Recent content by sam.

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    Organic Chem: Energy Barriers to Rotation

    I have a lab question that I'm stuck on. For your assigned molecule evaluate the energy barrriers to the rotation: from anti to gauche from gauche to gauche from gauche to anti I have data/graph of steric energy vs. dihedral angle of 1-chloropropane, but I don't know how to use...
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    Does Sodium Benzoate React When Mixed with Water and Different Solutions?

    Would sodium benzoate react (dissolve) when added to water and HCl, or to water and NaOH? Also, how would you write the chemical equations for the reactions?
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    Where are the points?Where are the points?

    Homework Statement A 10.0 nC charge is located at position (x, y) = (1.0 cm, 2.0 cm). At what (x, y) position(s) is the electric field a. -225,000i N/C b. (161,000i + 80,500j) N/C c. (28,800i + 21,600j) N/C Homework Equations E = (1/4\pi\epsilon)(q/r^2) F = Kq_1q_2/r^2 The...
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    Calculating Tune Adjustment for Flutist's Note A: Aa Flutist in 342 m/s Room

    1. Homework Statement Aa flutists assembles her flute in a room where the speed of sound is 342 m/s. When she plays the note A, it is in perfect tune with a 440 Hz tuning fork. After a few minutes, the air inside her flute has warmed to where the speed of sound is 346 m/s. A) How many beats...
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    Calculating Beats and Extension for a Flutist in Perfect Tune - Flute Homework"

    Homework Statement Aa flutists assembles her flute in a room where the speed of sound is 342 m/s. When she plays the note A, it is in perfect tune with a 440 Hz tuning fork. After a few minutes, the air inside her flute has warmed to where the speed of sound is 346 m/s. A) How many beats...
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    Chemistry - Adding Strong Acid to Buffer

    Homework Statement A beaker with 135 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.1 M. A student adds 7.80 mL of a 0.400 M solution to the beaker. How much will the pH change? The pKa of acetic acid...
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    Question: Adding Strong Acid to Buffer

    A beaker with 135 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.1 M. A student adds 7.80 mL of a 0.400 M solution to the beaker. How much will the pH change? The pKa of acetic acid is 4.76. What I did...
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    How Does Adding Sodium Citrate Affect the pH of a Citric Acid Solution?

    What is the pH change of a 0.270 M solution of citric acid (pKa = 4.77) if enough sodium citrate is added to make the final concentration of the common citrate ion 0.145 M? Okay so first I did an ice-table using the equation: citric acid + water <--> hydronium + citric ion Using an inital...
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    Activation energy of a certain reaction

    The activation energy of a certain reaction is 45.8 kJ/mol. At 20 degrees celsius, the rate constant is 0.0130 s^(-1). At what temperature would this reaction go twice as fast? Arrhenius Equation:k = Ae^(-E_a/RT) ln(k_2 / k_1) = (E_a /R)(1/T_1 - 1/T_2) Okay, so I'm not quite sure how...
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    Freezing Point Depression and Ethylene glycol

    Homework Statement Ethylene glycol, the primary ingredient in antifreeze, has the chemical formula C_2H_6O_2. The radiator fluid used in most cars is a half-and-half mixture of water and antifreeze. What is the freezing point of radiator fluid that is 50% antifreeze by mass? K_f for water...
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    Collision of B1 & B2: Solving the Homework Statement

    Homework Statement Ball 1 (B1) and Ball 2 (B2) are located at (x,y)=(0,0) and (x,y)=(d,h). At t=0, B1 is sent towards the initial location of B2 with a speed vi. At the same instant that B1 is launched, B2 falls towards the ground with zero initial velocity. Assume there is no air...
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    Chemistry - Gas Law Stiochiometry

    Homework Statement Acetylene torches are used for welding. These torches use a mixture of acetylene gas, C_2H_2, and oxygen gas, O_2 to produce the following combustion reaction: 2C_2H_2(g) + 5O_2(g) --> 4CO_2(g) + 2H_2O(g) Imagine that you have a 6.50 L gas tank and a 4.50 L gas...
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    Which Gas Behaves Most Ideally: N2, CO, or H2?

    Homework Statement In general, which of the following gases would you expect to behave the most ideally? a) N_2 b) CO c) H_2 Homework Equations N/A The Attempt at a Solution Okay, so I know that CO would definitely not behave the most ideally. I tried looking this up on the...
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    Help on Uniform Circular Motion Problem Please

    Homework Statement 1. Homework Statement Derive a formula for the bullet speed v in terms of D, T, and a measured angle between the position of the hole in the first disk and that of the hole in the second. If required, use \pi, not its numeric equivalent. Both of the holes lie at the...
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    Chemistry Help - Using the Gas Laws

    Homework Statement This figure (file attached) shows a container that is sealed at the top by a movable piston. Inside the container is a ideal gas at 1.00 atm, 20.0 degrees Celsius, and 1.00 L. The gas sample has now returned to its original state of 1.00 atm, 20.0 degrees Celsius and...
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