The iodine-131 radioisotope is most commonly used to:
detect thyroid problems in people
date fossils from organisms that once lived a very long time ago
measure the amount of radiation in an area
treat cancer in patients

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead

When balancing a chemical equation:

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.