The mass of a jar and lid with white marbles and black marbles is 1,500 grams. the mass of the marbles alone 1/2 the total mass of the jar, lid, and marbles. what is the difference between the mass of the jar with the marbles and the total mass of only the marbles?

pure water does not conduct electricity very well. however, when certain substances are dissolved in water, the solution does conduct electricity. you can make a simple device that shows how well a solution conducts electricity. this device uses a flashlight bulb to indicate how well the solution conducts electricity. the better the solution conducts electricity, the brighter the bulb will glow.

explanation:

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.