# 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 677

Lifeguard Assignment Chris doesn’t like children, but he works as lifeguard at the Brigeland Community swimming. He does not like children a lot, but he is working as a lifeguard at the Brigeland Community swimming pool. He spends most of his time at the

asked by Sarah on May 22, 2013
2. ## algebra

Consider the following four polynomials, labeled A - D: A. ( 2x2 - 4x ) B. ( x3 - 1 ) C. ( -3x3 + x2 - 4x ) D. ( x5 + x2 - 3 ) Find an algebraic expression that uses each of the four polynomials once and simplifies to: x8 + 3 Your expression may involve

asked by Lilly on May 26, 2014

If someone can please help me i keep re reading my mathbook I need help i tried I'm unsure: Is there a relationship between area and perimeter? (My answer : yes they both are meadurements one reads the outside and one inside.) Does changing one mean the

asked by Angel on October 17, 2016
4. ## algebra

A disc jockey must play 14 commercial spots during one hour of radio show.Each commercial is either 30 seconds or 60 seconds long. If the total commercial time during 1 hour is 11 min, how many 30 second commercials were played that hour? How many

asked by babs on July 22, 2011
5. ## math

Charlie and Alexandra are running around a circular track with radius 60 meters. Charlie started at the western- most point of the track, and, at the same time, Alexandra started at the northernmost point. They both run counterclockwise. Alexandra runs at

asked by Rosalynn on August 10, 2011
6. ## math

LEGO R bricks are very common toys and have a structure that allows them to be placed on a rectangular grid. This makes them great for interesting questions about math. A 24 brick has two rows and four columns, making it have 8 total studs. But a 24 is

asked by al on November 10, 2014
7. ## Social Studies

One of the most hotly debated topics of national concern is gun control. In a complete essay, compose a proposal to either ban all hand guns or to allow free ownership of all hand guns and trace the history of this proposal. You must show the process it

asked by Tatianna on August 18, 2011
8. ## History

How can individuals promote tolerance and reduce prejudice in their towns and cities? One has to practice what one preaches is the first action. Secondly, one has to love and show love to those not like us. Respect and dignity are powerful forces. Thirdly,

asked by Melissa on January 5, 2007
9. ## algebra

Can someone show me how to set this up rational expressions. A pilot can travel 400 miles with the wind in the same amount of time as 336 miles against the wind. Find the speed of the wind if the pilot's speed in still air is 230 miles per hour.

asked by Anita on November 9, 2007
10. ## Math

Rafik counted the amount of money in his coin bank and wrote down the total. The amount was more than \$12 but less than \$13. The next day, he added a penny to the bank. To show the new total, he had to change exactly two digits in the old total. What are

asked by Wendy on October 30, 2012
11. ## PHYS

A bungee jumper (m = 61.00 kg) tied to a 45.00 m cord, leaps off a 75.00 m tall bridge. He falls to 5.00 m above the water before the bungee cord pulls him back up. What is the magnitude of the impulse exerted on the bungee jumper as the cord stretches?

asked by LEON on November 4, 2010
12. ## Quick ?

I doing a sample lesson plan for my english class. I want to show a movie that realtes to the book that were reading and the movie is 106 minutes. I teach each class for 50 minutes a day. How many days would it take to finish the movie and how long is 106

13. ## Math

The following data show the number of Chinese citizens who immigrated to the U.S. Use the data to predict how many Chinese immigrated to the U.S. during the 1990s. Decade No. of Chinese Immigrants 1950s 10,000 1960s 35,000 1970s 124,000 1980s 389,00

asked by Amy on March 29, 2011
14. ## math

The following data show the number of Chinese citizens who immigrated to the U.S. Use the data to predict how many Chinese immigrated to the U.S. during the 1990s. Decade No. of Chinese Immigrants 1950s 10,000 1960s 35,000 1970s 124,000 1980s 389,00

asked by Mick on March 29, 2011
15. ## Math

The following data show the number of Chinese citizens who immigrated to the U.S. Use the data to predict how many Chinese immigrated to the U.S. during the 1990s. Decade No. of Chinese Immigrants 1950s 10,000 1960s 35,000 1970s 124,000 1980s 389,00

asked by nancy on March 29, 2011
16. ## Science

Fill in the blank 1. _______ digestion occurs in the small intestine through the action of enzymes. 2. Urea, excess water, and other waste materials are eliminated in a water fluid called ___________. 3. __________ can cause infections by injecting DNA or

asked by Rose on November 19, 2018
17. ## SCIENCE

The tracks of the astronauts who landed on the moon are still there in the dust and show no signs of being worn away. This is attributed to the lack of atmosphere on the moon. Which of the following best accounts for the lack of atmosphere? 1)the moon's

asked by kayci on May 12, 2010
18. ## Science

The tracks of the astronauts who landed on the moon are still there in the dust and show no signs of being worn away. This is attruted to the lack of atmosphere on the moon. Which of the following best accounts for the lack of atmosphere. 1)the moon's weak

asked by Zay on May 4, 2016
19. ## chemistry

1. Heat can initiate reaction as well as be a product of chemical reactions. Cite the specific sample from the experiment that show heat acting in the manner 2. Aluminum chloride was a product in step 6. How could you instruct your lab partner to recover

asked by jhong on March 4, 2012
20. ## writing

about the 9/11 incident what major changes had taken place in America and had these changes been beneficical or non benefical??? In the last 5 years, some of the major changes have been: *preemptive war in Iraq *thousands of lives lost in Iraq *billions of

asked by bryan on August 27, 2006
21. ## statistics

The following table shows the summary statistic of the cholesterol levels of two groups of men in 2014. From 25 to 40 years old, the mean is 224, standard deviation is 5.5 and the sample size is 12. From 41 to 55 years old, the mean is 230, standard

asked by poon on November 15, 2014
22. ## physics

A thin spherical shell of mass 4.00 kg and diameter 0.200 m is filled with helium (density ρ = 0.180 kg/m3). It is then released from rest on the bottom of a pool of water that is 4.00 m deep. (a) Neglecting frictional effects, show that the shell rises

asked by teresa on January 26, 2012
23. ## Math

The Empire Carpet Company orders merchandise for \$14,486, including \$475 in shipping charges, from Mohawk Carpet Mills on May 4. Carpets valued at \$1,453 will be returned because they are damaged. The terms of sale are 2/10, n/30 ROG. The shipment arrives

asked by Joe Paul on December 7, 2014
24. ## statistics

When someone buys a ticket for an airline flight there is a 0.0995 probability that the person will not show up for the flight (based on data from the IBM research paper by Lawrence, Hong, and Cherrier). An agent for Air America want to book 24 persons on

asked by meagan on March 1, 2012
25. ## writing

Hello. I could really use some help with my ESSAY. If anyone could tell me what they think of it and if anything needs corrected. Thanks Jess Well I guess the best place to start is the beginning. I was born in Kentucky, but only lived there for five

asked by Jess on February 24, 2010
26. ## grammar

Hello. I could really use some help with my ESSAY. If anyone could tell me what they think of it and if anything needs corrected. Thanks Jess Well I guess the best place to start is the beginning. I was born in Kentucky, but only lived there for five

asked by Jess on February 23, 2010
27. ## physics

A spiral spring work with a piece of metal extent by 10.5 in arise when the metal is fully submerged in water,the spring extended by 6.8cm cal. the R.O of the metal (assumed hook's law is obeyed).

asked by Anonymous on March 11, 2019
28. ## physics

A wooden box is being pulled 10m from its original position along a horizontal surface by constant force of 25N calculate the work done on the box if the force is applied horizontally, and the force makes an angle of 37°.

asked by ann on August 19, 2015
29. ## Calculus II

A cone-shaped water reservoir is 20 ft. in diameter and 20 ft. deep. If the reservoir is filled to a depth of 10ft., then write the integral which represents the amount of work required to pump all the water to the TOP of the reservoir.

asked by RuggedChild on February 24, 2009
30. ## physics

A heat engine performs 272 J of work in each cycle while also delivering 241 J of heat to the cold reservoir. Find the efficiency of the heat engine. Give your answer in percent (%) and with 3 significant figures.

asked by Idali on April 6, 2017
31. ## Physics

A car travels at a speed of 25 m/s on a flat stretch of road. The driver must maitain pressure on the accelerator to keep the car moving at a constant speed. Are there any forces doing work on the car? Explain. What is the net force?

asked by Kourt on February 3, 2011
32. ## physics

A mechanic pushes a 2520 kg car from rest to a speed of v , doing 4310 J of work in the process. During this time, the car moves 22.4 m. Find the speed v . Neglect friction between car and road. Answer in units of m/s.

asked by allan on January 14, 2015
33. ## Chemistry

Person consumes 1995 Calories/day. How many is this in kJ My answer/work: 1995 x 1000 cal/1 Cal x 4.184J/1 cal x 1 kj/1000J= 8347.08kj Let me know if I did anything wrong and give me a hint on what I can do to fix it thank you :)

asked by Clare on January 26, 2015
34. ## calculus

Consider the solid obtained by rotating the region bounded by the given curves about the x-axis. y = 9 - 9x^2 , y = 0 Find the volume V of this solid. Sketch the region, the solid, and a typical disk or washer. Any help or tips would be greatly

asked by Tina on March 8, 2011
35. ## Physics

As shown in the figure below, a skateboarder starts at point A on the ramp and rises to point B, a maximum height of h = 2.89 m above the top of the ramp. If the amount of work done against friction is insignificant, determine his initial speed at point A.

asked by Anonymous on October 24, 2014
36. ## Physics

A baseball player hits a pop fly that goes directly up in the air with an initial velocity of 45 m/s. What is the maximum height the base ball reaches? Work: initial velocity = 45 m/s, gravity= -9.8 m/s, final velocity = 0 m/s

asked by Natascha on November 24, 2015
37. ## Physics

A 120 kg crate on the flatbed of a truck that is moving with an acceleration of 1.5 m/s^2 along the positive x axis. The crate does not slip with respect to the truck undergoes a displacement whose magnitude is 43 m. What is the total work done on the

asked by Amiel on March 18, 2015
38. ## algebra

Worker efficiency. In a study of worker efficiency at Wong Laboratories it was found that the number of components assembled per hour by the average worker t hours after starting work could be modeled by the formula N(t)=-3t+23t^2+8t

asked by Sandra on July 13, 2009
39. ## Physics - Help!

An incident light is monochromatic and of wavelenght 600nm, the kinetic energy of the electron is 2.56 x 10^(-20)J. For light of wavelenght 400nm, it is 1.92 x 10^(-19)J. Use the above information to estimate the value of Planck's constant,h and the work

asked by Sola on April 26, 2007
40. ## Physics

A car travels at a speed of 25 m/s on a flat stretch of road. The driver must maitain pressure on the accelerator to keep the car moving at a constant speed. Are there any forces doing work on the car? Explain. What is the net force?

asked by Kourt on February 3, 2011
41. ## Physics

In the following sentence, is the everyday or the scientific meaning of work intended? A student works on a term paper. The everyday meaning. The physical meaning would be measured in terms of the pushing of a pencil or keyboard keys.

asked by Anonymous on December 10, 2006
42. ## Physics

Consider the skateboarder in the figure below. If she has a mass of 57 kg, an initial velocity of 21 m/s, and a velocity of 10 m/s at the top of the ramp, what is the work done by friction on the skateboarder? Ignore the kinetic energy of the skateboard's

asked by Chrissy on October 17, 2014
43. ## Physics

A 200 kg wooden crate is dragged at a constant speed by a rope through a distance of 4 m along a wooden floor . The coefficient of sliding friction is .2 . If the work done is 1568 j , and the rope is horizontal, calculate the tension in the rope

asked by Lorna on March 1, 2012
44. ## Physics

A 200 kg wooden crate is dragged at a constant speed by a rope through a distance of 4 m along a wooden floor . The coefficient of sliding friction is .2 . If the work done is 1568 j , and the rope is horizontal, calculate the tension in the rope

asked by Lorna on March 1, 2012
45. ## Early Childhood Education

An activity center is an area where A. teachers conduct creative activites. B. children participate in active play. C. children and teachers plan the schedule for a day. D. children work on their own with little supervision. I think the answer is D but

asked by sarah on June 5, 2012
46. ## sir damon or any one help

two cars moves around a circle of circumference 20m with speed of 5m/s and 15m/s, if the positions of these cars are observed every integer seconds, after how many seconds will the cars occupy the same position. Plz maths work needed than

asked by putman/raj on January 19, 2017
47. ## Physics

A 200 kg wooden crate is dragged at a constant speed by a rope through a distance of 4 m along a wooden floor . The coefficient of sliding friction is .2 . If the work done is 1568 j , and the rope is horizontal, calculate the tension in the rope

asked by Lorna on March 1, 2012
48. ## PHYSICS

An applied force accelerates a 50-kg crate along a frictionless floor from rest to 5 m/s.The work performed by this force is most nearly 125 J 250 J(x) 500 J 625 J 1,250 J Can someone please explain this to me and help? I thought it was 250 J but my

asked by Chris on June 2, 2012
49. ## phyics

A mechanic pushes a(n) 3980 kg car from rest to a speed of v, doing 5107 J of work in the process. During this time, the car moves 29.3m. Neglect friction between car and road. Find the speed v. Answer in units of m/s.

asked by leslie on February 27, 2011
50. ## FIN

If a good friend of yours has had serious financial misfortunes lately and is unable to meet her debt payments, what advice can you give? Be sure to include the topic of bankruptcy because she has heard that it eliminates all your credit problems. In your

asked by Anonymous on June 12, 2006
51. ## Chem

Calculate the mass of PbCl2 formed when an excess of 0.100 M solution of NaCl is added to 0.4L of 0.7 M Pb(NO3)2. Pb(NO3)2 + 2 NaCl --> PbCl2 + 2 NaNO3

asked by DOnnie on May 18, 2014
52. ## math

jessie uses 20 liters of gasoline to travel 200 kilometers,how many liters of gasoline will he uses on trip of 700 kilometers?give the direct solution

asked by jenyrose loberanes on October 10, 2015
53. ## chemistry

A lactic acid/lactate ion buffer solution contains 0.43M HC3H5O3 and 0.90M C3H5O3-. The value of lactic acid is 1.4*10-4 calculate the pH of this buffer

asked by jennifer on June 16, 2015
54. ## Science

The vapor pressure of water at 25 oC is 23.8 torr. Calculate the vapor pressure of a solution prepared by dissolving 35.0 g of urea [(NH2)2CO] in 75.0 g of water at 25 oC.

asked by Carlos on February 17, 2013
55. ## chemistry

Calculate the solubility of barium iodate in a solution that results when 100 ml of 0.014 M barium chloride are mixed with 100 ml of 0.03 M potassium iodate.

asked by lakshmi on September 9, 2014
56. ## Algebra

Find the complete solution of each equation. Express your answer in degrees. sec^2 θ+sec θ=0 2 cos^2 θ+1=0 cot θ=cot^2 θ sin^2 θ+5 sin θ=0

asked by Lavanda on December 19, 2012
57. ## chemistry...

knowing that one mole of KHP, C8H5O4K, reacts with one mole of NaOH, what mass of KHP is required to neutralized 30.0mL of the 0.10 M NaOH solution?

asked by tierra on October 23, 2012
58. ## Chemistry

What is the hydrogen-ion concentration of a solution that is 0.016M in acetic acid and 0.016M in sodium acetate at 25 Celsius? The Ka for acetic acid is 1.8x10^-5

asked by Viv on March 22, 2013
59. ## Chemistry ASAP

the concentration of Ag+ in a saturated solution of Ag2Cro4 is 1.6x10^-4 M. what is the Ksp value for Ag2Cro4? the solubility of BaCO3(s) in water is 4.0X10^-5 M. Calculate the value of Ksp for BaCO3

asked by Anonymous on May 18, 2010
60. ## chemistry

the concentration of OH ions in a household ammonia cleaning solution is0.0035M. Calculate the concentration of H ions. would it be pH=-log (.0035)??? or Kc=1/.0035???

asked by david on April 10, 2008
61. ## Chem

a solution containing 100g of unknown liquid and 900g water has a freezing point pf -3.33 C. given kf=1.86 degrees c for water, the moelcular weight of the unknown liquid is what?

asked by Court on February 12, 2012
62. ## math

a teacher asks four students to write equations. the table shows the responses. student 1= 7x+x-8 = 2(4x-4) student 2= 6(x+2)+2x = 5x+2+8x student 3= 8x+x-5 = 9x+8 student 4= 6(2-x)+3 = -2(3x+2) which 2 students have an equation that has no solution A.1&2

asked by cxe on November 12, 2018
63. ## Chemistry

Which of the following solutions added to the hydrogen peroxide solution may act as a catalyst. KI, KCl, NaCl Are KI, KCl, NaCl all catalysts? But KI is more effective catalyst? Thanks.

asked by Sarah on March 2, 2010
64. ## chm

what is ph of a solution made by mixing 55ml of 0.12M in Formaic acid and 65ml of 0.12M of Sodium Foramte? For Ka of Formaic acid is 1.4x10^-4

asked by ami on June 27, 2010
65. ## Chemistry

What is the pH of a 0.1 M NaOCl solution (Ka of HOCl is 2.95 x10-8) I did: x squared/.10= 2.95x10-8 x squared= 2.95x10-9 x= 5.43x10-5 -log(5.43x10-5)= 4.27 pH However, the options I'm given are either a.) 3.74 b.) 6.47 c.) 8.23 d.) 10.27 What steps am I

asked by Marcus on April 8, 2013
66. ## Chemistry

How many moles of H2SO4 are needed to prepare 5.0 liters of 2.0M solution of H2SO4? a. 5.0 b. 10 c. 2.5 d. 20 Go back to the definition of molarity. M = #mols/L is the answer d If M = # mols/L, then L x M = #mols. 5.0L x 2.0M = 10 mols.

asked by Kat on March 26, 2007
67. ## Chemistry

How would you determine the concentration of H+, H2A and MB+ in a solution containing volumes of: H+ 600 microliters H2A 500 microliters MB+ 100 microliters H20 800 microliters

asked by Cristian on November 18, 2012
68. ## Biology

How would you prepare 100 ml of the following aqueous solution: 25 mM TrisCl, 50 mM EDTA, 2% (w/v) NaCl, 5 X M9? You have been provided with stock solutions of 1 M TrisCl, 0.5 M EDTA, 25 X M9 and crystals of NaCl.

69. ## math

so if a trapezoid has 4 sides and the top(short) side and the two not parallel sides are all 5 inches long, what are possible lengths for the long (bottom) side? and are there more than 1 possible solution?

asked by anna on March 22, 2016
70. ## Chemistry

In a similar experiment, a student needs a 0.50 M KOH solution (MM = 56.11 g/mol). The student only has a 50.00 mL volumetric flask. How much KOH should be added before the flask is filled with water?

asked by Lily on February 2, 2014
71. ## Algebra

Find the complete solution of each equation. Express your answer in degrees. sec^2 θ+sec θ=0 2 cos^2 θ+1=0 cot θ=cot^2 θ sin^2 θ+5 sin θ=0

asked by Lavanda on December 19, 2012
72. ## Chemistry

What is the freezing point of a solution prepared by adding 264g of copper(ii) sulfate to 4 liters of water? The freezing point constant of water is 1.86°C/m.

asked by Bruce Wayne on March 9, 2014
73. ## Pre Algebra

use the discriminant to determine whether the following equations have solutions that are: tow different rational solutions; two different irrational solutions; exactly one rational solution; or two different imaginary solutions. 25x^2=10x-1

asked by dianne on October 4, 2011
74. ## Chemistry

Which of the following solutions added to the hydrogen peroxide solution may act as a catalyst. KI, KCl, NaCl Are KI, KCl, NaCl all catalysts? But KI is more effective catalyst? Thanks.

asked by Sarah on March 2, 2010
75. ## Chemistry

A solution contains 25 mmol of H3PO4 and 10. mmol of NaH2PO4. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H3PO4 with NaOH?

asked by Holly on March 23, 2013
76. ## chemistry

190 grams of potassium iodide is placed in 100 cm3 at 60 degrees Celsius. the solution is cooled to 30 degrees Celsius. how many grams will settle out?

asked by Cara on September 19, 2013
77. ## Equilibrium constant

Consider the reaction: SO2Cl2(g)⇌SO2(g)+Cl2(g) A solution is made containing initial [SO2Cl2]= 0.022M . At equilibrium, [Cl2]= 1.7×10−2M Calculate the value of the equilibrium constant.

asked by Chemistry on May 5, 2015
78. ## MAth

All faces of a 4-inch cube have been painted. if the cube is cut into 1-inch smaller cubes, how many of them have no paint on all their faces? with solution pls... tnx...

asked by HELP HELP HELP MNHS on February 5, 2013
79. ## Chem

So I did a titration at school the other day and one of the questions is asking us to calculate the molarity of a solution but I don't know the # of moles of the solute. I know to calculate the molarity=# moles/ liters.

asked by Anonymous on January 25, 2014
80. ## chemistry

Which of these pairs of substances in aqueous solution would constitute a buffer? a. HCl + KCl b. KHPO4 + K2HPO4 c. KOH + KCl d. HCl + KOH

asked by anonymous on December 11, 2011
81. ## ap chemistry

For propanoic acid (HC3H5O2, Ka = 1.3 10-5), determine the concentration of all species present, the pH, and the percent dissociation of a 0.29 M solution. [H+] [C3H5O2-] [OH -] [HC3H5O2] pH percent dissociation

asked by Ryu on April 6, 2011
82. ## AP Chem

What is the freezing point in degrees Celsius of a solution prepared by dissolving 11.3 (g) of calcium nitrate in 115 (g) of water? K of f for water is 1.86 degrees Celsius/m

asked by Anonymous on January 22, 2013

Which of these pairs of substances in aqueous solution would constitute a buffer? a. HCl + KCl b. KHPO4 + K2HPO4 c. KOH + KCl d. HCl + KOH

asked by anonymous on December 12, 2011
84. ## chemistry pH

A 25 mL sample of 0.29 M LiOH analyte was titrated with 0.75 M HI at 25 degree Celsius. 1)Calculate the initial pH before any titrant was added. 2) Then calculate the pH of the solution after 5 mL of titrant was added.

asked by Mizuhara on October 13, 2014
85. ## Chemistry

A patient receves 3.0 mL of a solution containing technetium-99m for a breast image. If the activity of the technetium-99m is 9.5mCi/mL what is the dose received by the patient?

asked by Kayla on September 15, 2018
86. ## chemistry

sodium chloride has a molar mass of 58.4g/mole. how many grams of sodium chloride are needed to make 500.mL of a 0.0250 molar solution?

asked by alyssa on July 5, 2017

Calculate the concentration of HCO3- in an aqueous solution of 0.0885 M carbonic acid, H2CO3 (aq). I was going to set this up as 0.0885 -x = ? Am I suppose to use the Ka value for carbonic acid?

asked by Hannah on April 29, 2012
88. ## Math

cos x = -0.6 , 0

asked by Lester on November 7, 2014
89. ## math 7

All faces of a 4-inch cube have been painted. If the cube is cut into 1-inch smaller cubes, how many of them have no paint on all their faces? (With solution pls...) tnx

asked by MNHS_MNHS on January 13, 2014
90. ## math 7

All faces of a 4-inch cube have been painted. If the cube is cut into 1-inch smaller cubes, how many of them have no paint on all their faces? (With solution pls...) tnx

asked by MNHS_MNHS on January 13, 2014
91. ## Chemistry Lab

Suppose that you used 0.75g of iron. What is the minimum volume of 1.5 M_ CuSO4 solution required Using eqn. (3-1)? and eqn. (3-2)? (3-1) Fe(s) + Cu^2+ (aq) ---- Fe^2 (aq)+ Cu (s) (3-2) 2Fe(s)+ 3Cu^2+(aq) --- 2Fe^3+ (aq) +3Cu (s)

asked by Liza on September 12, 2015
92. ## ap biology

if you depress the plunger to the first stop, place the tip into a solution and then release the plunger, does it withdraw the sample, expel the sample, or eject the tip?

asked by Anonymous on September 15, 2015
93. ## Chemistry

How many grams of Na-benzoate (powder) do I need to prepare a buffer with pH = 4.2? How many grams of salt (NaCl) do I need to add to this buffer to make it a saturated solution of the salt? Thanks

asked by Ele on June 23, 2011
94. ## Chemistry

50.0mL of 0.200M HCl diluted to 100.0 mL and titrated with 0.200M NaOH. what is total volume of solution(L) if volume of NaOH added(mL) are 0.00, 5.00, and 10.0

asked by Anonymous on March 25, 2011
95. ## college chemistry

You have a solution that contains 12.0 g of NaCl in 50.0 g of water. Calculate the NaCl concentration in units of... mass percent and mole fraction would the mole fraction be 12/12+50=.1935

asked by i have half the question just need someone to chec on September 2, 2017
96. ## chemistry

Calculate the hydronium ion concentration and pH in a 0.037 M solution of sodium formate, NaHCO2. hydronium ion concentration i don't understand these

asked by sara on March 6, 2013
97. ## chemistry

How many grams of Pb(IO3)2(s) are precipitated when 27.0 mL of 3.00 M Pb(NO3)2(aq) are mixed with 30.0 mL of a 5.00 M KIO3(aq) solution? 3.00M(.o27)(1mol Pb(IO3)2)/1mol Pb(NO3)2)(557/1)

asked by jessie on November 11, 2014
98. ## Math 111

Use the discriminant to determine the number and type of solutions for the given equation. Either A, B, C, OR D 2x^2 = 7x - 8 A One (repeated) rational solution B Two irrational solutions C Two imaginary solutions D Two rational solutions

asked by Anonymous on April 2, 2010
99. ## chemistry

. How many grams of potassium chloride, KCl, are needed to prepare 0.630 L of a 2.50 M solution of potassium chloride? (4.0 points) (Points :4) 1.575 M 117 g 2.54 m 23.19 g

asked by Anonymous on May 24, 2010
100. ## Chemistry

what mass of precipitate will form if a saturated solution of potassium nitrate is dropped from a temperature of 70 degrees celsius to a temperature of 45 degrees celsius?

asked by Abby on May 18, 2015