Plz need fast what is the name of the theory that sciencetist have developed to explain the formaton of the universe

a. plate tectonics
b. big bang
c. continental drift
d. black hole

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.

Does the energy in a solid increase or decrease when changing to a liquid?

Asolution of sodium hydroxide was titrated against a solution of sulfuric acid. how many moles of sodium hydroxide would react with 1 mole of sulfuric acid?