The law of superposition states that
a. older material is located on top of younger material
b. older material is located next to younger material
c. older material is located below younger material
d. it is impossible to tell which material is older or younger

Write the formula for the following chemicals. 7. e. trinitrogen tetraoxide a calcium phosphate f. magnesium acetate b. potassium sulfide g nickel(iii) cyanide c carbon dioxide h. silver sulfate d. cobalt(ii) chloride

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.

The atomic number, or number, is the described as the number of in the nucleus of an chemical element.