More than half of the elements on the periodic table are

Achemistry student weighs out of phosphoric acid , a triprotic acid, into a volumetric flask and dilutes to the mark with distilled water. he plans to titrate the acid with solution. calculate the volume of solution the student will need to add to reach the final equivalence point. round your answer to significant digits.

According to the diagram; a) identify the anode of the cell and write the half-reaction that occurs there b) write the overall equation for the reaction that occurs as the cell operates c) calculate the value of the standard cell potential ,e cell. d)write the shorthand notation of the cell above e)indicate the flow of the electrons on the diagram

What is the value of keq for the reaction expressed in scientific notation?