Suppose in an experiment to determine the amount of sodium hypochlorite in bleach, 0.0000538 mo KIO3 were titrated with an unknown solution of Na2S2O3 and the endpoint was reached after 17.80 mL. How many moles of Na2S2O3 did this require?

3.228x10⁻⁴ moles of Na2S2O3 are required

Explanation:

In iodometry, the reaction of KIO3 with Na2S2O3 is:

KIO3 + 6 Na2S2O3 + 6H⁺ → KI + 3Na2S4O6 + 3H2O + 6Na⁺

Where 6 moles of Na2S2O3 reacts per moles of KIO3.

The moles of Na2S2O3 required to reach endpoint when 0.0000538 moles of KIO3 are:

0.0000538 moles of KIO3 * (6 moles Na2S2O3 / 1 mol KIO3) =

relative humidity is a measure of the amount of moisture in the air relative to the total amount of moisture the air can hold.

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