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# Acid and Base watch

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1. A typical vitamin C tablet (containing pure ascorbic acid, H2C6H6O6) weighs 500 mg. One vitamin C tablet is dissolved in enough water to make 200.0 mL of solution. Calculate the pH of this solution. Ascorbic acid is a diprotic acid.
2. (Original post by Hemashini)
A typical vitamin C tablet (containing pure ascorbic acid, H2C6H6O6) weighs 500 mg. One vitamin C tablet is dissolved in enough water to make 200.0 mL of solution. Calculate the pH of this solution. Ascorbic acid is a diprotic acid.
What have you done so far? Or rather, how do you think you should tackle this question?
3. pH = -log[H+]

so we need to find the conc of H+ ions in the solution
moles of acid = mass/ Mr = 0.5g / (176) = 0.00284 moles
ascorbic acid is diprotic meaning it releases 2 protons
so moles of H+ = 0.00284*2 = 0.00568

and then you use the equation

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Updated: January 27, 2016
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