Please help i just need question 15

The molecular formula for caffeine is cshion402. which of the following elements is not found in caffeine?

According to coulomb's law, how would the electrical force between particles change if the product of their electrical charge increased?

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.