What is the equilibrium constant of a reaction? This isn't a question but a answer to a question I couldn't find the answer to :)

"What is the equilibrium constant of a reaction?"

A) It is the ratio of the concentrations of products to the concentrations of reactants.

B) It is the number of moles of reactants subtracted from the number of moles of products.

C) It is the ratio of the number of moles of products to the number

of moles of reactants.

D) It is the concentrations of products multiplied by the concentrations of reactants.

THE ANSWERS A!! Hope this helps sum ppl :)

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.