A system in which matter may flow in and out, as opposed to a closed system in which matter may not flow in or out.​

Which is mostly likely why many scientists reject the cold fusion theory

Afamily is one another name for a group on the table of elements.

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.