In the laboratory, a general chemistry student measured the pH of a 0.441 M aqueous solution of pyridine, C5H5N to be 9.394. Use the information she obtained to determine the Kb for this base. Kb(experiment) =

Help with the following question. Please round the answer to 2 sig figs

Calculate the pH that results when 2.35 mL of a 0.0125 M aqueous solution of KOH is added to 23.50 mL of an 0.0132 M aqueous solution of methylamine (CH3NH2, Kb = 4.2 x 10–4). Show your work and justify any approximations made.

A weak base has a Kb = 1.5 x 109. What is the value of the pKa for the conjugate acid? Enter your answer, rounded to the correct number of significant figures, into the box below. Do not use scientific notation. If your answer is a decimal, please include a 0 before the decimal point. pka = type your answer...

In the laboratory, a general chemistry student measured the pH of a 0.386 M aqueous solution of nitrous acid to be 1.865. Use the information she obtained to determine the Ka for this acid. Ka(experiment) = In the laboratory, a general chemistry student measured the pH of a 0.431 M aqueous solution of hydrofluoric acid to be 1.741. Use the information she obtained to determine the Ka for this acid. Ka(experiment) =

The pH scale depends on the value of Kw. What would the pH of neutral water be if the Kw was 5.54 x10-15? IMPORTANT: When entering your answer: •Enter the number only (no units) • Do not leave any spaces Use a leading zero before the decimal when necessary Report your number to 3 decimal places (regardless of the significant figures) • Correctly round your answer to the 3rd decimal place (allowed margin of error is only ± 0.001, so always use un- rounded numbers in your calculations) Examples: 0.123 or 9.876

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Initial pH: 10.18 Kb: 5.13x10^-5

Calculate the pH of 0.550 M acetic acid, Ka = 1.80 x 10–5.  Provide your answer to three decimal places. Do not enter units.

Some measurements of the initial rate of a certain reaction are given in the table below. N2 H2 initial rate of reaction 0.849 M 1.92 M 88.0 M/s 0.849 M 4.04 M 390. M/s 0.359 M 1.92 M 15.7 M/s Use this information to write a rate law for this reaction, and calculate the value of the rate constant k. Round your value for the rate constant to 3 significant digits. Also be sure your answer has the correct unit symbol. rate - k0 k = 0 ?