Which method of testing substances is a sure way to identify a chemical reaction? a. change in color b. formation of bubbles c. change in density d. increase in temperature e. solubility in water

It C. change in density (I WAS INCORRECT ON PLATO TEST IT IS NOT C)

Explanation:

"To definitively determine that a chemical reaction has taken place, it is necessary to carefully test the properties of reactants and products. Each substance has a unique set of properties. One of them is density. We can determine whether two substances are the same or different by calculating and comparing their densities. No two substances in their purest form have the same density." this is from my plato science notes

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.