Which changes occur when pt2+ is reduced?
(1) the pt2+ gains electrons and its oxidation number increases.
(2) the pt2+ gains electrons and its oxidation number decreases.
(3) the pt2+ loses electrons and its oxidation number increases.
(4) the pt2+ loses electrons and its oxidation number decreases.

Which best describes how johannes kepler developed his laws of planetary motion

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.

Nonpoint source pollution is difficult to control because it