3science questions! i'm stuck on my last 3.
#1 compare and contrast chemical change and physical change.
#2 compare and contrast a gas and a plasma.
#3 what state of matter has the electrons separated from the nuclei of the atoms?
gas
solid
liquid
plasma

Which statement best describes the oxidation numbers of the atoms found in magnesium chloride? a. magnesium has a 2- oxidation number and chlorine has a 1+ oxidation number. b. magnesium has a 2- oxidation number and chlorine has a 2+ oxidation number. c. magnesium has a 2+ oxidation number and chlorine has a 1- oxidation number. d. magnesium has a 1+ oxidation number and chlorine has a 1- oxidation number.

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.