. the label states that to create a 100 mg/ml solution, 4.8 ml must be added to a 500mg vial. what is the powder volume. I am not sure what formula to use for this problem.

asked by Joyce on March 25, 2015
12. ## English

Does the wording sound alright in this sentence. War is the solution to the world's problems because global peace is impossible to achieve. Nothing is better than having that basic understanding on how in the end war would be justified and benefits

asked by Kara on May 4, 2009
13. ## Physics

I was wondering if my answers are correct. 1. A 50kg person is taking a ride on an elevator travelling up at a steady speed of 2.5m/s. Find the time fo the elevator trip if the elevator does 4900 J of work on the person. My answer: First I used the formula

asked by Liz on February 3, 2014
14. ## chemistry

Here is the full lab: Lab: Electrolytic Cells Purpose: The purpose of this experiment is to test the method of stoichiometry in cells. Materials: Balance Steel can Tin electrode Power Source Wire lead (x2) tin(II) chloride solution (3.25 M) Timer Large

asked by Reindier on April 18, 2008
15. ## macro

This year, a nations long run equilibrium real gdp and price level both increase. which of the following combinations of factors might simultaneously account for both occurances? a. an isolated earthquake at the begining of the year desroyed part of the

asked by aimee on September 8, 2010
16. ## economics

This chart shows the components of nominal GDP for the years 2000 and 2001. All figures are in billions of current dollars. Components 2000 2001 Consumption \$6,684 \$6,987 Investment \$1,755 \$1,560 Government Spending \$1,751 \$1,858 Exports \$1,101 \$1,034

asked by mary on September 23, 2016
17. ## chemistry

Hello, I have data here: tube # Contents Initial color (after 2 drops of universal indicator) Color after adding HCl Color after adding NaOH (after the HCl had been poured) 1 CO32-/HCO3- Dark purple Purple Purple 2 CO32-/HCO3- Dark purple -- -- 3 HCH3CO2/C

asked by Confused on April 19, 2012
18. ## math,algebra

Can someone help me put this into equations where i can solve them thanks. Problem #1 Allen bought 20 stamps at the post office in 37cents and 20cents denominations. If the total cost of the stamps was \$7.06, how many 37cents stamps did Allen buy? Problem

asked by jasmine20 on February 11, 2007

I need my answers checked for this question, thanks. A firm's production function: Q = 100 K^0.5 L^0.5 During the last production period, the firm operated efficiently and used input rates of 100 and 25 for labor and capital respectively. (a) What is the

asked by Bernice on March 10, 2007
20. ## finance

NikkiG’s Corporation’s 10-year bonds are currently yielding a return of 7.00 percent. The expected inflation premium is 1.20 percent annually and the real risk-free rate is expected to be 2.40 percent annually over the next ten years. The liquidity

asked by deda on November 26, 2016
21. ## Ela

CHOICES:pollute,pollution,protect,protection,inspect,inspection,impress,impression,migrate,migration,promote,promotion,imitate,imitation,decorate,decoration,confess,confession,express,expression,garbage,health,dirty,ocean,awful phsycial fitness and your __

asked by Neon on April 23, 2012
22. ## accounting -annual amount

The exhaust-gas temperature leaving a continuously operating furnace is 260°C, and a proposal is being considered to install a heat exchanger in the exhaust-gas stream to generate low-pressure steam at 105°C. the question to be investigate is whether it

asked by Alicia on November 18, 2010
23. ## accounting -annual amount

The exhaust-gas temperature leaving a continuously operating furnace is 260°C, and a proposal is being considered to install a heat exchanger in the exhaust-gas stream to generate low-pressure steam at 105°C. the question to be investigate is whether it

asked by Alicia on November 18, 2010
24. ## STOCKS & BONDS

The real risk-free rate of return has been estimated to be 2 percent under current economic conditions. The 30-day risk-free rate (annualized) is 5 percent. Twenty-year U.S. government bonds currently yield 8 percent. The yield on 20 year bonds issued by

asked by Yinka on November 15, 2012
25. ## Grammar

Rives the paragraph below to create shorter, more direct sentences. Years ago, when most of today's model railroaders were still growing up, the toy world offed a number of fantastic electric train sets that included engines with real steam and whistles

asked by Anonymous on March 5, 2013
26. ## English

Sorry, I forgot to change her into his. Was everything correct? Thank you. 1) First, Mrs Bennet informs her husband that a rich young bachelor, Mr. Bingley, has just rented the nearby estate of Netherfield and is going to take up residence (there) with

asked by Henry2 on December 18, 2011
27. ## math,algebra

I need help if someone can show me the steps to these 2 problems. Problem #1 Use the properties for radicals to simplify each of the following expressions. Assume that all variables represent positive real numbers. radical and inside of the radical theres

asked by jas20 on March 23, 2007
28. ## managerial economics

Exercise 1 The marketing manager has estimated the company’s demand curve with the equation P=3000 – 40Q. To develop a deeper understanding of pricing and quantity to be produced, complete the following analyses: 1. Draw the demand curve (use a range

asked by Butter on February 20, 2012
29. ## Biology organism classification

We have "made up" organism's based on real ones like these 2. Chemosynthetic goldfish that convert pollution to food (autotrophs) 3. Aquatic humanoids whose main diet is aqua-wheat and basking sharks. They have fins instead of legs (heterotrophs) 4.

asked by samatha on March 7, 2018
30. ## English

I have to write this poem for English. Can you please critique it for me? The Power of Time and Myself If I were to see me which is you Would you say that you're proud of what I've become. If I look into your eyes and told you things would be okay Would

asked by Arati on May 17, 2007
31. ## grammar

I have learned how to formulate personal learning goals SMART. Specific: a learning goal can only useful if it describes what you want to do; how you think, you will do it, when and where. A learning goal must be specific. During the class we must written

asked by hiop on December 20, 2011
32. ## Chemistry*Dr.Bob

I keep finding all sorts of different enthalpy of vaporizations for bromine. I used: 254.66 So factoring 254.66/2 into my equation below i ended up with a lattice energy of -863.33. Can you confirm this?

asked by Crystal on February 2, 2011
33. ## Economics

You are planning to estimate a short-run production function for your firm, and you have collected the following data on labor usage and output. Labor usage output 3 1 7 2 9 3 11 5 17 8 17 10 20 15 24 18 26 22 28 21 30 23 (a) Does a cubic equation appear

asked by Renee Williams on June 28, 2007
34. ## Animation

1. Music is shown to almost never evoke powerful emotions True False (My answer **) 2. Who pioneered the use of sound techniques that were developed from those used in radio dramas and meant to simulate real sounds? A)Thomas Edison (*** My Answer***)

asked by Ilovemusic on January 23, 2019
35. ## Cosmology

The solution of Olbers' Paradox is: - The universe is opaque at large scales - The universe expands - There is simply not enough starlight in the universe - Matter is clustered in such a way that the integral brightness converges

asked by qwerty on January 8, 2013
36. ## Chemistry

Iron -59 has a half life of 45.1 days. How old is an iron nail if the Fe-59 content is 25% that a new sample of iron? Show all calculations leading to a solution. Can you work the problem? I don't know how to solve for t!!! Please.

asked by noemi/ on May 11, 2015
37. ## Probability

4.3. In a certain college town, 27.5 percent of the students failed Mathematics (Math), 19.8 percent failed Biology (Bio), and 11 percent failed both Math and Bio. A student is selected at random. Let A represent the event of failing Math, so that A' is

asked by Carla Lopez on September 2, 2012
38. ## Macroeconomic

1)An example of an automatic stabilizer is A. a temporary tax rebate. B. the progressive income tax. C. cost of living adjustments to social security payments. 2)Which of the following represent expansionary fiscal policy? A. an increase in average

asked by Jill on June 9, 2010
39. ## Physics

PLEASE SOMEONE HELP ME WITH THIS DARN QUIZ. I'm so lost and all my teachers are too 'BUSY' to help me. :/ I'm getting so sick and tired of studying and not getting it but then having to take the blame for my instructor's folly. 2. Which of the following is

asked by Debbie on October 17, 2012

A kayaker paddled 2 hours with a 6 mph current in a river. The return trip against the same current took 3 hours. Find the speed the kayaker would make in still water. The speed is 6 mph slower going upstream and 6 mph faster going downstream. Distance

asked by Jessica on November 16, 2006
41. ## Macro

Real Disposable (Billions) Consumption Expenditures (Billions) Savings (Billions) Income \$100 \$150 ____________ 200 200 ____________ 300 250 ____________ 400 300 ____________ a. Graph the consumption function with consumption spending on the vertical axis

asked by Kay on April 16, 2013
42. ## Finance

On January 1, 2011 you bought a two-year U.S. government bond with a principal (face value) of \$1000 and a coupon rate of 6% with coupons paid on December 31, 2011 and December 31, 2012. The principal will be repaid on December 31, 2012. The Consumer Price

asked by Jerry on September 12, 2012
43. ## romeo and juliet

Hi. I have a question. Wasn't the play Romeo and Juliet by William Shakespeare based off of a poem by Arthur Brooke? This is what I was taught in school and have read on several websites, but someone else told me that what I know is completely wrong, but

asked by Savannah on April 4, 2007
44. ## Pre Calculas

7. For the function defined by: f(x)= {x^2, x1} a. evaluate f(0) 8. Solve the following system of equations algebraically. Verify your solution either graphically or by using matrices. 3x-y=0 5x+2y=22 9. Solve the following system of equations

asked by Ryan on October 6, 2015
45. ## English

I checked my mistakes. Can you please see if the sentences are possible? 1) First, Mrs Bennet informs her husband that a rich young bachelor, Mr. Bingley, has just rented the nearby estate of Netherfield and is going to take up residence (there) with some

asked by Henry2 on December 18, 2011
46. ## Math

1. Using the following system of equations : 4x +2x = 6 2x + y= 3 A: Find the solution(s) algebraically showing all work (4 pts) B: State whether it is independent consistent, dependent consistent, or inconsistent. (2pts) C: Demonstrate how to check the

47. ## CHEMISTRY

Find the equilibrium constant. 1. The equilibrium constant for the reaction,! Fe3+ + SCN- ⇋ FeSCN2+ (at a specific temperature), can be determined by first preparing a standard solution of FeSCN2+ and comparing its absorbance of light to an equilibrium

asked by Anonymous on December 3, 2013
48. ## English

I need a real life example of something that illustrates these qualities from "How to Read Literature Like a Professor?" by Thomas C. Foster I am doing a chapter from the book called Nice to Eat You: Acts of Vampires Basically this is what I got from the

asked by Annie on October 9, 2015
49. ## chemistry

briefly explain why excess HCl and NaOH solutions must be collected for treatment before disposal, but the titration solution from a completed titration can be safely poured into the drain, diluting with a large amount of water.

asked by Anonymous on March 23, 2011
50. ## Chemistry

excess magnesium is reacted with 45 grams of sulfuric acid. 9.5 liters of hydrogen gas are collected understand conditions of temperature and pressure. what is the percentage of hydrogen sulfate and of water in the acod solution?

asked by Anonymous on March 28, 2014
51. ## chemistry

10.2 g of Pb(NO3)2 are dissolved in 100 mL of water, and added to 250.0 mL of a 0.250 M solution of KI. Determine the mass in grams of Pbl2 produced, and find the number of moles of the excess reagent. PLZ explain

asked by Lisa on December 13, 2010
52. ## english

pls help in my research paper, i want to get your recommendations and comment as well as solution.. the title of my research is "causes why students are refraining from absences". now my problem is what is happen to the worldwide, national and local

asked by vanie on November 18, 2008
53. ## Chemistry: molality and freezing point?

What mass of ethylene glycol C2H6O2, the main component of antifreeze, must be added to 10.0 L water to produce a solution for use in a car's radiator that freezes at -23.3C? Assume the density for water is exactly 1g/mL. m = moles solute / kg solvent Help

asked by Agatha on January 27, 2009
54. ## chemistry

A dilute solution of sulfiric acid is added to 15g of copper and iron mixture. a) the volume of h2 envolved at standard conditions is 4.48L what is the mass of each of the metals constituting the mixture ? Vm=24l.mol.

asked by alaa on October 18, 2014
55. ## Chemistry

A solution of 0.200M NaOH (14.0 mL) is mixed with 42.4 mL of 0.170M HNO3. Assuming the final volume is the sum of the initial volumes, what is the molarity of Na+ cation and NO3- anion? I do not know where to start to solved for the molarity of the ions.

asked by Jessica on February 7, 2015
56. ## Chemistry

A 500.0-mL buffer solution is 0.100 M in HNO2 and 0.150 M in KNO2. Determine whether or not each of the following additions would exceed the capacity of the buffer to neutralize it. a. 250 mg NaOH b. 350 mg KOH c. 1.25 g HBr d. 1.35 g HI Can you explain to

asked by Johannie on October 31, 2010
57. ## chemistry

A solution prepared by adding 0.17 g of a polymer to 0.6 L of toluene (methylbenzene, a common solvent) showed an osmotic pressure of 0.808 Torr at 21â—¦C. What is the molar mass of the polymer? Answer in units of g/mol.

asked by Anonymous on November 27, 2017
58. ## chemistry

It is found that an average volume of 24.25 ml of approximately 0.1 M NaOH is required to reach an endpoint in a titration with 25.00ml of 0.09917 M HCl solution. What is the NaOH concentration? Make sure to give answer to four significant figures.

asked by mel on March 27, 2015
59. ## science

four flasks each contain 100 milliliters of aqueous solutions equal concentrations at 25 degress C and 1 atm. the four flasks are KCL,CH3OH, Ba(OH)2, and CH3COOH. the question is Which solution had the lowest freezing point and explain answer

asked by lisa on May 4, 2008
60. ## Analytical Chemistry

Given a 300 ml solution containing 0.2M H2L+ calculate the pH after the addition of 130.00 ml of 0.6M KOH. -----pH = 9.377 What total volume of KOH must be added to reach pH of 10.00 ---0.386 moles However, I am getting an amount of ml that is way too

asked by Jcc on March 12, 2015
61. ## Chemistry

I just wanted to clarify that although Cody did respond to my question, we were still unable to determine the solution. I will post a link to the question in a minute. (i noticed you replied to the other posts a bit ago, but i hope im not being too abrupt.

asked by Matt on November 20, 2011
62. ## chemistry

What is the boiling point of the solution in which you are going to cook spaghetti if it contains 51.0 g of NaCl dissolved in 1.30 L of water? Assume the density of water is 1.00 g/mL. Use molar masses with at least as many significant figures as the data

asked by jim on December 13, 2010
63. ## CHEMISTRY

Chromium plating is done using a dichromate solution. How long would it take to plate 1.0x10-2mm thick onto a car bumper with surface area 0.25m^2 in a 25.0 Amp electrolytic cell? (density of chromium is 7.19g/cm^3)

asked by PreMed33 on May 30, 2013
64. ## chemistry

the fictitious compound pandemonium carbonate has a ksg=3.091*10^-9 M 3 in water at poor temperature .calculate the solubility of PnCo3 in an aqueous solution of 1.11 M pandemonium sulfate. express your answer in units of molarity.

asked by himani. on May 5, 2013
65. ## Chemistry

Reviewing for final (this should be basic but...I am stuck): Describe how you would prepare 500.0 grams of a solution of sucrose, C12H22O11, in water which the mole fraction of sucrose is 0.125. I feel like somehow this is a molality question too :( Thank

asked by MiaowDescribe how you would prepare 1.00 on May 19, 2012
66. ## Science

What are the differences between these things? 1. substance vs. mixture 2. homogeneous vs. heterogeneous 3. solute vs. solvent 4. saturated vs. supersaturated 5. concentrated vs. dilute 6. element vs. compound 7. aqueous solution vs. universal solvent 8.

asked by Kaity on November 20, 2008
67. ## Organic Chemistry

Suppose a student started with 129 mg of trans-cinnamic acid and 0.50 mL of a 10% (v/v) bromime solution, and after the reaction and workup, ended up with 0.216 g of brominated product. Calculate the student\'s theoretical and percent yields.

asked by Need Help on August 10, 2012
68. ## Chemistry

Consider 57.5 mL of a solution of weak acid HA (Ka = 1.00 10-6), which has a pH of 3.800. What volume of water must be added to make the pH = 6.000? i made a ka for both of them to find out HA and i got .025M for fhte first one and 1E-6M for the second one

asked by Carry on February 26, 2009
69. ## Chemistry

Determine the volume of 0.250 M KOH solution required to neutralize each of the following samples of sulfuric acid. The neutralization reaction is: H2SO4(aq) + 2KOH(aq) = K2SO49aq) + 2H2O(l) Find: 205 mL of 0.130 M H2SO4

asked by Kelsey G on November 30, 2010
70. ## Chemistry

You are given a solution of HCOOH (formic acid) with an approximate concentration of 0.20 M and you will titrate with a 0.1105 M NaOH. If you add 20.00 mL of HCCOOH to the beaker before titrating, approximately what volume of NaOH will be required to reach

asked by Amber on November 11, 2015
71. ## Home, school and community

A teacher who makes a genuine effort to understand and solve problems that parents may have in a situation, but still finds no solution should: A. ask for the child to be moved to another class. B. remember that he or she is not alone. C. do exactly what

asked by farida on June 21, 2013
72. ## chemistry

Suppose a student started with 135 mg of trans-cinnamic acid and 0.52 mL of a 10% (v/v) bromime solution, and after the reaction and workup, ended up with 0.202 g of brominated product. Calculate the student's theoretical and percent yields.

asked by Anna on August 12, 2012
73. ## Physics I

Using 6400 km as the radius on Earth, calculate how high above Earth's surface you would have to be in order to weigh 1/16th of your current weight. Show all work leading to your answer OR describe your solution using 3-4 complete sentences.

asked by Sarah on October 28, 2014
74. ## bio

why does 10 % Sodium Chloride Solution affect and kill Sarcina lutea but not Serratia marcescens Escherchia coli Bacillus subtilus Bacillus cerus? I am trying to find some evidence of why but can't. It is true though because I tested it in a lab.

asked by rebekah on January 29, 2012
75. ## College Chemistry

Calculate pH of a 1.0 mol L -1 boric acid solution. (Ka(H3BO3) = 5.8 x 10 power -10 Please solve this problem. My computer does not have the power symbol. Can you please show maths and steps. Is mollar mass required of the above. Is -log and constant above

asked by Elleni on October 22, 2010
76. ## Chemistry

Using the balanced reaction, enter the formula, charge(if any), and state of the species (exclude H2O) in solution if Ba(NO3)2(aq) reactant is present in stoichiometric excess. Separate your answers by comma. NaCl(aq) + Ba(NO3)2(aq) → NR

asked by Kevin on January 29, 2010
77. ## Chem 2

So i need to calculate the pH of 50ml water (de-ionized) with 1 ml of 1M HCl. So the moles of HCl i think is .001 divided by the total amount of solution (.051). I get 0.0196, then i take the negative log of this number and it comes out to 1.71 roughly.

asked by Kyle on October 14, 2013
78. ## Chemistry

I've been stuck on this question for awhile now. I'm having a lot of trouble figuring out how to start it. If you had added exactly 20.00 mL do d.i. water before the titration, calculate the molar concentration of OAc- would have been at the end of the

asked by Rich on March 4, 2016
79. ## science

Calculate the pH of a solution of ammonium acetate (CH3COONH4) 0,85M knowing that for NH3 Kb = 1,79x10-5 and CH3COOH Ka = 1,76x10-5 and commented on the result obtained. Then calculate the percentage of acetic acid product at equilibrium

asked by frankscience on May 1, 2016
80. ## chemistry

If the unknown tri protic acid has an equivalent weight of 139.42 g/equiv, its average molecular weight is _________g/mol and __________g would be required to make 100.00 mL of a 1.50 N solution. See my response to your first question.

asked by jared on May 16, 2007
81. ## Chem

Tt is found that an average volume of 24.25 ml of approximately 0.1 M NaOH is required to reach an endpoint in a titration with 25.00ml of 0.09917 M HCl solution. What is the NaOH concentration? Make sure to give answer to four significant figures.

asked by Abenaa on May 3, 2013
82. ## Chemistry

A calorimeter contains 30.0 mL of water at 15.0 C. When 1.50 g of X (a substance with a molar mas of 46.0g/ mol is added, it dissolves via the reaction X (s) + H2O (l) ----> X (aq) and the temperature of the solution increases to 26.5 C. Calculate the

asked by Student on March 11, 2016
83. ## human services

In a essay i did on homeless i stated i feel police should be bring homeless to sfae sheltrers instead of writing them tickets for sleeping in a park. how can this solution be affected by social policies or government regulations? any one have any ideas

asked by jean on September 23, 2007
84. ## Acid/Base Chemistry

A 497 mL sample of 0.9960 M HI is mixed with 443 mL sample of KOH (which has a pH of 13.51). What is the pH of the resulting solution? What are the steps to solving this problem? I think you need to find the concentration of OH by taking 10^-pOH, and then

asked by Jenna on December 8, 2013
85. ## Mechanics

Typically, a tennis ball hit during a serve travels away at about 51 m/s. If the ball is at rest mid-air when struck, and it has a mass of 0.058 kg, what is the change in its momentum on leaving the racket? Show the solution and answer.

asked by Jason on September 19, 2013
86. ## Pharmaceutical Dosage Forms

If there is 1 g KH2PO4 and 1 g K2HPO4 in 100mL of solution, what is the mEq/mL of potassium? The Answer is 0.19mEq/mL. But I need to show work on how to get the answer. Textbook Applied physical pharmacy By Mansoor M. Amiji, Beverly J. Sandmann Chapter 3

asked by Jay on November 30, 2010
87. ## Math

A thin plastic band 50 cm long is used to tie seven plastic pipes together. What is the radius of the pipe? The shape is a hexagon but not vertices but curved. My solution was , you get an eqilateral triangle with side 3 r 3 r = 50/6 r = 50/6/3 = 2.73 But

asked by Manav on November 26, 2015
88. ## science

A solution of 0.200M NaOH (14.0 mL) is mixed with 42.4 mL of 0.170M HNO3. Assuming the final volume is the sum of the initial volumes, what is the molarity of Na+ cation and NO3- anion? I do not know where to start to solved for the molarity of the ions.

asked by Jessica on February 7, 2015
89. ## Chemistry

Suppose a student started with 133 mg of trans-cinnamic acid and 0.50 mL of a 10% (v/v) bromime solution, and after the reaction and workup, ended up with 0.236 g of brominated product. Calculate the student's theoretical and percent yields.

asked by Anonymous on January 23, 2013
90. ## trig HELP

A barn is 30ft. wide by 60ft long; the rafters make an angle of 40degrees with the horizontal. Find the area of each of the two gable ends and the area of the roof. Please Include Solution And If Possible An Illustration. Thank You In Advance :)

asked by Amber on July 5, 2012
91. ## AP Chemistry

So i had trouble finding the answers to these questions on a lab: Background: If we were using a burret/flask instead of a pipette and well plates. Before you started, the buret must be rinsed with 1 ml of distilled water and then 1 ml of NaOH solution.

asked by Ellan on October 1, 2009
92. ## English

Here are other sentences I need to check. I really hope you can check them, Writeacher. 1) blamed my friend Peter for breaking some plates, but the real guilty was me. I’m quite independent of my parents because I do a lot of things without their help.

asked by Matthew on April 20, 2012
93. ## Science

Hydrochloric acid and sodium hydroxide are mixed together to form salt and water. During the reaction, the temperature of the solution increases. Which of these best explains why this is considered to be a chemical change? No energy was destroyed. Heat was

asked by Anonymous on August 2, 2011
94. ## Physics (Classical Mechanics)

Hey.. I don't know exactly how to get the solution for this one... doubleudoubleudouble dot physikerboard.de/files/fahrzeug_223.jpg (its a sketch i made with paint^^) We assume there are no frictions at all and we only look at the masses M, m1 and m2. I

asked by Toby on November 18, 2010
95. ## history

the absence of effective action by congress on the question of domestic debt left the matter to be dealt with by the state governments. their solution was to a. do nothing b. raise taxes on property owners c. reduce tax rates in order to stimulate the

asked by kyle on September 14, 2008
96. ## College Algebra

Problem: Use Common or Natural Logarithims to solve the exponential equations symboliclly. 2e^7x+4=4 (Round to four decimal places) I tried solving this way 2e/2^7x+4=4/2 e^7x+4=2 ln e^7x+4=ln 2 7x+4=ln 2 7x+4-4=ln 2-4 7x=ln 2-4 7x/7=ln 2-4/7 x=ln 2-4/7

asked by Lee on November 14, 2010

What is the [H3O+] for a neutral solution at 50 degrees celsius? I know that kw=[H3O+][OH-] but I am not sure what to do to get the H3O. The value I have for kw=5.76e-14 and I have the pH 6.62 but I do not know what the OH would be.

asked by Hannah on March 31, 2012
98. ## math

how many oz of 25% alcohol solution must be mixed with 14oz of 30oz alcohol to make 26% alcohol

asked by nana on September 19, 2011
99. ## chemistry

What mass of PbCl2 would be found in 0.48 L of a saturated solution of PbCl2 if the Ksp of PbCl2 is 1.6 x 10-5?

asked by J.T on August 3, 2011
100. ## Algebra

A chemist has one solution of 20% acid and another of 50% acid. how many millimeters of each are needed to obtain 30 ml of 30% acid?

asked by TJ on March 13, 2015