What is the Ka of a 0.168 M solution of hydrocyanic acid
(HCN) with a pH of 3.15?
Ka = [ ?] 10

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

the answer would be a