# Questions Asked onOctober 3, 2010

1. ## College Chemistry

I balanced the equation: HBr(aq) +NH3(aq)->NH4Br I need to find the ionic equation and the net ionic equation

2. ## physics

A stream is 30. meters wide and its current flows southward at 1.5 meters per second. A toy boat is launched with a velocity of 2.0 meters per second eastward from the west bank of the stream a. what is the magnitude of the boat's resultant velocity as it

3. ## Biology

In what situations would sampling work best for estimating population size, in what situations would mark and recapture work best and why?

A spider has 8 legs. An ant has 6 legs. There are a group of spiders and a group of ants. The groups have equal numbers of legs. What is the least number of spiders and ants in each group.

5. ## chem

whats the net ionic equation for the following reaction AgNo3(aq)+Na2SO4(aq) answer 2Ag+(aq)+SO42- (aq)___> Ag2So4(s) correct?

6. ## Chemistry

H2O (l) requires the largest amount of energy to raise the temperature of 25.0g H2O of the substance from 15.0 *C to 37.0 *C. Calculate the energy. Hg (l) has the largest temperature change when 550 g of the substance absorbs 10.7kJ of energy. Calculate

7. ## Chemistry

What happens when magnesium is added to Maleic and Fumaric acid? What gas is released from this reaction? I was also wondering if their are any differences between how each acid reacts with the magnesium because one is cis and the other trans. What happens

8. ## Organic Chemistry - Extraction

You have 100 mL of a solution of benzoic acid in water; the amount of benzoic acid in the solution is estimated to be about 0.30 g. The distribution coefficient of benzoic acid in diethyl ether and water is approximately 10. Calculate the amount of acid

At her wedding, Jennifer lines up all the single females in a straight line away from her in preparation for the tossing of the bridal bouquet. She stands Kelly at 1.0 m, Kendra at 1.5 m, Mary at 2.0 m, Kristen at 25 m, and Lauren at 3.0 m. Jennifer turns

10. ## chemistry

what is the general formula for a hydrate?

11. ## Chemistry

Suppose you tried to combine 42 grams of magnesium with 45 grams of oxygen. Which of the two substances would be left after the reaction? How much magnesium oxide will be formed?

12. ## Chemistry

Redox titrations are used to determine the amounts of oxidizing and reducing agents in solution. For example, a solution of hydrogen peroxide,H2O2, can be titrated against a solution of potassium permanganate, KMnO4. The following equation represents the

13. ## Chemisty

How can naphthalene be separayed from a mixture of KBr and Sand? How can you separate NiCO3 from NaCO3 in detail? How can you separate AgCl from NaCl in detail?

14. ## Physics

A car is traveling at 54.2 km/h on a flat highway. The acceleration of gravity is 9.81 m/s^2. PART 1: If the coefficient of kinetic friction between the road and the tires on a rainy day is 0.131, what is the minimum distance needed for the car to stop?

A soccer player kicka a ball with an initial velocity of 10 meters per second at an angle of 30 degress above the horizontal. the magnitude of the horizontal component of the ball's initial velocity is

If a car is accelerating downhill under a net force of 3674, what additional force would cause the car to have a constant velocity?

17. ## chemistry

A nickel has a mass of 5.000 grams and is composed of 25% nickel and 75% copper. What is the mass of copper in the nickel? How many moles of copper are in this nickel? How many copper atoms are in this nickel?

18. ## Math

Of people who died in the US in recent years, 86% were white, 12% were black, and 2% were Asian. (This ignores a small number of deaths among other races.) Diabetes cause 2.8% of deaths among whites, 4.4% among blacks, and 3.5% among Asians. The

19. ## College Chemistry

What is the oxidation number of (NH4)2SO4

20. ## anna

From the poem "The Wanderer" What is the plight of the wanderer "earth-walker"? How did he become what he is and what is he seeking?

21. ## College Chem

Calculate the number of grams required to make 250 mL of a 0.020 M KIO3 solution.

22. ## physics

A bob of mass = 0.250 is suspended from a fixed point with a massless string of length = 23.0 . You will investigate the motion in which the string traces a conical surface with half-angle = 25.0. What tangential speed must the bob have so that it moves in

23. ## Chemistry

How many molecules of Cl2 would be formed from the reaction mixture that produces the greatest amount of products? 4HCl + O2 --> 2H2O + 2Cl

24. ## Math

A laboratory has 60 cubic centimeters of a solution that is 40% HCI acid. How many cc of a 15% solution of HCI acid should be mixed with the 60 cc of 40% acid to obtain a solution of 25% HCI? How much of the 25% solution is there? I don't know how to write

25. ## Physics

An airplane flies at 200.0 km/h relative to the air. What is the velocity of the plane relative to the ground if it flies during the following wind conditions? a. a 50.0-km/h tailwind b. a 50.0-km/h headwind.

26. ## physics

The amplitude of a system moving in simple harmonic motion is doubled. Determine by what factor does period change since T=2pi(m/k)^(1/2), so it doesnt change. When i typed in unchanged, it says wrong since "the correct answer is not zero". Should i put in

27. ## Chemistry

Consider the following errors that could be made when running TLC. Indicate what should be done to correct the error. a) a two-component mixture containing 1-octene and 1,4-dimethylbenzene gave only one spot with an Rf value of .95. The solvent uses was

28. ## Physics

To stop a car, you require first a certain reaction time to begin braking. Then the car slows under the constant braking deceleration. Suppose that the total distance moved by your car during these two phases is 56.7 m when its initial speed is 80.0 km/h,

29. ## College Chemistry

Sodium hydroxide is used extensively in acid-base titrations because it is a strong inexpensive base. A sodium hydroxide solution was standardized by titrating 27 mL of 0.1628 M standard hydrochloric acid. The initial buret reading of the sodium hydroxide

30. ## Maths - trig

Solve 3cos2x - 7cosx = 0, when 0

31. ## Physics, Science

A 26 kg block is connected to an empty 1 kg bucket by a cord running over a frictionless pulley. The coefficient of static friction between the table and the block is 0.435 and the coefficient of kinetic friction between the table and the block is 0.320.

32. ## Physics

A coin is placed 17.0 from the axis of a rotating turntable of variable speed. When the speed of the turntable is slowly increased, the coin remains fixed on the turntable until a rate of 33 is reached and the coin slides off.What is the coefficient of

33. ## chemistry

To analyze for barium in an unknown white powder, an excess of sodium sulfate solution was added to a 0.576 g sample of the powder dissolved in water. A white precipitate of BaSO4 was isolated, dried, and found to weigh 0.438 g. What is the mass percent of

34. ## Physics

Researchers have found that a gecko's foot is covered with hundreds of thousands of small hairs (setae) that allow it to walk up walls and even across ceilings. A single foot pad, which has an area of , can attach to a wall or ceiling with a force of 11 .

35. ## College Chem

I need to be able to describe how to prepare 20 mL of a 0.0050 M KIO3 solution from a stock solution with a concentration of 0.020 M.

36. ## Chemistry

a piston performs work of 210. L atm on the surroundings, while the cylinder in which it is placed expands from 10. L to 25L. at the same time, 45J of heat is transferred from the surroundings to the system. Against what pressure was the piston working?

37. ## math

An elf has a staircase with 10 steps to climb. Each step it takes can cover either one stair or two stairs. In how many ways can the elf climb the stairs? For n stairs?

38. ## Physics

What is the distance from the Earth's center to a point outside the Earth where the gravitational acceleration due to the Earth is 1/20 of its value at the Earth's surface?

39. ## English

11. Upon the death of Spitz in The Call of the Wild, Francois and Perrault decide that the new sled-team leader should be

40. ## Physics

A 83.0-kg person stands on a scale in an elevator. What is the apparent weight when the elevator is (a) accelerating upward with an acceleration of 1.80 m/s2

41. ## chemistry

Oxalic acid (H2C2O4) can be used to remove rust according to the following balanced equation: Fe2O3 + 6H2C2O4 --> 2Fe(C2O4)33- +3H2O + 6H+ Calculate the number of grams of rust that can be removed by 5.00 x 102 ml of a 0.122M solution of oxalic acid.

42. ## Physics

Superwoman is hovering above the ground when a person free-falling goes by her at a terminal velocity of 140 km/h. Unfortunately, the parachute does not open. Fortunately, Superwoman is around. If it takes her 1.9 s to realize the person is in distress,

43. ## math

using numbers 1-12 make all sides of a square equal 26 using 4 numbers a time

44. ## Organic Chemistry

Design a flowchart for the separation of a mixture that contains toluic acid, p-bromo-aniline, and anthracene. Whenever a reaction occurs, write the reaction completely.

45. ## Geometry

If a whole bunch of lines(no two parallel, no 3 concurrent) intersects in a plane 2926 times, how many lines are a whole bunch?

46. ## Physics

An airplane normally flies at 280 km/h. What is its airspeed if it experiences 80 km/hr headwind?

47. ## Finance

moussawi ltd's outstanding bonds have a $1000 par value, and they mature in 5 years. their yield to maturity is 9%, based on semiannual compounding, and the current market price is$853.61. what is the bonds annual coupon interest rate?

48. ## Chemistry

What would the molarity of 50 mL of 3% hydrogen peroxide be if it's volume/volume? I know how to do weight/volume but not this, someone help?

49. ## PHYSICSS

A block is projected up a frictionless inclined plane with initial speed v1 = 3.40 m/s. The angle of incline is è = 31.1°. (a) How far up the plane does it go?(m) (b) How long does it take to get there? (s) (c) What is its speed when it gets back to the

50. ## physics

A dart gun is fired while being held horizontally at a height of 1.00 m above ground level and while it is at rest relative to the ground. The dart from the gun travels a horizontal distance of 5.00 m. A college student holds the same gun in a horizontal

51. ## Physics

An airplane normally flies at 280 km/h. What is its airspeed if it experiences 80 km/hr headwind?

52. ## Physics

The board sandwiched between two other boards weighs 92.6 N. If the coefficient of friction between the boards is 0.587, what must be the magnitude of the horizontal forces acting on both sides of the center board to keep it from slipping downward? Answer

53. ## physics

A car with an initial speed of 23.7 km/h accelerates at a uniform rate of 0.92 m/s^2 for 3.6s. Find the final speed and the displacement of the car during this time.

54. ## managerial eccon

Suppose that a firm is currently employing 30 workers, the only variable input, at a wage rate of $60. The average product of labor is 30, the last worker added 12 units to total output, and total fixed cost is:$3,600. what is the averge variable cost?

55. ## Chemistry

A volume of 50.0 mL of aqueous potassium hydroxide was titrated against a standard solution of sulfuric acid. What was the molarity of the KOH solution if 19.2 mL of 1.50 M H2SO4 was needed? The equation is 2KOH(aq) +H2SO4(aq)-» K2SO4(aq)+2H2O(l)

56. ## Chemistry

If the initial pressure of NH3(g) is 0.7317 atm, calculate the % of NH3(g) left over after the reaction reaches equilibrium according to the balanced equation. The value of Kp at 500.0 °C is 67100.00. The initial pressure of the reaction products is 0

57. ## Statistics

What z-value corresponds to the 18th percentile?

58. ## physics

A car is moving down a street at 51 km/h. A child suddenly runs into the street. If it takes the driver 0.97 s to react and apply the brakes, how many meters will the car have moved before it begins to slow down?

59. ## Chemistry

25.0 mL of a NaCl solution (concentration unknown) was found to react with 20 drops of the chloride test solution from the PU Chloride Test Kit. Calculate the mass of NaCl (in grams) in this solution. Calculate the mass of NaCl required to prepare 0.250 L

60. ## Physics

Consider the earth following its nearly circular orbit about the sun. The earth has mass 5.98*10^24 and the sun has mass 1.99*10^30. They are separated, center to center, by r=150 million k. What is the size of the gravitational force acting on the earth

61. ## science

In defining the sizes of orbitals, why must we use an arbitrary value, such as 90 percent of the probability of finding an electron in that region?

62. ## Essay

I'm writing an essay on the topic " The most memorable moment in your life" and I was wondering if you guy could give me suggestions on how I could start my introduction. Thanks ( The most memorable moment I chose was the first day of my summer vacation)

63. ## Physics

three vectos are shown in fig. 3-32. their magnitudes are given in arbitrary units. Determine the sum of the three vectors. Give the resultant in terms of (a) components, (b) magnitude and angle with the x axis. (3-32 --the figure has three rays all

A stream is 30. meters wide and its current flows southward at 1.5 meters per second. A toy boat is launched with a velocity of 2.0 meters per second eastward from the west bank of the stream a. what is the magnitude of the boat's resultant velocity as it

65. ## Chemistry

An ore contains Fe3O4 and no other iron. The iron in a 51.98 gram sample of the ore is all converted by a series of chemical reactions to Fe2O3. The mass of Fe2O3 is measured to be 32.8 grams. What was the percent Fe3O4 in the sample of ore? Answer in

66. ## Science

If an astronaut could hop 40 cm high on Jupiter, how high could he or she jump on Earth?

67. ## English

In the Minister's Black Veil by Nathaniel Hawthrone. What reasons does Hooper give for not wanting to remove his veil? I came up with one reason: that there is a Black Veil on everyone But what will the other reasons be? "Why do you tremble at me alone?"

68. ## chemistry

using the values for heat of fusion, specific heat of water, or heat of vaporization, calculate the amount of heat energy. Calories needed to warm 20.0g of water at 15 degrees Celsius to 72 degrees Celsius (one step) Show work please

69. ## Chemistry

A sample of an ideal gas at 15.0 atm and 10.0 L is allowed to expand against a constant external pressure of 2.00 atm at a constant temperature. Calculate the work in units of kJ for the gas expansion. (Hint: Boyle's law applies) Please explain thoroughly!

70. ## physicsssss

two blocks are connected over a pulley. The mass of block A is 10 kg and the coefficient of kinetic friction between A and the incline is 0.24. Angle èof the incline is 30°. Block A slides down the incline at constant speed. What is the mass of block B?

71. ## College Chemistry

What is the oxidation number of Cr2(SO4)3

72. ## math

8 over 13 to a decimal number rounded to the nearest hundredth

236. ## lll

what is the min # for a few?

237. ## Biology

How does a plant growth regulator differ from a plant growth hormone?

238. ## chemistry

what would be the mass of an Au sample whose volume is 2.85mL?( the density of gold is 19.3g/mL)

239. ## Math

How would you explain this problem? [(8*2)- 13]^3+(4-1)^2+4-2*3+|3|-|-6|=?

240. ## Physics

At a time when mining asteroids has become feasible, astronauts have connected a line between their 3760-kg space tug and a 6100-kg asteroid. Using their ship's engine, they pull on the asteroid with a force of 490 N. Initially the tug and the asteroid are

241. ## Physics

The jet is moving at 500 m/s in a verticle loop, with a minimum radius of 4000 m. Calculate the 69-kg pilot's effective weight (the force with which the seat pushes up on him) at the bottom of the circle, and at the top of the circle (assume the same

242. ## Math

Amy purchased a pair of shoes for \$52.83 during a 25% off sale. what was the regular price?

243. ## chemistry

the mechanisms between propanone and sodium hydrogensulphite

244. ## English

Thank you very much for your corrections. Here are some more sentences I'd like you to check. 1.Kurtz wanted to realize (to fulfil) his highly moral ideals but he failed. He wanted his ideals to come true but he failed because he was left alone to face the

245. ## Biology

I can distinguish living from non-living material? I can identify and describe five basic characteristics of life and give an example of each. I can How Dr.Penelope Boston is preparing to look for evidence of life on mars.

246. ## criminal procedure

In a hearing challenging the probable cause upon which an arrest was based, a warrantless arrest is viewed the same as an arrest based on a warrant. True or false ?

247. ## math

N and P are integers greater than 1 5N is the square of a number 75NP is the cube of a number smallest value for N+P IS what? thank you so much

248. ## AP world history

i have to write a DBQ promt question for the interaction between humans and the enviornment (demography and disease, migration,technology, and patterns of settlement) about roman empire

249. ## Math

How would I simplify this? 2x-(9x-4)

250. ## Science

If Earth's mass were smaller, how would Earth's gravity be affected?

251. ## Algebra

How to solve this x(1+x)=2 Find all the real solutions I can't remember how to solve this... the answers are -2, 1 I think...

252. ## historical cultural

The Triple Alliance represented what change in German foreign policy?

253. ## history.

evaluate how the age of enligtenment is a response to the age of absolutism. help please. please.

254. ## English

1. Many animals in the woods have been asleep all winter. 2. Birds have been away. 3. Under the snow, the ground has been hard. (In the sentences above, the present participle was used. What does the present participle refer to? Does it refer to

255. ## Algebra

In cost in millions of dollars to remove x% of pollution is a lake modeled by C=5,000 over 200-2x. (a) What is the cost to remove 50% of the pullutant.

256. ## math

Find the drivative of the function 4ã(x^2 )+ 2/(3X)^3 + 3/sec⁡X - 5/cot⁡X=

257. ## English

When you are writing an essay that refers to two works and you are using a quote, do you (Alveraz, 30) or just put (Alveraz 30) with no comma. Thanks

258. ## algebra

you are planning to spend no less than 6000 and no more than 10000 on a landscaping project. Write an inequality to show how much you are willing to spend.

259. ## Algebra

graph inequality on a plane 4x+5y is less than or equal to 20

260. ## Algebra 2

When you solve 6 + 5|2r-3|≥ 4, is the answer r ≥ 13/10 and r ≤ 17/10?

261. ## math

how do you describe and correct errors when writing the number 81,700,000 in scientific notation?

262. ## college english

I have to write an essay on my neighborhood. What questions or things can I include? I need ideas please.

263. ## Math

How do I simplify this expression? 2x+7+3x

264. ## algebra

solve the absolute value equation |1+6c|-7=-3

265. ## philosophy of religion

Explain thoroughly and elaborately what Martin Buber means by real atheism as the eclipse of God. - any help will do. i'm desperate. i'm having a hard time understanding this subject. you can just tell me what atheism is according to buber even not

266. ## physiology

what is the relatioship between electrical activity and muscle force produced ?

267. ## math

there are 267 students and teachers in a school. the ratio of students to teachers is 25:2 . How many students and teachers are there?

268. ## chemistry / physics

the specific heat capacity of seawater is 3900 j/kg degrees celcius. how much energy is needed to heat 500g of seawater from 20 degrees celcius to 90 degrees celcius? if not i need to know how to work it out

269. ## college biostatistics

if the mean bp is 110 and the standard deviation is 15 where would 95% of population be

270. ## calc

y(s)= 1/(6(s^2)) - 5/s Find Y'(s)

271. ## social studies

I messed up on my other social studies question. i ment to ask if the BUILDER of the taj mahal had his hands cut off by emperor shah jahan. Is this true? i need proof if this is true. thanks alot

272. ## physics- urgent

determine the estimated uncertainty for the area of circle with a radius of 10.45+-0.5cm

273. ## history

what are 12 good points about king henry viii??

274. ## 8th grade Social Studies

How does the freedom to petition protect us from the federal government?

275. ## chemistry

what is the equation for gamma decay?

276. ## English composition

Music during slavery: A call to arms or a panacea?

7-x+5=4

278. ## Science of Biology

Name three ways that the science of biology has/does, or might impact you as an individual. SOMEONE PLEASE HELP ANSWER THIS QUESTION!!! THANKS :)

279. ## math 115

graph shows the yearly food cost for a family. 30% of the food cost rom 2002 was spent at restaurants. How much money did they spend that year at restaurants?

280. ## precalculus

Horizontal Translation and dialation Problem : let f, g, and h be defined f(x)= x2 -2< or equal to x < or equal to 2 g(x)=x-3 for all real valuse of x h(x) = 1/2 x for all real values of x a. f(g(x))= f(x-3). What transformatioon is applied to function f

281. ## math

Horizontal Translation and dialation Problem : let f, g, and h be defined f(x)= x2 -2< or equal to x < or equal to 2 g(x)=x-3 for all real valuse of x h(x) = 1/2 x for all real values of x a. f(g(x))= f(x-3). What transformatioon is applied to function f

282. ## Hum176

What is comparing and contrast coverage?

283. ## math

(0.3)-0.05(0.3)

what is the best estimate of 89+12 a 90 b. 100 c. 80 d. none of these

285. ## Math

x+1 - x+2 = ? --- --- 2x-8 12-3x

286. ## math

looking for any mathematical characteristic of the number 13 for a math project

287. ## physics- urgent

an object travels at a rate of 48.5 km/sec. how many cm/min would that be

288. ## Math

How would I simplify this? Explain please!!! 7(2x+2)-9(-1+6x)

289. ## Math

h(x)=-12x2 -4x+5

290. ## Math

add, simplify if possible. z+r/zr^2 + 8z+r/z^2r

291. ## math

89 92 83 96 and 99 what the mean

292. ## social studies

what are some major characteristics in the eastern hemisphere?

293. ## 12/6

WHAT IS THE RAZON 2 OR 6

294. ## math

simplify 3.04-1.935