Recent content by dnt

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    A point moves along the curve y=2x^2+1

    A point moves along the curve y=2x^2+1 in such a way that the y value is decreasing at the rate of 2 units per second. At what rate is x changing when x=(3/2)?Ok here's what I've done... Dy/dt=(4x)(dx/dt) -2 = (4*3/2)(dx/dt) So dx/dt=-1/3 (ie decreasing by 1/3 units per second) First, is...
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    Question on the logic of rational roots theorem

    i see - thanks for the help everyone! makes sense. i did get complex confused with irrational.
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    Question on the logic of rational roots theorem

    this is not a homework question, but rather I feel like there is a contradiction in the theorem and just want clarity. I know the theorem is correct so I am looking for help in where the mistake is in my logic. take f(x) = x^3 + x^2 - 4x- 7 the rational roots theorem says if there are any...
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    Can you have a triple replacement reaction?

    thank you for the reply. just to add to the question, hypothetically if you add NaCl and KOH you should get NaOH and KCl, right? but then if you add a 3rd reactant (say Ca(NO3)2) why doesn't it then continue to react with the NaOH and KCl that have now been created from the first reaction...
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    Can you have a triple replacement reaction?

    is it possible to have a triple replacement type reaction? I know of single and double replacement but what if you mix sodium carbonate, magnesium hydroxide, and potassium sulfate all together (this is all made up just for an example). would all the different ions mix to form all possible...
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    Le chatliers principle and solids

    im pretty sure i know the answer but want to be sure. if you have a reaction such as : A(g) + B(g) --> C(g) + D(s) and you increase the concentration of A, the reaction will shift to the right. and i know the concentration of B will decrease and C will increase. but what about D. I am...
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    Free body diagram (centripetal force)

    but i thought the sum of all the forces has to equal the net force (ie, centripetal force) - how come on my diagram those force vectors don't add up to the centripetal force vector?
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    Free body diagram (centripetal force)

    yes but then how do those add up to the centripetal force? on the diagram it doesn't add up
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    Free body diagram (centripetal force)

    forces vertically would be weight and normal i think. im trying to draw my diagram from a birds eye view. and i can't figure out which way friction would point or if there is another force too. my logic is that if there is a forward force (engine force?) there would have to be at least one...
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    Free body diagram (centripetal force)

    Homework Statement simple question really - how do you draw the free body diagram for a car going around a corner? Homework Equations n/a The Attempt at a Solution i know the net force, the centripetal force, points towards the middle. i have an engine force pointing tangentally...
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    Determining OH- and pH of a weak base

    the question is simply to determine the [OH-] and pH of a solution that is .210 M in HCO3- first of all if i can get [OH-] then i can easily get pH by converting [OH-] to [H+] and then doing the -log[H+] so that part is easy. i just cannot get [OH-] what i did was first write the...
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    Calculating concentrations

    question states: Calculate the concentration of all species in a 0.240 M C6H5NH3Cl solution. first of all how do i know what the reaction is? secondly to i need to know the Ka value for the dIssaciation for this - why isn't it given?
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    What is the relationship between Kc and Kp?

    bump: found one correction i think: for A: I=0, C=x, E=x for B: I=2, C=-2x, E=2-2x but still cannot connect these values (which are pressures) to a given Kc value without temperature. what should i try next?
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    Determining intial rates of reaction

    i think i solved it: rate = k[C2H5Br ][OH] correct?
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    How to find equilibrium pressure when volume changes

    where did you get K = 5.33? and is that Kp or Kc? and why isn't Peq for NO2 = 1.2 + 2x? where did the 1.2 go? thanks for all your help.
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