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Aka_Selina
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[*] posted on 4-6-2006 at 13:06
HW Question

How many milliliters of 0.150M hydrochloric Acid are required to neutralize 0.250g of diethylamine?? :(
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guy
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[*] posted on 4-6-2006 at 13:25


First write the balanced equation.

Find numer of moles of base.

Then do stoichiometry and find out how much moles of acid you need.

Calculate volume of acid using V = m / M

Convert the Liters to milliliters



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Aka_Selina
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[*] posted on 4-6-2006 at 13:30


HCl + CH3CH2-NH-CH2CH3 --> ??


Is the correct?
I am really confused!! What would the product be??
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guy
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[*] posted on 4-6-2006 at 13:34


HCl + (CH3CH2)2NH ------> (CH3CH)2NH2Cl

[Edited on 6/4/2006 by guy]

[Edited on 6/4/2006 by guy]



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Aka_Selina
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[*] posted on 4-6-2006 at 13:41


Thanks guy for helping...

I think it's suppose to be MaVa = MbVb
but how come M of the base is not given then?
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[*] posted on 4-6-2006 at 14:03


No you're thinking or M1V1 = M2V2 and what that equation trying to say is that the moles of M1V2 is the same as the moles for M2V2. That is used for different problems such as dilution.

For this problem, you find moles of base by using grams/molar mass.



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[*] posted on 4-6-2006 at 14:15


I'm sorry... I know I'm really slow but do you think you can show me exactly how to do that?
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[*] posted on 4-6-2006 at 15:33


Add up the atomic masses of every element in diethylamine. Take 0.250 g and divide it by the molar mass of diethylamine.

So use stoichiometry to find out how much acid you need. It should be the same amount as the base.

Now take the moles of acid / Molarity (0.150M) to get volume.



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[*] posted on 4-6-2006 at 18:14


Okay.

I did .250g C4H11N x 1 mol C4H11N / 106g C4H11N = .002358 mol C4H11N

.002358 mol C4H11N x 1 mol HCl / 1 mol HCl = .002358

.002358 mol HCl / .150 M = .01572 L of HCl


Is this correct?
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[*] posted on 4-6-2006 at 18:20


Yes that is correct. Make sure you convert the answer to mL like the question asked.



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smile.gif posted on 4-6-2006 at 18:22


Yay!! Finally :) Thanks Guy
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