How does atomic radius relate to atomic structure?

Balance the following reaction. as2s3 + 9o2 → 2as2o3 + so2

The semi-conductors on the periodic table are classified as

Two liquids are poured into a beaker. after a few seconds, the beaker becomes warm. which of the following best describes this reaction? a. an exothermic reaction b. a decomposition reaction c. an endothermic reaction d. a single-displacement reaction