The chart seen here shows the decay of a sample of carbon-14 over a period of 33,000 years. what is the approximate half-life of carbon 14?

10-14. (a) when 100.0 ml of weak acid ha were titrated with 0.093 81 m naoh, 27.63 ml were required to reach the equivalence point. find the molarity of ha. (b) what is the formal concentration of a- at the equivalence point? (c) the ph at the equivalence point was 10.99. find pk. for ha. (d) what was the ph when only 19.47 ml of naoh had been added?

List four observations that indicate that a chemical reaction may be taking place

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins