Is CO32- a product, reactant, or coefficient

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world

The biomedical technique in which a part of the brain is destroyed with electric current is known as a. electroconvulsive therapy b. prefrontal lobotomy c. bilateral cingulotomy d. tardive dyskinesia

Two solids are mixed in a flask and stirred. after a few minutes, the flask becomes cold. which of the following best describes this reaction? a. an exothermic reaction b. a combustion reaction c. an endothermic reaction d. a decomposition reaction