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1. Accounting for the change in concentration due to dilution is a critical aspe

ID: 943989 • Letter: 1

Question

1. Accounting for the change in concentration due to dilution is a critical aspect of this experiment. Calculate the concentration of the I- ions in a solution if 6.0 mL of 0.30 M KI is added to 4.0 mL of 0.45 M NaI and 2.0 mL of water.

2. A student performing this experiment ended up with an equation of y = -5694x+ 15.32. Using this information and the Rate Law above determine the time it would take for a mixture of 20.0mL of 0.10M H2O2 , 20.0mL of 0.20M KI , 10.0 mL of Buffer, 10.0mL of 0.020M Na2S2O3 with 40.0 mL DI water. How many seconds would it take for the color to change at if the reaction is run at a temperature of 10.0C. Report your answer in seconds

Use the Rate Law of Rate = k'[I-]1[H2O2]1

Explanation / Answer

Moles of I in 6.0 mL of 0.30 M KI = Molarity x Volume (in L)

= 0.30 x 6 x 10^-3

= 1.8 x 10^-3 moles.

Moles of I in 4.0 mL of 0.45 M NaI = Molarity x Volume (in L)

= 0.45 x 4.0 x 10^-3

= 1.8 x 10^-3 moles

Total moles = 3.6 x 10^-3 moles of I

Total volume = 6.0 mL + 4.0 mL + 2.0 mL = 12.0 mL = 0.012 L

Cocentration = 3.6 x 10^-3 moles / 0.012 L = 0.3 M