You do an experiment and want to determine if the chemical reaction is endothermic or exothermic. What can you measure to make that determination? A. Mass
B. Weight
C. Temperature

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

Particles vibrate in a rigid structure and do not move relative to their neighbors.

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.