Besides oxygen and hydrogen, which element is most abundant within the human body? iodine (i) boron
b. nitrogen (n) carbon
c.

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.