Dec 14, 2009
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If 50 mL of H2SO4 required 50.0 mL of 1.0 M NaOH for a complete neutralization reaction, according to the equation shown below. What would be the molarity of an acid?

2NaOH + H2SO4 -> Na2SO4 + 2 H2O

correct answer is 0.5

Please explain me to support your answer. Thank you
 

UndergradGuy7

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Jun 23, 2007
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If 50 mL of H2SO4 required 50.0 mL of 1.0 M NaOH for a complete neutralization reaction, according to the equation shown below. What would be the molarity of an acid?

2NaOH + H2SO4 -> Na2SO4 + 2 H2O

correct answer is 0.5

Please explain me to support your answer. Thank you
50mL NaOH * 1.0 M of NaOH = 50 millimoles (or 0.050 moles of NaOH). In the equation NaOH reacts with H2SO4 in a two to one ratio. So 50 millimole * (1 H2SO4/2 NaOH) = 25 millimoles of h2so4.

Molarity = moles / volume so 25 millimoles / 50 milliters = 0.5 M


Even if they did not give you the equation. From h2so4 you should see and know that it has 2 h+. So it will take twice as much NaOH to neutralize it. Or if you use the same volume then the concentration is twice as high etc.
 

dentalWorks

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Jun 25, 2009
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50mL NaOH * 1.0 M of NaOH = 50 millimoles (or 0.050 moles of NaOH). In the equation NaOH reacts with H2SO4 in a two to one ratio. So 50 millimole * (1 H2SO4/2 NaOH) = 25 millimoles of h2so4.

Molarity = moles / volume so 25 millimoles / 50 milliters = 0.5 M


Even if they did not give you the equation. From h2so4 you should see and know that it has 2 h+. So it will take twice as much NaOH to neutralize it. Or if you use the same volume then the concentration is twice as high etc.
I was about to do it until I saw this :thumbup: