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  1. E

    Gen Chem - Isomers in a complex ion

    How can you know if a complex ion has an optical isomer or not? I understand that it's when the mirror image can't be superimposed but am having trouble recognizing it. For example, take [Co(NH3)4F2]+. Does this have an optical isomer or just cis/trans?
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    Rigid Objects in equilibirum

    A 1200 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A W = 1960 N crate hangs from the far end of the beam. Picture: http://edugen.wiley.com/edugen/courses/crs1507/art/qb/qu/c09/ch09p_20.gif Calculate the magnitude of the tension in the...
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    Calculating Ksp from Delta H

    Is it possible to calculate Ksp at a certain temperature if you know Ksp at a different temperature and \Delta H?
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    Calculating free energy from Ksp

    Okay so I'm confused. In my book it says that ksp for Ca(OH)2 = 6.5E-6 and \Delta G=-898.5 yet when I use the equation \Delta G=-RTln(Ksp) the value I get is 29.59KJ/mol. I used R=8.314 and T=298K. What's up with that? Thanks.
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    Analysis of simple salt

    What is the color of solid silver phosphate? I don't have a reference book handy with me. Thanks.
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    Force/vectors problem

    http://imageshack.us" [Broken] http://g.imageshack.us/img10/scan0001px3.jpg/1/" [Broken] http://g.imageshack.us/img27/scan0001xe4.jpg/1/" [Broken] Well I just set the sum of x and y components equal to 0 and got: force 3 = -65N in x and 43.3N in y which gave me a magnitude of 78.1 N and...
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    Graphing a circle

    Consider x^2 + y^2 – x + 2y + 1 = 0. (a) Find the coordinates of the center and the length of the radius. (b) Determine the coordinates of the intercepts. (c) Graph the circle. I'm really lost on this one. I tried plugging in numbers but I seriously doubt that's how I'm supposed to do...
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    Partial Fractions prob

    \int e^{ax}cosbx This one is driving me insane. So I used e^ax as u and cosbx dx as dv. And then I did it again using e^ax as u and sinbx as dv which left me with \int e^{ax}cosbx = \frac{1}{b}e^{ax}sinbx + \frac{a}{b^{2}}e^{ax}cosbx - \frac{a^{2}}{b^{2}}\int e^{ax}cosbxdx I have no...
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    Work and Mass problem

    1. A great conical mound of height h is built. If the workers simply heap up uniform material found at ground level, and if the total weight of the finished mound is M, show that the work they do is .25hM So I related weight density to mass by using volume of a cone and got w =...
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    Washer method problem

    1. Find the volume generated by revolving the area bounded by x=y^{2} and x=4 about the line y=2. Is it \pi\int(4-(2-\sqrt{x})^{2}dx from 0 to 4?
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    Integration help

    The loop 9y^2=x(3-x)^2 is revolved about the y-axis. Find the area of the surface generated this way. I just need help with integration: 4\pi\int x\sqrt{\frac{x^{2}+2x+1}{4x}} I know I can pull out the 4 but after that I'm lost. Any suggestions?
  12. E

    Volume by Cylindrical Shells (need verification)

    A hole of radius \sqrt{3} is bored through the center of a sphere of radius 2. Find the volume removed 4\pi\int\intx\sqrt{a^{2}-x^{2}}dx from \sqrt{3} to 2\sqrt{3}? And then subtract this from the volume of the sphere?
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    Volumes: The Disk Method

    Volumes: The Disk Method [Resolved] 1. If the area bounded by the parabola y = H - (H/R^{2})x^{2} and the x-axis is revolved about the y-axis, the resulting bullet-shaped solid is a segment of a paraboloid of revolition with height H and radius of base R. Show its volume is half the volume of...
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    Related rates prob.

    Related rates prob. [solved] A hemispherical bowl of radius 8 in. is being filled with water at a constant rate. If the water level is rising at the rate of 1/3 in./s at the instant when the water is 6 in. deep, find how fast the water is flowing in by using the fact that if V is the volume of...
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    Optimizing surface area of a silo

    A silo has cylindrical wall, a flat circular floor, and a hemispherical top. If the cost of construction per square foot is twice as great for the hemispherical top as for the walls and the floor, find the ratio of the total height to the diameter of the base that minimizes the total cost of...
  16. E

    Applied maximum and minimum problems problem

    Optimization 1. A new branch bank is to have a floor area of 3500 ft^{2}. It is to be a rectangle w/ 3 solid brick walls and a decorative glass front. The glass costs 1.8 times as much as the brick wall per linear foot. What dimensions of the building will minimize cost of materials for the...
  17. E

    Kinetics of Radioactive decay

    1. surface water contains enough tritium to show 5.5 decays events per minute per 100. g of water. Tritium has a half-life of 12.3 years. You are asked to check a vintage wine that is claimed to have been produced in 1946. How many decay events per minute should you expect to observe in 100.g of...
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    Integral question

    Why is the anti derivative of 1/(x-3) equal to -ln\left|x+3\right|. Why isn't it just ln\left|x-3\right|. Does it have something to do with the absolute value? Thanks.
  19. E

    Help with Integration

    1. How would I do this: \int\frac{x^{2} - 1}{x} I don't need the answer, only the method I need to use (integration by parts, partial fractions etc.) Thanks.
  20. E

    Partial Pressure Problem

    1. Assume that two cylinders at 27° C are connected by a closed stopcock(valve) system. The right-hand cylinder contains 2.4L of hydrogen at 0.600 atm; the left cylinder is larger and contains 6.8 L of helium at 1.40 atm. a) How many moles of each gas are present? b) What is the total pressure...
  21. E

    Definite Intergrals applied to area

    1. y=sec^{2}x and y=e^{2x}, in Quadrant I, for x\leq1. I need to calculate the area. 2. fundamental theorem 3. I'm using 0 and 1 as my lower and upper bounds and the answer I'm getting is -1.637 which is not reasonable. When I integrate using the calculator it's coming out to be...
  22. E

    Indefinite integral

    1. \int(x^{2} + 5)^{3}dx This is what the book gives as the answer 1/7x^{7} + 3x^{5} + 25x^{3} + 125x + C I got something way different. Where are they getting the 3x^5 and 25x^3 from? Thanks. -v.b.
  23. E

    Pressure as a function of depth

    1. There is a 16.8 m tall oil-filled barometer. The barometer column is 80.0% filled w/ oil when the column of a mercury barometer has a height of 722mm Hg. If the density of mercury is 1.36 x 10^4 kg/m^3, what is the density of oil? Homework Equations P=Po + pgh D=m/v The Attempt at a...
  24. E

    Snell's Law lake light problem

    1. Depth of a lake is 1637m. If a beam of light with an angle of incidence of 60.0º enters the water from the air, what is the horizontal distance between the point where the light enters the water and the point where it strikes the lake's bottom? 2. Snell's Law: ni(sin Өi) = nr(sin Өr)...
  25. E

    Convex mirrors

    1. The radius of Earth is 6.40 x 10³ km. The moon is about 3.84 x 10^5 km away from Earth and has a diameter of 3475 km. The Pacific Ocean surface, which can be considered a convex mirror, forms a virtual image of the moon. What is the diameter of that image? 2. 1/p + 1/q = 1/f M = h'/h =...
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    Sound Waves

    Who was the first person to measure sound waves and how did he do it. Also how can you measure sound waves with a tuning fork.
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    Rotational Motion

    1. I need some ideas on how to demonstrate angular velocity and angular acceleration in the class. 3. We have some wheels w/ handles on either side that we can use to show rotation. We're going to apply the equations of angular velocity and acceleration to that. Does anyone have any...
  28. E

    Demonstrating angular velocity and accelaration

    1. how would you set up an experiment to show angular velocity and angular accelaration that can be done in a classroom with classroom equipment?
  29. E

    Lab-calculating mass

    If you were give an uknown mass and told to find it's mass w/out using a scale, how would u go about doing it. You have a meter stick, stopwatch, and 2 cars (which you can mass) w/ flat surfaces so you can put the unknown weight on it. I want to use the conservation of momentum in elastic...
  30. E

    Work-kinetic energy theorem

    The CN tower in 553m tall. Suppose a chuck of ice w/ a mass of 25.0g falls from the top of the tower. The speed of the ice is 33.0m/s as it passes the restaurant in the tower located 353m above the ground. What is the average force due to air resistance? I'm having trouble getting started on...
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