When planning a simple experiment, what does it mean to “test one variable”? a During the experiment, the scientist keeps the control the same but changes many other elements he or she is testing.

b During the experiment, the scientist has only one element, or variable, that is changed to test the hypothesis.

c The scientist can only use simple language and materials when planning the one variable to be tested.

d The scientist plans and performs just one science experiment a day to test one variable.

If 200.0g of copper(ll) sulfate react with an excess of zinc metal, what is the theoretical yield of copper

Consider this initial-rate data at a certain temperature for the reaction described by

The characteristics 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 an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.