Michael tells Sara he weighs 104 pounds. Sara says she is 44 kilograms. who is heavier?

Compare and contrast physical changes with chemical changes.

How does the motion of particles in a gas change as the gas cools

Some liquids can be distilled, but only at temperatures that are so high that it is impractical, or so high the compound decomposes. explain why distillation such compounds at significantly less than atmospheric pressure (some degree of vacuum) would solve this problem.