Assume that you have a sample of acetic acid (pKa=4.75) dissolved in water?

Question

So I've used 3 attempts and I only have one left on this. Here's the 3 parts to the question:

Part A

Draw the structure of the major species present in the water solution.

Part B

Now assume that aqueous HCl is added to the acetic acid solution until pH2 is reached. Draw the structure of the major species present.

Part C

Finally, assume that aqueous NaOH is added to the acetic acid solution until pH12 is reached. Draw the structure of the major species present.

? · Answer

Something happened to the question you just posted (Aug 17, 2016)

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QUESTION:

Evaluate the surface integral (Cylinder between planes)?

http://imgur.com/a/2nhgS (picture of the question)

Evaluate the surface integral.

(double integral S) (z+x^2 y) dS

S is the part of the cylinder y2 + z2 = 16 that lies between the planes x = 0 and x = 6 in the first octant.

I ended up wit 2176pi but that's not the right answer. Thanks to anyone who can help.

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MY ANSWER:

Since we cannot express x as a function of y and z, we'll need to parameterize the cylinder

r(x,θ) = (x, 4cosθ, 4sinθ)
x = 0 to 6
θ = 0 to π/2 (first octant)

∫∫ f(x,y,z) dS = ∫∫ f(r(x,θ)) ||∂r/∂x × ∂r/∂θ|| dA
S　　　　　　　　 D

f(x,y,z) = z+x²y
f(r(x,θ)) = f(x,4cosθ,4sinθ) = 4sinθ + 4x²cosθ
∂r/∂x = (1, 0, 0)
∂r/∂θ = (0, −4sinθ, 4cosθ)
∂r/∂x × ∂r/∂θ = (0, −4cosθ, −4sinθ)
||∂r/∂x × ∂r/∂θ|| = √((−4cosθ)²+(−4sinθ)²) = √16 = 4

∫∫ (z+x²y) dS = ∫ [0 to 6] ∫ [0 to π/2] (4sinθ + 4x²cosθ) * 4 dθdx = 1248
S

skipper · Answer

(1) CH3COOH
(2) CH3COOH
(3) CH3COO^-1

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Assume that you have a sample of acetic acid (pKa=4.75) dissolved in water?

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