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3 years ago

5

A buret is used to dispense standardized NaOH solution. The initial buret reading is 2.73 mL, and after dispensing a known volum

e of NaOH the buret reading is 15.67 mL. If the concentration of the NaOH is 0.125 M, how many moles of NaOH were dispensed

1 answer:

Novosadov [1.4K]3 years ago

3 0

Answer:

1.62x10⁻³ moles of NaOH were dispensed

Explanation:

Molarity is an unit in chemistry defined as the ratio between moles of solute (In the problem, NaOH), per liter of solution.

The concentration of the solution is 0.125moles per liter. That means 1L of solution has 0.125 moles of NaOH.

The volume you dispensed in the buret was:

15.67mL - 2.73mL =

12.94mL of the 0.125M NaOH are:

12.94mL = 0.01294L * (0.125moles / L) =

<h3>1.62x10⁻³ moles of NaOH were dispensed</h3>

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$0.241 mole\times 74.55 g/mol\times 2 = 35.93 g$

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