A chemist titrates 60.0mL of a 0.2821M hydrocyanic acid HCN solution with 0.3023M NaOH solution at 25°C. Calculate the pH at equivalence. The pKa of hydrocyanic acid is 9.21. Round your answer to 2 decimal places.

Note for advanced students: you may assume the total volume of the solution equals the initial volume plus the volume of NaOH solution added.

Darla claims that the first periodic table developed by mendeleev was not completely accurate, so it is not useful at all. harmony argues that it establish the periodic table we use today, making it more credible. who is correct and why? darla is correct, because a model that has any mistakes should be thrown out. darla is correct, because a good model would not need to change. harmony is correct, because mendeleev’s model had all of the information correct in the first version. harmony is correct, because mendeleev’s model made predictions that came true.

An object becomes electrically charged when: electrons are created in it electrons from it are destroyed electrons are transferred to it protons from it are destroyed protons are created in it

Consider the reaction of a(g) + b(g) + c(g) => d(g) for which the following data were obtained: experiment initial [a], mol/l initial [b], mol/l initial [c], mol/l initial rate, mol/l.s 1 0.0500 0.0500 0.0100 6.25 x 10^-3 2 0.100 0.0500 0.0100 2.50 x 10^-2 3 0.100 0.100 0.0100 1.00 x 10^-1 4 0.0500 0.0500 0.0200 6.25 x 10^-3 what is the rate law for the reaction?