What made Mendeleev certain that he should leave gaps in his table?

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

In one or two grammatically correct sentences, write a definition for the term molecule geometry

Heat energy, carbon dioxide, and water are released through which process? a. photosynthesis b. depolymerization c. digestion d. cellular respiration