Select the correct answer. Which reaction is a decomposition reaction?

A.
2KClO3 → 2KCl + 3O2
B.
4Na + O2 → 2Na2O
C.
ZnS + 3O2 → 2ZnO + 2SO2
D.
2NaBr + CaF2 → 2NaF + CaBr2

Answer asap need to be answered 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.