This graph shows the energy involved in a reaction involving two molecules. Describe what is happening or what the state of the reaction is at A, B, C, and D. Then tell if this is an exothermic or an endothermic reaction.

What does standard deviation reveal about data? a. the average of all the data points b. which of the data points is most reliable c. how spread out the data points are d. the percent error included in the data

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.