When substances go through chemical changes, which of the following will always happen? a. one or more substances with different chemical properties will form. b. one or more substances will be completely destroyed. c. a poisonous gas will form or a white solid will precipitate. d. all of these

A.  One or more substances with different chemical properties will form.

Explanation:

Chemical change is defined as a change in which rearrangement of atoms take place and leads to formation of new substance. Thus as new substances are formed, the chemical properties of the products will alwys be different from the chemical properties of reactants.

Physical change is defined as a change in which change in shape, size or state of the substance takes place. No new substance is formed.

Chemical change may involve following changes:

1) Formation of precipitates

2) Absorption or evolution of heat

3) Color change

4) Evolution of gas

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: