A heterogeneous mixture where the particles of a material are spread though a liquid or gas not are too large to stay mixed without being stirred or shaken - particles will settle.

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

The time that is taken by neptune once around the sun is called

In which phase of mitosis do the spindle fibers pull the chromosomes apart to opposite sides of the cell ?