# chemistry! URGENT

61,843 results, page 20
1. ## physics (urgent)

Two identical gas cylinders each contain 20.0 kg of compresses air at 1.00 x 106 pa and 275 K. One of the cylinders if fitted with a safety valve that releases air into the atmosphere if and only if the pressure in the cylinders raises above 1.10 x106 pa
2. ## Calculus (urgent!!)

A particle moves with its position given by x=cos(2t) and y=sin(t), where positions are given in feet from the origin and time t is in seconds. A)Find the speed of the particle. Speed = ____________ (include units) B)Find the first positive time when the
3. ## Physics (URGENT!)

-vehicle 1: 2,060lbs -vehicle 2: 5,800lbs -both roads are 45mph -The cars were impacted at right angles -roadway was dry, 69 degrees -friction between tire & road: .60=mu -skid marks (PRIOR to impact): v1=20ft, v2=7ft. *you can find the entire problem w/
4. ## Social Studies (URGENT)

During the immigrant experience in the early 1800s U.S. is said to be a "melting pot", and Canada a "mosaic". a.) What do these two terms mean to you? Melting pot describes the blending of cultures into a single nation. Cultural mosaic describes the mix of
5. ## Economics

Yeah, so I'm in urgent need of help with this homework. 1. Assume that in a perfectly competitive market, a firm's costs and revenue are: Marginal cost = average variable cost at \$20 Marginal cost = average total cost at \$30 Marginal cost = average revenue
6. ## English (Urgent)

In John Cheever's story reunion, what do the restaurants symbolize. Why does Charlie call hi father daddy at the end of the story? Examine the first and last sentences of the story. What is common and why? How do you interpret the ending of the story? Does
7. ## English

I forgot to include the following sentences. They are really urgent. 1)He hadn't read a book since he was a boy/ "by the time he was a boy he hadn't read a book (is a mistake?) 2) She told me she had dumped him/broken/finished with him. (are they all
8. ## Chemistry

Compare the natural chemistry that takes place in the environment with the chemistry that takes place due to manmade factors like pollution. Discuss the effect of pollution at the local, regional, national, and global level.
9. ## Urgent - physics

Air molecules and dust particles in the atmosphere will scatter sunlight. From a consideration of the position of the sun, estimate the direction of incidence of the sun's rays on the atmosphere. In what direction will an observer on the earth's surface
10. ## Clarify (URGENT)

In pairs (make sure you put both names on the answer sheet), create strategies and possible dialogue (min. 1 per topic) for communicating in the following situations: Saying no to sexual involvement Discussing whether or not to become sexually active
11. ## physics, help urgent!

charge Q = +4.5 ƒÝC is located at the origin and is fixed so that it cannot move. A small object with mass m = 2.0 g and charge q = +8.0 ƒÝC is released from rest at point A on the x-axis at x = 2.0 cm. The small object moves without friction along the
12. ## PHYSICS - URGENT

a ball of mass m1 and a block of mass m2 are attached by a lightweight cord that passes over a frictionless pulley of negligible mass. the block lies on a frictionless incline of angle theta. (a) draw the free body diagrams (b) express newton's second law
13. ## Math Help 2 Questions Urgent!

1. The Pythagorean Theorem can be used to find distances between two points on a grid. But what about finding distances in three-dimensional space? Consider a rectangular box, which has length l, width w, and height h. What is the distance from one corner
14. ## Science Urgent😖😖😖

Why most organisms reproduce A( organisms must reproduce to maintain genetic similarity in the species B( organisms must reproduce to continue to build genetic diverse city into the species C( organisms must reproduce to continue the species D( organisms
15. ## English

Could you please check this paragraph? It is really urgent. Thank you!! 1)My name is Michele and I was born in Torino on 23 march 1997. When I was three years I went to Rome with my family. 2) Now I have got 14 years old and I go to secondary school . 3)I
16. ## help...urgent..calculus..please show tthe way to s

Sony Ent. is marketing a new smartphone. It determines that in order to sell x smartphones, the price per product must be p=280-0.4x. It also determine that the total cost of producing x smartphones is given by c(x)=5000+0.6x^2 . a. Find the total revenue,
17. ## soial studies-URGENT!!NEED BY 8:25 A.M. TOMORROW!

Who was an important person in Christianity,islam and judaism, where were they started and when were they discovered? THANX!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! :) Type in these different religions in a google search or Wikipedia, find the name of a person that
18. ## help...urgent..calculus

Sony Ent. is marketing a new smartphone. It determines that in order to sell x smartphones, the price per product must be p=280-0.4x. It also determine that the total cost of producing x smartphones is given by c(x)=5000+0.6x^2 . a. Find the total revenue,
19. ## Calculus (urgent!!)

A particle moves with its position given by x=cos(2t) and y=sin(t), where positions are given in feet from the origin and time t is in seconds. A)Find the speed of the particle. Speed = ____________ (include units) B)Find the first positive time when the
20. ## English

I'm posting you a paragraph I wrote containing phrasal verbs. This is more urgent than the previous one. Thank you. 1) My friend looked very upset so I thought she needed to brighten up. I invited her to the cinema and she accepted. I thought popcorns
21. ## URGENT MATH

A pair of jeans is on sale for 25% off the original price. Which expression represents the sale price? If the original price of the jeans is \$40,evaluate the expression to find the sale price. s=p-0.25 p;\$30 s=p-25:\$15*** s=p-0.25p;\$10 s=p-0.25;\$39.75

Sorry to repost this, again, but I still don't understand. Newton’s Law of Gravity specifies the magnitude of the interaction force between two point masses, m1 and m2, separated by the distance r as F(r) = Gm1m2/r^2. The gravitational constant G can be
23. ## Algebra

(I am not sure how to get the y value for part C and the whole part D) (I answered a couple of them but am not confident on my answers, so can you please tell me if my answers are not correct to the ones I answered and for the ones I haven not answered
24. ## Math Urgent

In a survey of 63 people, 23 people subscribe to magazine A, 21people subscribed to magazine B,and 17 people subscribed to magazine C. For any two of the magazines,4 people subscribed to both magazines but not to the third magazine. If 5 people in the

A spring of negligible mass, spring constant k = 82 N/m, and natural length l = 1.2 m is hanging vertically. This is shown in the left side where the spring is neither stretched nor compressed. In the central one, a block of mass M = 5 kg is attached to
26. ## math (urgent help needed)

Seeds of type A and type B are sold in a packet each must contain a)both type a and type b seeds b)at least twice the number of type b c)as there are type a seeds no more thanm 12 seeds 1)state the minimum number in each packet of type a and type b seeds.
27. ## PHYsics URGENT

a 7.0 kg object weighs 55 N when submerged and weighed in water. A) what is the value of the buoyant force of the water on the object b) what weight of water is displaced by this object? c) water weighs 0.0098 N per cubic centimeter. What volume of water
28. ## Math - Need urgent help!

A residential property is assessed for tax purposes at 40% of its market value. The residential property tax is 3 1/3% of the assessed value and the tax is \$1200. a)What is the assessed value of the property? b) What is the market value of the property?
29. ## College Algebra

(I am not sure how to get the y value for part C and the whole part D) (I answered a couple of them but am not confident on my answers, so can you please tell me if my answers are not correct to the ones I answered and for the ones I haven not answered
30. ## Economics - URGENT

Suppose we now care about the long run decisions of a firm that has a production function of the form q = 4L^1/2 + K Suppose w = 1 and r = 0.5 Assume that, at the beginning when w0 = 1 and r = 0.5, the firm chose to produce q0 = 20 units of output. Then,
31. ## MATH urgent!!!

My problem: From 1992 to 1996, the annual income for all the private golf courses in the United States can be approximated by the model: I=59t^2+2254, where I is the annual income in millions of dollars and t is the year, with t=0 corresponding to 1990. 1.
32. ## Biology - URGENT Enzyme Lab

Did a catalase producing hydrogen peroxide lab, used manganese dioxide, fresh frozen liver, potato, ice, fine clean sand, etc. Basically just added hydrogen peroxide to the catalysts under diff conditions and stuff. Just don't get this question which is :

On January 5, Ebony Davis borrowed \$6,500 on a simple interest loan from a lending institution to finance her catering business. She borrows the money at a rate of 8.5% with a term ending on December 9. a. Calculate Ebony's interest on the simple interest
34. ## science-plz help, this is urgent!plz!

we did a lab on chemical change, where we had to see how a chemical change affcts mass. so we measure the mass of 20ml of copper solution, and 2cm(cubed) of steel wool, and then we mixed them into a flask. soon the steel wool turned rusy, and broke apart.
35. ## science-plz help, this is urgent!plz!

we did a lab on chemical change, where we had to see how a chemical change affcts mass. so we measure the mass of 20ml of copper solution, and 2cm(cubed) of steel wool, and then we mixed them into a flask. soon the steel wool turned rusy, and broke apart.
36. ## MATH

15. Write a function rule that represents y is 5 less than the product of 4 and x. 16. Write a function rule that represents 7 less than three fifths of b is a. 17. Write a function rule that represents the almond extract a remaining in an 8 oz bottle
37. ## physics (Urgent)!!!!!!!!!!!!!!!!!!!!!!

A merry-go-round (pictured) is sitting in a playground. It is free to rotate, but is currently stationary. You can model it as a uniform disk of mass 210 kg and radius 110 cm (consider the metal poles to have a negligible mass compared to the
38. ## Math IN URGENT NEED OF FEEDBACK

If the temperature is constant, then the atmospheric pressure P (in pounds/square inch) varies with the altitude above sea level h in accordance with the law given below where p0 is the atmospheric pressure at sea level and k is a constant. P = p0e-kh If

0.702g arsenic combines with 0.225g of oxygen to make an oxide of arsenic. When heated this produces a gas with a volume of 52cm3. How do i work out the molecular formula of the oxide when its in a gaseous state? The weight ratio will tell you, after
40. ## English

Can you please check the following sentences? It is really urgent. Thank you very much. 1) Last summer I went to South Africa with my family. In my opinion, it was the most exciting holiday I have ever had. 2) Actually, South Africa has got a lot of wild

What is the pH of a 5.06E-2 M aqueous solution of sodium acetate? I know that I would set this up the same way I did for the previous question that I posted. I am just confused on how to find the Ka. I know it is kw/kb but for what compound is what I do
42. ## Physics URGENT!!!

: A massless spring of constant k =84.8 N/m is fixed on the left side of a level track. A block of mass m = 0.5 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) is then released and
43. ## Physics URGENT!!!

A massless spring of constant k =84.8 N/m is fixed on the left side of a level track. A block of mass m = 0.5 kg is pressed against the spring and compresses it a distance d, as in the figure below. The block (initially at rest) is then released and
44. ## Physics-- urgent

A block of mass m = 3.20kg slides from rest a distance d down a frictionless incline at angle θ = 30.0° where it runs into a spring of spring constant 425 N/m. When the block momentarily stops, it has compressed the spring by 22.0 cm. (a) What is the
45. ## Plz Check my Geometry (Urgent)

***I know I've posted this several times but it's like getting skipped and or no one has gone over it so I'm posting it one more time before I go to bed. I need to have these checked by tommorrow PLEASE!*** Out of 31 questions these are ones I struggled
46. ## MATH

The cost to manufacture a product is proportional to the quantity produced, with a cost of \$270000 dollars per day when 900 items are produced. The cost to store n items is proportional to the square of n, with a daily storage cost of \$6480 dollars when
47. ## UNIT FRACTIONS URGENT~!

I have been stuck on this for hours and feel completely stupid, could someone help? Read the story problem given below. Identify what unit conversions must be made and show your unit fractions in making the conversions. Make the required conversions and
48. ## Urgent! 6th Grade History School Help

Which is true about the Athenians? a) They grew poor as a result of the Pericles' battle strategies. b) They grew rich as a result of Pericles' battle strategies. c) They grew poor as a result of the Delian League. d) They are rich as a result of the

6)Claudia y María ____________________ de México. Choices: Somos, Eres, Son, Es The answer is NOT Son or Somos My Answer: Es 9) Nosotros ____________________ mexicanos. Choices: Soy, Eres, es, Somos, Son The answer is NOT SOn, Soy, Somos My Answer: Eres
50. ## math

You randomly draw letter tiles from a bag containing the letters from the word INDEPENDENT. 1. You randomly draw an N. Then, without replacing the first letter, you pick a D. Tell whether the events are independent or dependent. Then find the probability
51. ## URGENT ECON QUESTION ABOUT DEMAND AND SUPPLY

ok this is the scenario 12. Industry: cell phones Event: 1.) cell phones are reported to cause brain tumors 2.) the cost of cell phone electronic chips are cheaper so in this scenario, demand decreases and the supply increases....thus demand shifts to the
52. ## Urgent Spanish Check

A) Read the following sentence and choose which word is not correct in the context of the sentence. 1) La examen es difícil. La? 2) El árbol es verdes. el? B) The following sentence is written in singular form. Read the sentence, then choose the correct
53. ## chemistry placement exam

has anyone taken a chemistry placement exam prior to their 1st year of college? what's it like? look up chemistry placement exam on yaahoo and there are a whole lot of websites that talk about what you are asking! hope this helps! You might browse these
54. ## URGENT MATHS

I got 2 questions and I've been stuck on them for days and its due in 2 days. 1. For a quick way of doing multiplication, you can do: for example: 81 x 89=? First you do 1x9=9 in which case you have to add '0' in front of it to make it 09. Then you add 1
55. ## math urgent

A cyclist travels 70 miles in 7 hours going against the wind and 56 miles in 4 hours with the wind. what is the rate of the cyclist in still air and the rate of the wind. rate in stir air = rate of the wind=
56. ## Physics URGENT!!!

A commuter train passes a passenger platform at a constant speed of 31 m/s. The train horn is sounded at its characteristic frequency of 330 Hz.Assume the speed of sound is 343 m/s. (a) What is the frequency detected by a person on the platform as the
57. ## Accounting urgent

Foster Glass Company purchased a fax machine on July 1, 2007 for \$1,800. The fax machine had an estimated useful life of three years and a salvage value of \$300. Assume Foster uses the double-declining balance (DDB) depreciation method. Foster decided to

I wrote the thesis but wat do i make the conclusion be...:( This is my thesis: Aldous Huxley's Brave NEw World and Emily Bronte's, "wuthring heights" describe a major struggle of being an individual again society . in Aldous Huxley's novel "Brave New
59. ## urgent physics..

Adventurous Mary tries a new game: she puts on her rollerblades and throws the ball towards the wall, lets it bounce off, catches it again, throws it right back, and so on. She notices a strange thing: after the second throw, she is unable to catch the
60. ## Physics. Need urgent help.

A scuba diver searches for treasure at a depth of 20.0m below the surface of the sea. at what pressure must the scuba device deliver air to the diver? (density of sea water= 1030kg/m^3;atmospheric pressure= 1.013x10^5 pa) another one A king's crown is said
61. ## URGENT HELP WITH DISCRETE MATH PLEASE

1. for any sets X and Y, we define the symmetric difference X ∆Y by: X∆Y = (X - Y) ∪ (Y - X) = (X ∪ Y) - (X ∩ Y) Prove the following: -for all sets A,B and C, if A - (B ∩ C) = ∅ then A- C ⊆ B - for all sets
62. ## URGENT! discrete math help please

1. for any sets X and Y, we define the symmetric difference X ∆Y by: X∆Y = (X - Y) ∪ (Y - X) = (X ∪ Y) - (X ∩ Y) Prove the following: -for all sets A,B and C, if A - (B ∩ C) = ∅ then A- C ⊆ B - for all sets
63. ## VERY URGENT SCIENCE

A science teacher was curious to see whether offering money for good grades would increase student performance on a test. The teacher offered half the students in the class \$5.00 if they got an A on their next test. The other half of the class was not
64. ## GREAT GATSBY URGENT!!!!!!!!

explain a theme in the great gatsby, multiple paragraphs What theme do you want to explain? Please post your answer here and someone may be able to critique it for you. tragedy and the american dream http://www.sparknotes.com/lit/gatsby/
65. ## urgent physics

A power line carries a current of 110 A at a location where the Earth's magnetic field has a magnitude of 0.37 Gauss (0.37·10-4 T) and points due north, very nearly parallel to the ground. Find the direction and magnitude of the magnetic force exerted on
66. ## Physics URGENT!!!

A crate of mass 52.8 kg is being transported on the flatbed of a pickup truck. The coefficient of static friction between the crate and the trucks flatbed is 0.351, and the coefficient of kinetic friction is 0.305. (a) The truck accelerates forward on
67. ## Urgent Spanish Check

La clase no es _____. Hay pocos alumnos. Grande? How would you express the following question in English?: ¿Cuántos libros hay? How many books are there? Hay muchos ____ diferentes en una escuela secundaria. cursos ¿Hay una clase de biología hoy? Sí,
68. ## As chemistry

A SAMPLE OF ANTIMONY, Ar=121.8, WAS ANALYSED AND WAS FOUND TO CONSIST OF 60% OF 121Sb AND ONE OTHER ISOTOPE. DETERMINE THE MASS NUMBER OF THE OTHER ISOTOPE IN THE SAMPLE OF ANTIMONY. please help I'm really stuck, Chemistry - bobpursley Saturday, September

demand for sulfur dioxide by coal-fired electricity electricity producers is: Firm A's demand: P= 1,000 - 80 Q Firm b's demand: P= 1,000 - 20 Q where Q is quantity of sulfur dioxide measured in thousands of tons, and P is price per ton of sulfur dioxide.
70. ## Math

In a class of 100 students, 40 offer Biology and 10 offer Chemistry and Biology .10 offer Physics and Chemistry , and 30 offer Physic and Biology . Each student offer at least one of the three subjects. The number of students who offer Biology is equal to
71. ## chemistry

Posted by Bret on Friday, March 16, 2007 at 10:44am. what is the oxidation number for nitrogen in the following? NH3 NO2 1- N2 NO2Cl N2H4 For Further Reading chemistry - bobpursley, Friday, March 16, 2007 at 11:26am We will be happy to critique your
72. ## chemistry

Describe the differance between chemistry and chemical technology. Technology is the making of applications. Chemical technology...making chemicals for practical or commercial purposes. Chemistry...the study of materials, their reactions
73. ## Math

Hi, I need urgent help with these 3 integrals problems ... been stuck on the questions and the deadline is Friday. Thanks a lot ! 1) For the green's theorem, Q: Using Green's theorem, evaluate the line integral F(r).dr counterclockwise around the boundary
74. ## Physics. Urgent

A vertical spring with a spring constant of 450 N/m is mounted on the floor. From directly above the spring, which is unstrained, a 0.30 kg block is dropped from rest. It collides with and sticks to the spring, which is compressed by 3.0 cm in bringing the
75. ## Physics URGENT!!!

The overall length of a piccolo is 30.6 cm. The resonating air column vibrates as in a pipe that is open at both ends. Assume the speed of sound is 343 m/s. (a) Find the frequency of the lowest note a piccolo can play, assuming the speed of sound in air is
76. ## physics (Urgent)!!!!!!!!!!!!!!!!!!!!!!

A gunman standing on a sloping ground fires up the slope. The initial speed of the bullet is v0= 340 m/s. The slope has an angle α= 12 degrees from the horizontal, and the gun points at an angle θ from the horizontal. The gravitational
77. ## Physics URGENT

Object 1 (mass=6.4 kg) traveling in the +x direction at a speed of 14.01m/s undergoes an inelastic collision with Object 2 (mass=5.10kg) which is at rest. Object two flies off at a speed of 11.94m/s and an angle θ2=49.8 °. The diagram below is just a
78. ## Clarify (URGENT!!)

Create strategies and possible dialogue (min. 1 per topic) for communicating in the following situations: Saying no to sexual involvement Discussing whether or not to become sexually active Talking with a partner about using protection Discussing with a
79. ## French (URGENT)

Okay, for an assignment, I have to interview my partner in French. So I wrote down the questions I would ask him in English, but I don't know enough French to translate them. Can someone please help me translate these sentences into French? What is your
80. ## physics, help! urgent!

A positive point charge q = +2.50 nC is located at x = 1.20 m and a negative charge of ƒ{2q = ƒ{5.00 nC is located at the origin. (a) Sketch the electric potential verses x for points on the x-axis in the range -1.50 m < x < 1.50 m. (b) Find a
81. ## Urgent!!! Physics

At an air show, a jet plane has velocity components Vx = 625 and Vy = 415 at time 3.85s and Vx = 838 and Vy = 365 at time 6.52s . A. For this time interval, find the x component of the plane's average acceleration in km/h2. B. For this time interval, find
82. ## URGENT! Physics

A boy shoves his stuffed toy zebra down a friction-less chute, starting at a height of 1.07 m above the bottom of the chute and with an initial speed of 1.87 m/s. The toy animal emerges horizontally from the bottom of the chute and continues sliding along
83. ## MATH URGENT!

Ok I don't understand how to find similar figures when using proportions. Can someone explain it to me? Two figures that have the same shape are said to be similar. When two figures are similar, the ratios of the lengths of their corresponding sides are

(I have no idea how to even approach this question. Can anyone please help me?) Some people have proposed that the earth could solve its population problem by shipping people off to space colonies, each containing about 10,000 people. Assuming that we
85. ## Microeconomics help please (urgent)

True or False? Explain your reasoning. a. The short-run average total cost can never be less than the long-run average total cost. b. The short-run average variable cost can never be less than the long-run average total cost. c. In the long run, choosing a

1.Graph the polar equation r=3-2sin(theta) 2. Find the polar coordinates of 6 radical 3,6 for r > 0. 3. Find the rectangular coordinates of (7, 30°). 4. Write the rectangular equation in polar form. (x – 4)2 + y2 = 16 5. Write the equation –2x + 6y
87. ## math

500 students sat for an examination in mathematics,physics and chemistry.45 passed all the three subject,60 passed mathematics and chemistry,70 passed physics and chemistry,50 passed mathematics and chemistry,10 passed in mathematics,80 passed in chemistry

89. ## chemistry

what is the purpose of using an ice bath in organic chemistry when isolating the final product?
90. ## chemistry

Hi I am in AP Chemistry and I did not take regulars chem so I have never done labs before and was wondering If anyone could give me examples on how to do a lab
91. ## Academic 4-year plan: Zoology

Can you take AP Chemistry without taking any previous chemistry class?
92. ## chemistry

answers to latenite labs chemistry lab#9 stoichiometry by loss of CO2
93. ## Chemistry

Why a model of the atom is crucial to understanding chemistry and in explaining the behavior of matter?
94. ## chemistry .............chemistry

what color emission would you see if you heated each solution to an extremely high temperature? why

5. A 1,600 kg car is moving south at 24 m/s. What is its momentum? (Points : 1) 66 kgm/s south 66 kgm/s north 38,000 kgm/s north 38,000 kgm/s south Question 6. 6. The velocity of a 150 kg cart changes from 6.0 m/s to 14.0 m/s. What is the magnitude of the
96. ## VERY URGENT MATH~!!!!!!!!

1. 2(x – 3) = 2x (1 point) one solution no solutions infinitely many solutions 2. 3(y – 3) = 2y – 9 + y (1 point) one solution no solutions infinitely many solutions 3. 10x – 2 – 6x = 3x – 2 + x (1 point) one solution no solutions infinitely
97. ## chemistry

where would you find calcium carbonate and sodium chloride outside a chemistry lab?
98. ## To all chemistry students

Please understand that one of our chemistry tutors is on vacation this week. Please be patient.
99. ## chemistry

Is Procion Red Dye a suitable model for chemistry lab?
100. ## chemistry

where would you find iron II oxide and sodium hydrogencarbonate outside a chemistry lab?