Chem 103 Exam 1Questions & Answers 100% Accurate!

What is chemistry? - ANSWERChemistry is the study of the physical and compositional changes of matter. Chemistry is called the Central Science. Many health related areas of study are based on Chemistry. Matter - ANSWERMatter is anything that has mass, occupies space and is made-up of atoms or parts of atoms. Mass - ANSWER-Mass is a measure of the amount of matter in an object. -Mass is independent of the location of an object. -An object on the earth has the same mass as the same object on the moon, but not same weight. Weight - ANSWER-Weight is a measure of gravitational force acting on object. -Weight depends on the location of an object. -Force = Mass * Acceleration, F = ma, Wt = m(gravity). -An object weighing 1.0 lb on earth, weighs about 0.17 lb on the moon. Mass of object is constant. Moon has 1/6 gravity of earth, which reduces apparent weight of object. Physical Properties of Matter - ANSWER-Physical properties can be observed or measured without changing the composition of the matter being observed. Examples of physical properties are: color, shape and mass, and all changes of state like gas to a liquid. Chemical Properties of Matter - ANSWER-Chemical properties can be observed or measured only when the composition of matter is changed. Examples of chemical properties are flammability and the ability to react (e.g. when vinegar and baking soda are mixed). Atoms must change partners. Physical changes of Matter - ANSWER-Physical changes are reversible. -Physical changes take place without a change in composition. Atoms are not changing partners. -Nothing new is being created.