# Questions Asked onOctober 11, 2010

1. ## Chemistry

Washing soda is a hydrate of sodium carbonate. Its formula is Na2CO3 X xH20. A 2.714 g sample of washing soda is heated until a constant mass of 1.006 of Na2CO3 is reached. What is x? What is the experimental mass percent of water in the hydrate?

2. ## chemistry

The boiling point of water at 735mmHg is 99.073C. What mass of NaCl should be added to 3.11kg water to increase the boiling point to 100.000C. Kb for water = 0.510K kg mol-1.

3. ## organic chem

organic chemistry lab and why is water the first choice for recrystallization when all factors are equal?

4. ## math

need the reponse for this y=x3 y=9-x3 y=y x^3=9-x^3

5. ## college

organic chemistry lab and why is water the first choice for recrystallization when all factors are equal?

x = 2 , 4 , 6 , 8 y = 18, 34, 50, 66 This is supposed to be a table where the x lines up with the y in order How would I find the equation to solve this when x = 20? x goes up by +2 y goes up by +16 but starts with 18

7. ## Algebra 2

How do you simplify (x^3+x^2-x-1)/(x^3-x^2-x+1)?

8. ## calculus

Suppose that the radius r of a right circular cone of fixed height h = 20 cm is increasing at a rate 4 cm/s. How fast is the volume increasing when r = 10? Give your answer correct to two decimal places.

9. ## Math

There are 2 hats, 3 scarves, and 3 pairs of mittens How many different combinations of 1 hat, 1 scarf, and 1 pair of mittens? How would I solve this, other than writing out each combination? Could someone please explain how?

10. ## English

What does it mean by Australia's success is riding on the sheep's back?

11. ## math

Number sence What is the number? It is greater than 43 and less than 52. If you add the digit, the sum is 8. write the number word. I need help figuring this out not just the answer but how to get the answer.

12. ## HEATHCARE

write a 1-2 page essay explaining how one of the following groups have addressed issues of cost control. healthcare, united states goverment and insurance

13. ## Chemistry

Consider the following reaction: CH4 +2O2 -> CO2 + 2H2O. Delta H = -891 kJ Calculate the enthalpy change for each of the following cases: a. 1.00 g methane is burned in excess oxygen b. 1.00 x 10^3 L methane gas at 740. torr and 25 *C is burned in excess

14. ## chemistry

Explain in words how you would prepare 250 ml of a 3.000 M solution of Ba(OH)2 starting from a two liter bottle of 12.000 M Ba(OH)2

15. ## Chemistry

Consider the combustion of propane: C3H8 + 5CO2 -> 3CO2 + 2H20. Delta H = -2221 kJ. What mass of propane must be burned to furnish this amount of energy assuming the heat transfer process is 60.% efficient?

16. ## maths

1+1= wat?

asked by justin beiber
17. ## chemistry

consider the following balanced chemical reaction: 2 Col3+3 K2S-> Co2S3+6 Kl assuming all that can react will react, how many grams of cobalt (III) sulfate will form when 1318.89 grams of cobalt (III) iodide are combined with 551.35 grams of potassium

18. ## composition and communication 1

i need to know how to write five sentences in which you address how your writing has changed in the first four weeks of class. the classis composition and communication 1

19. ## 2nd grade

What number am I My tens digit is double my ones digit. I am less than 70 greater than 60? How do u figure this out need help to explain how to get the answer..

20. ## Math

I need to divide 5/8 cup of buter into 12 servings

21. ## sociology

hi i would like to know if longitudinal study and participant observation is more or less the same thing??concerning their adv. n disadvantages???

22. ## chemistry

What is the energy of green light with a wavelength of 5.50x10^-7m?

23. ## Chemistry

In a car engine, gasoline (represented by C8H18) does not burn completely, and some CO forms along with CO2 and H2O. If 5 percent of the gasoline forms CO, A)What is the ratio of CO2 to CO molecules in the exhaust? B)What is the mass ratio of CO2 to CO?

24. ## English

The swimming strokes of the woman were jerky. Is this the correct verb to use in this sentence? The Subject is plural not so, so the verb must be plural too!

25. ## calculus

Find dy/dx 4x^2+y^2-8x+4y+4=0, find points on graph of the equation where there is a vertical or horizontal tangent line

26. ## Calculus

Inflection points of y= x/ x^2 + 25

27. ## calculus

c be the curve of the equation y=3x^5+10x^4-10x^3+60x^2+25x-5. among all points on the curve over the interval [-1,3], find the coordinates of the highest slope and lowest slope

28. ## Chemistry

Name some advantages of using acetaminophen instead of aspirin as an analgesic

asked by Mohammed kubaja
29. ## chemistry

how to dilute 7.75g of conc. HCl in 1000cm3?

30. ## physics

A 1-kg mass hangs by a string from a disk with radius 5.1 cm which has a rotational inertia of 5 × 10-5 kg•m2. After it falls a distance of 1.4 meters, how fast is it going? What is the angular velocity of the disk?

31. ## COM 156

Help with writing an outline on renting vs buying

32. ## Calc

find the cubic equation that has a y intercept of (0, -4) and has roots at x=1, x=2, and x= -5

33. ## social studies

Followed for one hundred years, one model for creating new territories was?

34. ## Math - Derivative of a polynomial function

A flaming arrow is shot into the air to mark the beginning of the a festival. Its height, h, in meters after t seconds can be modelled by the function h(t)=-4.9t^2+24.5t+2 How fast is the arrow traveling when it hits the ground? Explain how you arrived at

35. ## English

1. I am looking forward to my next visit there. 2. I am expecting my next visit there. 3. I am anticipating my next visit there. (Are they all the same and grammatical? What is the part of speech of 'there'?)

36. ## English

1. I was moved enough to want to help her. ( Is this grammatical?) 2. I was all wet after I washed only the first dog. (Does 'all' mean 'completely' here?) 3. Today was best. 4. Today was the best. (Which one is grammatical?)

37. ## English

1. At the end of the day, I was very tired but happy. (What is the opposite of 'at the end of'? Is it 'at the beginning of' or 'in the beginning of'?)

38. ## geometry

Two triangles are similar: the first has a base of 12 feet and a height of 16 feet; the second has a base of 9feet. What is the height of the second triangle?

39. ## GEOMETRY

Alicia is 5ft tall. she casts a shadow that measures 6 1/2 feet long at the same time that a sculpture in the park casts a shadow 12 ft long. which of the following is the approximate height of the sculpture? a) 2.0 miles b) 6.6 miles c) 12 miles d) 15.6

40. ## Happy Thanksgiving Canada

Happy Thanksgiving to my fellow Canadian tutors and to the Canadian students at Jiskha.

41. ## ENGLISH

What criteria do you suggest I make for my evaluation paper? My topic is that the school's celebratory bonfire for the basketball championship is a waste of time.

42. ## math

the coordinates of triangle KLM are K(-2,-5), L(0,1), M(6,-2) What type of triangle is KLM? A) obtuse isosceles B) acute scalene C) right isosceles D) right scalene

43. ## Math

A sequence of numbers is defined by the expression a(subscript n) = 3n + n^2 Which sequence corresponds to this expression? A)4, 9, 12, 20 B)4, 10, 18, 28 C)4, 10, 15, 20 D)5, 10 ,15 20 Question: What am I supposed to do here? How would I solve this?

44. ## intro to chemistry

The air in a 5.00L tank has a pressure of 1.20atm. What is the new pressure of the air when the air is placed in tanks that have the following volumes, if there is no change in temperature? A. 1.00L B. 2500ml C. 750ml

45. ## intro to chemistry

A sample of nitrogen has a volume of 50.0L at a pressure of 760mmHg. What is the volume of the gas at each of the following pressures if there is no change in temperature? A. 1500mmHg B. 2.0atm C. 0.500atm

46. ## math

when a marble hits a wall at a 22 degree angle, what is the measure of the angle between the two paths of the marble?

47. ## Physics

To store the energy produced in 1.5 hour by a 160 MW (160 10^6 W) electric-power plant, how many cubic meters of water will have to be pumped from the lower to the upper reservoir? Assume the upper reservoir is 500 m above the lower and we can neglect the

48. ## math

marcias house is approx. 10 miles east of the airport. a jet is flying directly over her house after taking off from the airport and flying approx. 12 miles. approx how many miles high is the jet when it flys over marcias house?

49. ## Math

x = 2 , 4 , 6 , 8 y = 18, 34, 50, 66 This is supposed to be a table where the x lines up with the y in order How would I find the equation to solve this when x = 20? x goes up by +2 y goes up by +16 but starts with 18 I already posted this and got the

50. ## geometry

A manufacturer wants to make a rectangular storage box with volume 0.75 cubic meters, length 1.5 meters and width 0.4 meters. What is the height of the box?

51. ## math

Erica took 2 days to drive 1,020 miles. On the first day she drove 10 hours at an average spped of 62 mile per hour. on the second day, her average spped was 57 miles per hour. approx. how long did she drive on the 2nd day?

52. ## organic chem

7. An unknown compound, C8H14, is optically active. Hydrogenation of the unknown yields 4-methylheptane. Ozonolysis of the unknown yields ethanol and 2- methylpropandial. Suggest a structure for the unknown consistent with the above date. please help

53. ## differentiation

Find y''(x) if y=(x)^1/2 tan (x)^1/2

54. ## diploma in pre school

Hi, can u pls check the english i used in my assigment is correct? if not pls correct and tell me where is my weekness. T/C INITIAL - K T/C SEX - Male T/C AGE - 3.8 yrs SETTING - Painting area & Jigsaw table area. PEOPLE - 1 Targeted child T/C - 3

55. ## math

how do yu find the implicit differentiation for this porblem 4cosx*siny=1

56. ## chemistry help

enzymes and substrates overall reaction: S -> P step 1: E + S -> ES fast step 2: ES -> E + S fast step 3: ES -> E + P slow what is the order of the reaction in E and what is the order of reaction in S?

57. ## English

Can you please check if everything is correct? 1) The last decades of the 18th century were characterized by enormous changes, (witnessed enormous changes?) which turned Britain from a mainly farming country toan industrial one. 2)In particular, there was

58. ## physics

A 0.80-kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 1.7 m on a frictionless horizontal surface.If the cord will break when the tension in it exceeds 90 N, what is the maximum speed the ball can have? Express your

59. ## math

a group of 25 students, 17 have socks on their feet, 12 have shoes on their feet, and 9 have both socks and shoes on their feet. how many students are barefoot

60. ## Calculus

Consider the region bounded by the curves y=e^x, y=-e^x, and x=1. Use the method of cylindrical shells to find the volume of the solid obtained by rotating this region about the y-axis.

61. ## Chemistry

How many grams of sucrose (C12H22O11) must be dissolved in 200 g water to make a solution in which the mole fraction of sucrose is 0.2? Answer in units of g.

62. ## Chemistry

Calculate the molality of CsCl in a 18% by mass aqueous solution. Answer in units of m.

63. ## Chemistry

When 0.016 moles of lead(II) nitrate are dissolved in enough water to make 748 mililiters of solution, what is the molar concentration of nitrate ions? Answer in units of M.

64. ## Chemistry

What mass of MgSO4 · 7H2O is required to prepare 800 mL of a 0.442MMgSO4 solution? Answer in units of g.

65. ## math

f(x) = x+3 if x < equal to -3 4 if x > -3 1. lim x-> -3 from the left 2. lim x-> -3 from the right I need a specific point for each limit.

asked by Marshall Mathers
66. ## math

what is the horizontal limits of : (10x^3-11x^2-2x)/(7-8x^3)

asked by Marshall Mathers
67. ## REACTION STEPS AND MECHANISM FOR [CO(NH4)3CO3]NO3

(NH4)2CO3 + NH3+[CO(OH2)6](NO3)2+H2O2

68. ## MATH

How can you determine if two lines are perpendicular? · How the slopes of two perpendicular lines relate; · How you recognize if two lines are perpendicular on a graph; · How you recognize if two lines are perpendicular simply from their equations.

69. ## physics

A sports car of mass 950 kg (including the driver) crosses the rounded top of a hill (r = 88 m) at 27 m/s. Determine the normal force exerted by the road on the car. Determine the normal force exerted by the car on the 72-kg driver. Express your answer

70. ## health

how does socioeconomics and educational opportunity are main reason for health disparities?

71. ## math

what is the domain of this function in interval form: 1/(5x^3-6x)

asked by Marshall Mathers
72. ## Chemistry

HNO3+NaOH --- H2O+NaNO3 What is formed in the solution besides Cu(OH)2?

73. ## To Canadiens

Happy Thanksgiving/ un heureux jour de l'action de grâce.

q:what kind of economic system does france have? a:france has a mixed economy q:Does France import more than they export or export more than they import? a:export more than they import q:Is france part of a large economic system? a:yes. are these answers

75. ## earth space science

A substance that cannot be broken down into simpler substances by physical or chemical needs is called an

76. ## 11th grade

When the shuttle bus comes to a sudden stop to avoid hitting a dog, it decelerates uniformly at 5.3 m/s2 as it slows from 9.5 m/s to 0 m/s. Find the time interval of acceleration for the bus. Answer in units of s

77. ## physics

A car traveling at 7.3 m/s accelerates 4.5 m/s2 to reach a speed of 11.0 m/s. How long does it take for this acceleration to occur? Answer in units of s.

78. ## physics

as a hiker descends a hill, the work done by gravity on the hiker is a.) positive and depends on the path taken b.) negative and depends on the path taken c) positive and indepedent of the path taken d.)negative and independent of the path taken

79. ## physics

If a loaded truck that can accelerate at 1 m/s2 loses its load and has four-fifths of its original mass, what acceleration can it attain if the same driving force acts on it?

80. ## Math/English?

Hey! How's it going? Can anyone help me out here? My teacher asked us students to come up with a mnemonic device for PEMDAS (you know, the order of Operations), other than Please Exuse My Dear Aunt Sally. I came up with great ideas, but she changed her

81. ## Health Information

Dr. Bob's computerized records are damaged by a power surge. Which of the following is most true? A. Dr bob isn't at fault. B. Dr Bob is at fault. C. The records custodian, but not Dr bob will be liable. D. Dr Bob is at fault unless he had proper surge

82. ## biology

Hello, I was just wondering what the difference between anatomical and physiological. I'm reading a reserach paper that talks about how light levels 'involve both physiological and anatomical changes to the leaves.' I don't know what the difference between

83. ## Limits

F(x)= 11 if x > 10 4 if x = 10 -x+11 if 0 < equal x < 10 11 if x 10 from the left 2. lim x-> 10 from the right 3.lim x-> 0 from the left 4. lim x-> 0 from the right 5. lim x-> 0

asked by Marshall Mathers
84. ## MATH

Post your 50 or more word response to the following in the assignment link: How can you determine if two lines are perpendicular? Your response should include the following: · How the slopes of two perpendicular lines relate; · How you recognize if two

France is an independent nation in Western Europe and the center of a large overseas administration. It is the third-largest European nation (after Russia and Ukraine). In ancient times France was part of the Celtic territory known as Gaul or Gallia. Its

86. ## physics

What force is needed to accelerate a child on a sled (total mass = 65.0 kg) at 1.75 m/s^2

87. ## Physics

A mine shaft is known to be 57.8 m deep. If you would drop a rock down the shaft, how long would it take for you to hear the sound of the rock hitting the bottom of the shaft knowing that sound travels at a constant velocity of 345 m/s? The answer is

88. ## us history

Distinguish between "older culture" and "new culture" present in 18th century colonial America, and discuss the value conflict that emerged between the two.

89. ## physics

A hypothetical planet has a radius 1.1 times that of Earth, but has the same mass. What is the acceleration due to gravity near its surface? Express your answer using two significant figures.

90. ## Chemistry

Balance? Cr2O7^2- + C2H4O yields C2H4O2 + Cr^3+ (When I say ^ a number followed by a plus or minus that's the charge) Half-reaction method needed.

91. ## Physics

What average force is required to stop an 1600 -kg car in 8.0 s if the car is traveling at 80 km/h?

92. ## Physics

What average force is needed to accelerate a 8.00-gram pellet from rest to 135 m/s over a distance of 0.800 m along the barrel of a rifle?

93. ## PHYSICS ---HELP!

The space shuttle releases a satellite into a circular orbit 700 km above the Earth. How fast must the shuttle be moving (relative to Earth) when the release occurs?

94. ## chemistry

The weight of an atom is made up of what? protons and electrons neutrons protons electrons neutrons protons electrons and neutrons

asked by kaiya english
95. ## Chemistry

Assignment  Calculate the pH, pOH, [H+], and [OH] for each of the following solutions. Show all work. (10 Points) Solution Composition of Starting Materials 1 0.10 M acetic acid 2. 5 mL 0.10 M acetic acid + 5 mL wa 3 1 mL 0.10 M acetic acid + 99 mL

96. ## Intermediate Algebra (Math)

HELP PLEASE, Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. -2x Ð 8y = 22 -6x Ð y = 20 At first I tried to multiply by 8 but that did not work.

97. ## Intermediate Algebra

Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. -7x Ð 5y = 1.5 -5x Ð 4y = 4.5

98. ## Algebra (Intermediate)

Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. 9x + 6y = 60 -27x Ð 18y = -180

99. ## Intermediate Algebra

Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this. -3x + y = 4 x + 3y = 22 Here's what I came up with (where did I go wrong) -3x + y = 4 y = 4 - 3x -3x + (4-3x) = 4 -3x + 1x =

100. ## algebra I

What is 3/4x-7=8+-6x

228. ## Chemistry

The electrolysis (decomposition) of water produces hydrogen gas at the rate of 30.0 mL/min. A) Write a balanced chemical equation for this reaction and include phase designations. 2H2O(aq)---> 4H2(g)O2(g) Is whatever I've done above correct? B) What volume

229. ## physics

Three identical masses of 500 kg each are placed on the x axis. One mass is at x_1 = -11.0 cm, one is at the origin, and one is at x_2 = 37.0 cm. What is the magnitude of the net gravitational force F_grav on the mass at the origin due to the other two

230. ## Physics

Deaths associated with lightning in South Africa are about four times higher than the global average. A typical thundercloud maybe at a potential of 1,2 times 10^8V and the thunder strike may result in a charge transfer of 20C. CALCULATE THE CURRENT

231. ## Physics

A golfer imparts a speed of 32.1 m/s to a ball, and it travels the maximum possible distance before landing on the green. The tee and the green are at the same elevation. (a) How much time does the ball spend in the air? (b) What is the longest "hole in

232. ## environmental science

A farmer planted a fiel od BT-123 corn and wants to estimate the yeild in terms of bushels per acre. He counts 22 ears in 1/1000 of an acre. He determines that each ear has about 700 kernels on average. He also knows that a bushel contains about 90000

233. ## Science

If you thought you had discovered a new element, how could you get the scientific world to accept your discovery? What roadblocks might you face, working outside the science community? How could you avoid being labeled a "crackpot"?

234. ## Chemistry

Name four factors that can affect the rate of a chemical reaction. How does the rate of a chemical reaction change in response to a change in each factor? My answer: Four factors that can affect the rate of a chemical reaction are concentration, surface

6d-3d+2d=35?

236. ## Social Studies

Name 3 things that the Maya developed.... 1-their own writing system 2-their own counting system (including zero) 3-built 100 stone cities Is #3 correct? I can't find anything else!

asked by I'm horrible
237. ## EDU

How many children are educated in pk 12 public schools in the united states?

238. ## ap chem

A 1.42 g. sample of a pure compound, with formula M2SO4, was dissolved in water and treated with and excess of aqueous barium chloride, resulting in the precipitation of all the sulfate ions as barium sulfate. The precipitate was collected, dried, and

asked by josh sears
239. ## physics

A 200g mass is connected by a string to a large mass which is accelerating to the right at 2m/s2. What angle, θ, does the string make from vertical? What would the angle be if the acceleration to the right was 9.8m/s2? [Hint: Focus just on the ball. And

240. ## Physics

Michael Jordan, formerly of the Chicago Bulls basketball team, has some fanatic fans. They claim that he is able to jump and remain in the air for two full seconds from launch to landing. Evaluate this claim by calculating the maximum height that such a

241. ## spanish

Isabel una chica norteamericana uses of the ver ser

242. ## economics

What is the relationship between GDP and the business cycle? How can you use information about the business cycle when making a decision about a large purchase?

243. ## Math

Step 1 = 3 boxes Step 2 = 6 boxes Step 3 = 11 boxes Step 4 = 18 boxes How many boxes at step 50? Which one? 100, 102, 2500, 2502 How would I solve this?

244. ## math HELP

A baker used 16 pounds of flour and 12 cups of sugar to make several batches of cookies. the baker used the same amount of flour and sugar in each batch of cookies. what is the number of batches the baker could have made with his flour and sugar? this is

245. ## PHYSICS ---HELP!

The space shuttle releases a satellite into a circular orbit 700 km above the Earth. How fast must the shuttle be moving (relative to Earth) when the release occurs?

246. ## Chemistry

What is the fundamental premise of the collision theory? My answer: The fundamental premise of the collision theory is that in order for moving particles to react, they must first collide with a certain minimum amount of energy. Is my answer right?

10x+7+3x

248. ## Chemistry

Describe two features of a catalyst: -used in the industrial manufacture of chemicals where the rate of production is important. -assists reactants in their collisions but remains unchanged at the end of the reaction. Is this what they mean by "Give two

249. ## Physics

A child slides down a hill on a toboggan with an acceleration of 1.5 m/s squared. If she starts at rest, how far has she traveled in 1.0 s, 2.0 s, and 3.0 s?

250. ## Science

The state of cellular equilibrium is best described as a dynamic condition, not static. What does this mean?

251. ## 6th grade - EARTH SCIENCE

What are three interesting facts about the upper mantle of the earth? and 3 interesting facts about the lower mantle of the earth?

20u-6(u+5)

p-5(2-3)+1

254. ## Chemistry

A total of 2.00 mol of a compound is allowed to react in a foam coffee cup that contains 141 g of water. The reaction caused the temperature of the water to rise from 21.0 to 24.7 degrees Celsius. What is the enthalpy of this reaction? Assume that no heat

255. ## algebra

How do I solve problems similar to: 2/3X - 1/2Y = 3

256. ## 8th grade

Data plotted on a graph results in a line that slopes upward from left to right. This graph tells you that a)when one variable increases, the other variable decreases. or b) when one variable increases, the other variable increases?

257. ## Math

Please help!!!! Solve each system graphically. Be sure to check your solution. If a system has an infinite number of solutions, use set-builder notation to write the solution set. If a system has no solution, state this. 6x - 2y = 2, 9x - 3y = 1 My answer:

-2(2m-1)+4m

259. ## Physics Help!!

Three identical masses of 500 kg each are placed on the x axis. One mass is at x_1 = -11.0 cm, one is at the origin, and one is at x_2 = 37.0 cm. What is the magnitude of the net gravitational force F_grav on the mass at the origin due to the other two

260. ## English

1. What did Bora want to do? - She wanted to do volunteer work. 2. Where do her friends usually volunteer? - They usually volunteer at libraries or town halls. 3. Did Bora want to volunteer at a library or a town hall? - No, she didn't. 4. Who told Bora

261. ## math

3x-5x=

asked by shantel brown
262. ## English

1. He wants to do two kinds of volunteer work this month. 2. He wants to do two volunteer works. (Are they correct?)

263. ## Com/155

This week, you were asked to review the Topic Sentence section in the Center for Writing Excellence. Using the topic of home ownership versus leasing, identify a topic and provide a topic sentence you would use in a paragraph about the topic.

264. ## math

b-9b??? how are you supposed to simplify if there isnt a nmber before the b????

265. ## Physics

On vacation, your 1300 kg car pulls a 540 kg trailer away from a stop light with an acceleration of 2.02 m/s2. (a) What is the net force exerted by the car on the trailer? (b) What force does the trailer exert on the car? (c) What is the net force acting

266. ## edu310

what role do colleges and universities play in preparing future educators to be successful in the classroom

267. ## Math

If I had to find the area of a circle (3.14)r^(2) - and it states that it is 5 meters in diameter would I divide 5 by 2 = 2.5 and then multiply 2.5 by 2.5 to get 6.25?

268. ## algebra 2

find the gcf and lcm of 315 and 882.

269. ## physics

A spacecraft is traveling with a velocity of v0x = 6370 m/s along the +x direction. Two engines are turned on for a time of 843 s. One engine gives the spacecraft an acceleration in the +x direction of ax = 1.20 m/s2, while the other gives it an

270. ## chemistry

A solution contains an unknown amount of dissolved magnesium (Mg 2+). Addition of 5.50×10^−2 mol of Na2CO3 causes complete precipitation of all of the magnesium. what mass of the magnesium was dissolved in the solution? answer in unit g.

271. ## algebra 2

find the gcf and lcm of 315 and 882.

272. ## Where is DrBob222?

Hey does anyone know when DrBob222 comes on here, cause I have a lot of chemistry questions which I need him to check. Thanks.

273. ## Chem

Calculate the work done when 40.0 g of tin dissolves in excess acid at 1.00 atm and 29°C. Assume ideal gas behavior. Sn(s) + 2 H+(aq) → Sn2+(aq) + H2(g)

274. ## English

What are some frequently misused adjectives?

275. ## Math

-4=x/7+3 i need to find the answer for "x"

276. ## English 2

Which hero's story, King Arthur's or Sundiata's, has the more relevant message for young people today? Compose an essay that answers this question, giving at least two examples from the selections and applying them to issues young people face today. Need

277. ## 6th grade math

Add one set of parentheses to the expression - 7 * x + 3 + 8 * x + 3 * x + 8 - 9 so that it is equivalent to 2(9x + 10)

278. ## Ecology

I have to determine what color topsoil is most fertile. I'm not sure if it would be dark brown (because it reflects a lot of broken down organic material) or red (because it's clay, and clay is good for agriculture). What do you think?

279. ## Math

What are the vertical and horizontal stretch/compressions for the functions h(x)=1/(5x) and k(x)=|0.4x| ?

280. ## English

I needed to create sentence containing the phrase "green with envy". I have got two sentences here, but I need help picking out the one that makes more sense. Emily’s new look made her friends green with envy. Emily’s friends became green with envy

281. ## science

an airplane normally flies at 200 km/h, what is the resultant velocity of the plane if it experiences a 50 km/h tail wind, and a 50km/h head wind

282. ## ap chemistry

A titration. 12.46 mL of KMnO4 are titrated with 25 mL of H2C2O4. The half reaction is 2H2O+H2C2O4 ARROW 2H2CO3+2H+2e-. How do I get the molarity of H2C2O4? PLEASE HELP

283. ## English

What would be good sentence for emerald?

304. ## Economics

who knows how to measure the true cost of a pint of B-Positive blood? A.None of these B.Any competent medical authority C.Only the Surgeon General of the United States D.An economist E.A clerk at the blood bank

305. ## Statistics

Hi, My professor gave us the formulas for sample variance and population variance, as well as the shortcut formulas for each. However, he said that on some of the problems, we will HAVE to use the long formula, which for population variance would be:

306. ## physics

A golfer imparts a speed of 32.1 m/s to a ball, and it travels the maximum possible distance before landing on the green. The tee and the green are at the same elevation. (a) How much time does the ball spend in the air? (b) What is the longest "hole in

307. ## calculus 1

Find d/dx for (sin πx + cos πy)4 = 65

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308. ## Chmistry

A sample of copper with a mass of 63.5g contains 6.02x10^23atoms.Calculate the mass of a single copper atom.

309. ## Math

Write a two column proof. -If XZ=ZY,XZ=4x+1,and ZY=6x-13, then x=7. Statements: Reason: 1.XZ=ZY,XZ=4x+1 and ZY=6x-13 1.Given That as far as I got to ^. Thanks

310. ## algebra

25 miles / hour = x meters / minute

311. ## calculus

Please help, thank you!!! Find the derivative of the function. g(θ) = (cos(8θ))9

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312. ## chemistry

If a reaction mixture contains 28 of , 150 of , and 36 of , what is the limiting reactant?

313. ## Chemistry

20.5 mL of oxalic acid,H2C2O4 were titrated with 0.800 M solution of lithium hydroxide. It took 40.0 mL of the base to reach the equivalence point. What is the molarity of the oxalic acid?

314. ## physics

There is a heat flow through a block of cross sectional area 21.5 cm2 and length 39 cm when the temperature difference of 18 degree Celsius is established across the block. Find the rate of heat flow through the block, assuming it is made of aluminium with

315. ## Intro to Economics

Past expenses are irrelevant to decisions to supply now, because A.people forget the past quickly B.it is esssential to avoid bankruptcy C.supply decisions depend on opportunities thst will have to be forgone, not opportunities already forgone D.expenses

316. ## math

if a child and adult paid $23 for 2 tickets and an adult ticket is$6.50 more than the childs ticket, how do i get the answer?

317. ## mgt 307

Members of __________ must have good long-term working relationships with one another, solid operating systems, and the external support needed to achieve effectiveness over a sustained period of time.

318. ## physics

Tarzan, who weighs 780 N, swings from a cliff at the end of a 12.0 m vine that hangs from a high tree limb and initially makes an angle of 49.0° with the vertical. Assume that an x axis extends horizontally away from the cliff edge and a y axis extends

319. ## ap chem

Hydrogen cyanide is produced industrially from the reaction of gaseous ammonia, oxygen and methane: 2NH3(g) + 3O2(g) + 2CH4 -->2HCN + 6H2O(g) a)If 5.00 x 10^3 kg each of NH3 , O2, and CH4 are reacted what mass of HCN will be produced, assuming 100% yield?

320. ## physics

A spring is launched at and angle of 30 degrees and pulled 30 cm back.The distance from the floor to the top of the launcher is 35 cm. At what distance will the spring lan in the bucket?

321. ## Chemistry

Calculate the work done when 40.0 g of tin dissolves in excess acid at 1.00 atm and 29°C. Assume ideal gas behavior. Sn(s) + 2 H+(aq) → Sn2+(aq) + H2(g)

322. ## chemistry

DNA is approximately 2.5 nm in length. If an average man is 6 feet tall, how many DNA molecules could be stacked end to end in an average man?

323. ## chemistry

A liquid has a volume of 3.70 liters. What is its volume in mL? In cm cubed?

324. ## chemistry

A solution contains 0.245 of dissolved lead (lead ion or Pb2+.) How many moles of sodium chloride must be added to the solution to completely precipitate all of the dissolved lead? What mass of sodium chloride must be added?

325. ## physics

A object is throw up with a speed of 25m/s. suppose that the gravity is 10m/s^2. Define the position and the velocity of the particle for the following times: 1second, 4second and 10second

326. ## physics

A stone is thrown vertically upward with a speed of 11.5 m/s from the edge of a cliff 95.0 m high. (a) How much later does it reach the bottom of the cliff? (b) What is its speed just before hitting? (c) What total distance did it travel? For (c), the

327. ## English

1. They are eating cotton candy. 2. They are eating cotton candies. 3. They are eating a cotton candy. 4. The boy is eating two cotton candies. (Which one is correct?)

328. ## chemistry

How do you calculate Ke for 2 SO2 (g) + O2 (g) ↔ 2 SO3 (g) + heat [0.0500] [0.0500] [0.103]

329. ## INTRO TO ECO

Opportunity-cost theory suggests that the cost to an airline of letting its employees fly at no charge... A.is greater around the Christmas holidays B.will depend upon the value employees place upon travel C.zero D.depends upon alternatives avaliable to

330. ## math

AMy's kite flew the highest. Benny's kite flew 50ft lower then amy's but 100 feet higher then cathy's. Cathy's kite was 100 feet higher then Devons. Devons' kite was 300 feet above the ground. How high was Amy's kite?

331. ## Science

A 65 kg woman dives from a 10 m platform. What is her speed as she enters the water.

332. ## Math

margarit liked to balance things. she balanced 3 pencil sharpeners and 2 one gram blocks with a 100 gram weight and another one gram block. she let x stand for the weight of one pencil sharpener and she claimed that x=30grams. was she correct if not how

333. ## economics

if land suitable for growing corn is also suitable for growing soybeans, the discovery that soybean oil prevents cancer will A.have no effect on the cost of growing corn B.reduce the cost of growing corn C.raise the cost of growing corn D.decrease the

334. ## History

What are 3 factors that made Congress pass the Immigration Act of 1924? - racism can't think of the other two.

335. ## 8th grade math

is n^2-3 a monomial

336. ## 8th grade

What does "Le gusta aprender el espanol a ella?" Mean?

337. ## English

1. I usually go fising on weekend. 2. I usually go fising on weekends. (Are both right? 'On weekends' mean 'every weekend', I know. What is the difference between #1 and #2?)

338. ## math

show 14 broken key is 1 show 2 ways

339. ## Intro to ECONOMICS

the basic reason suburban stores are more likely than downtown stores to provide free parking for their customers is that.. the cost of using land is higher in the downtown area?

340. ## English

1. Dr. White helped many people. (In this sentence, is "Dr. White" a doctor?)

341. ## English

1. The volunteers there deliver food to old people. (What is the part of speech of 'there'? Does 'there' modify 'volunteers? Then it is an adjective? Or is 'there' an adverb?)

342. ## 5th grade math

How can knowing the multiplication. Properties help you evaluate five times twenty times sixty three

343. ## 8th grade

is 53 a monomial

344. ## Physics

A person walks 2.8597x10^1 m East, then turns around and walks 8.7898x10^1 m West. The total time to walk this distance was 4.4004x10^2 s. What is the velocity of the walker, expressed to 3 significant figures? Note: Your answer is assumed to be reduced to

345. ## 6th grade

What physical property could you use to separate sand and sugar? How would you do it?

346. ## physics

A object is throw up with a speed of 25m/s. suppose that the gravity is 10m/s^2. Define the position and the velocity of the particle for the following times: 1second, 4second and 10second

347. ## Math

Ineed to find out, one fourth of y. I think is 1/4 not sure! Thanks

348. ## statistics

a math test has a mean of 43 and a standard deviation of 17.0. find the corrresponding z scores for a test score of 13 and a test score of 59. show work

349. ## Science

Use the law of conservation of mass to explain why a rusty nail weighs more than the original nail.

350. ## math

derek planted a garden in the shape of a square 32 feet on each side. The garden has a stream on one side, but he plans so build a fence on the other three sides. If he puts a post every 8 feet, how many posts will he need?

351. ## statistics

a math test has a mean of 43 and a standard deviation of 17.0. find the corresponding z scores for a test score of 13 and a test score of 59. show all work.

352. ## Physics

A person walks 2.8597x10^1 m East, then turns around and walks 8.7898x10^1 m West. The total time to walk this distance was 4.4004x10^2 s. What is the velocity of the walker, expressed to 3 significant figures? Note: Your answer is assumed to be reduced to

353. ## science

What physical property could you use to separate sand and sugar? How would you do it?

354. ## Algebra

Homework help please: algebra inequality 0.3 - 0.5n + 1 is greater than or equal to 0.4

355. ## intro to economics

a draft system, whether professional sports or the military, enable those who are hiring to A.avoid paying a living wage B.produce what they produce at a lower cost C.educe the cost of labor D.transfer part of the cost of labor to someone other than

356. ## Math

do you mean 1/4 x y or 1/4 divided by y?

357. ## Math-Calculus

If f(x)=5ex+4xe find f'(x) .

358. ## math

Why is 24,005 greater than 8,999?

359. ## double negatives

the great white shark doesnt usually attack no person unless it confuses the person for a sea lion or seal

360. ## Algebra

-4 - 2n + 4n > 7 - 4

361. ## Chemistry

Hi, I have to take chemistry placement test for college this week. Does anyone here have advice for studying to prepare for the test? I took chemistry in high school 2 years ago so I don't remember anything.

362. ## physics

A stone is thrown vertically upward with a speed of 11.5 m/s from the edge of a cliff 95.0 m high. (a) How much later does it reach the bottom of the cliff? (b) What is its speed just before hitting? (c) What total distance did it travel? For (c), the

363. ## Physics

The space shuttle releases a satellite into a circular orbit 440 km above the Earth. How fast must the shuttle be moving (relative to Earth) when the release occurs?

364. ## math

Extend the pattern to complete the table Input 1234567 output 1 8 27 ? ? ? ?

365. ## math

name the property illustrated by this equation, and describe the meaning of the property x times 5 =5x

366. ## chemistry

Enter the net ionic equation for the reaction of aqueous sodium chloride with aqueous silver nitrate

367. ## The Nineteenth Century

Which one of the following musical notations allows performers to improvise slightly with the rhythm? A. Sostenuto B. Moderato C. Allegretto D. Rubato

368. ## math

Which figure in the pattern below will have 99 squares? Figure 1 (picture of 1 square) Figure 2 (picture of 3 squares) Figure 3 (picture of 5 squares)

369. ## Geometry

the measure of the supplement of an angle is 40 more than two times the measure of the complement of the angle find the measure of the angle

370. ## physics

A student librarian picks up a 2.2 kg book from the floor to a height of 1.10 m. He carries the book 7.8 m to the stacks and places the book on a shelf that is 0.35 m above the floor. How much work does he do on the book?

371. ## Analytical Chemistry

I am trying to find moles of IO3 from Cu(IO3)2 10 ml and standardized sodium thiosulfate (Na2S2O3.5H20) .28 M. My calc is: 0.28 Moles Na2S2O3.5H20 * (2 moles of S2O3/1 mole Na2S2O3.5H20)* (2 moles of (IO3)/1 mole Cu(IO3)2= (1.12/.01 L) but that is why to

372. ## math

use words to describe the rule of the following sequence.Then find the next three ters of the sequence.2,3,and6 to illustratethe associative property of multiplication

373. ## Algebra 1

The difference between the length and width of a triangle is 7 units. The perimeter is 50 units. What are the dimensions?

374. ## Math

Margarit liked to balance things. She balanced 3 pencil sharpeners and 2 one gram blocks witha 100 gram weight and another one gram block. She let x stand for the weight of one pencil sharpener and she claimed that x=30 grams. Was she correct? If not, how

375. ## chemistry prt 2

What is the net ionic equation of the reaction of MgCl2 with NaOH

376. ## chemistry prt 3

What is the net ionic equation of the reaction of MgSO4 with NaOH

377. ## Math

In Mathematics: how much interest will you have to pay for a credit card balance of \$554 that is one month overdue if a 20% annual rate is charged?

378. ## math anaylsis

what is x^2+54+800 in vertex form?

379. ## statistics

You want to determine if your widgets from machine 1 are the same as machine 2. Machine 1 has a sample mean of 5 and a population standard deviation 1 and a sample size of 4. Machine 2 has a sample mean of 8 and a population standard deviation of 2 with a

380. ## Algebra

please show steps solve 9 - (9)squared > 10x - x

381. ## physical science

and elevator lifts five passengers 30 m in 24 sec. the power is 15000 w. what is the total weight of the elevator and passengers? ha know that?

382. ## Chemistry

How can i explain the key features of the periodic table relate to the conclusions after a titration experiment

383. ## math

the deck in hope's backyard is round. It has 5 posts evenly spaced around the edges to support a trellis. For her birthday party, shewants to connect each post to all the other posts with crepe-paper streamers.How many streamers will she need?

384. ## spanish

what form do u use in vivir ex. mi familia (vivir) cerca del parque

385. ## Algebra

x^2+6x-44/x+9 X squared plus six X minus 44 divided by X+9. Having a hard time with this problem. I need someone to help me step by step or give me some pointers please? Thank you.

386. ## Chem

I have no idea What to do. What does it mean by 'draw what you think the visible range spectrum of this dye would look like.' To get the A, I used Beer's law. So I got 9.265nm for Absorbance. What should I do for the next? The question is ----Next Simon

387. ## chemistry

what is the mass in kilograms of 750 mL of a substance that has a density of 0.930 g/mL?

388. ## ECONOMICS HELP

a draft system, whether professional sports or the military, enable those who are hiring to A.avoid paying a living wage B.produce what they produce at a lower cost C.educe the cost of labor D.transfer part of the cost of labor to someone other than

389. ## spanish

cuando (regresar) a mi casa mi familia y yo (desayunar). luego voy a la escuela what it be translated in to the form by the subjects

390. ## spanish 1

durante el dia (pasar) tiempo con mis amigos, what would be the form for the subject

391. ## chem

Which has highest boiling point? H20, H2S, H2Se, H2Te i know its H20, but why? is it because its dipole dipole? does it have to do with electronegative, or polarity?

392. ## Music

Jody says that atonal harmony establishes a harmonic center of gravity. Sean says that atonal harmony doesn't have a harmonic center of gravity. Who is correct? A. Only Jody is correct B. Only Sean is correct C. Both Jody and Sean are correct D. Neither

393. ## chemistry

if 30ml of .150 M CaCl2 is added to 22.5ml of .1 M AgNO3, what is the mass of the AgCl precipitate?

394. ## physics

A stone is thrown vertically upward with a speed of 11.5 m/s from the edge of a cliff 95.0 m high. (a) How much later does it reach the bottom of the cliff? (b) What is its speed just before hitting? (c) What total distance did it travel? For (c), the

395. ## math

derek planted a garden in the shape of a square 32 feet on each side. The garden has a stream on one side, but he plans so build a fence on the other three sides. If he puts a post every 8 feet, how many posts will he need?

396. ## Intro to Eco Help

supply curves slop upward to the right because.. higher prices attract resources from other uses?

397. ## statistics

I.use the chebyshev's theorem to find out what percentage of the values will fall between 201 and 257 for a data set with a mean of 229 and standard deviation of 14. II. use the emperical rule to find out two values 68% of the data will fall between for a

398. ## statistics

rank the following data in increasing order and find the position and value of the 94,51st percentile. show all work. 4,5,4,9,9,1,0,7,4,8,0,9

399. ## statistics

the following data lists the average monthly snowfall for jan 15 cities around us: 34 9 28 24 0 46 34 20 1 38 5 16 32 26 25 find the mean, variance, and standard deviation

400. ## spanish1

por la noche yo (escuchar) musica o (bailar) en mi cuarto. Mis padres (leer) revistas o (ver) la tele, y mi hermano (montar) en monopatin con sus amigos

401. ## spanish1

por la noche yo (escuchar) musica o (bailar) en mi cuarto. Mis padres (leer) revistas o (ver) la tele, y mi hermano (montar) en monopatin con sus amigos pls help the right form for the subject

402. ## statistics

starting with the values 70 and 100, add 3 data values to the sample so that the mean is 76. the median is 82 and the mode is 82. show work

403. ## science

what is the power of a machine that does 1800 N-m of work per minute?

404. ## math

IAm greater then 4tens and less than tens i have 9 ones what number am i?

405. ## spanish

por la noche yo (escuchar) musica o (bailar) en mi cuarto. Mis padres (leer) revistas o (ver) la tele, y mi hermano (montar) en monopatin con sus amigos pls help me in correct form to change wod in parenthesis

406. ## Marketing

what is product development and what is product pentration

407. ## statistics

rank the following in increasing order and find the position and value of the 91st percentile show all work. 4,,5,4,9,9,1,0,7,4,8,0,9

408. ## Chemistry

How can i explain the key features of the periodic table relate to the conclusions after a titration experiment The experiment was the preperation of a standard solution of sodium carbonate and titration for the equation between hydrchloric acid and sodium