Calcium carbonate is a compound that is used to make chalk for drawing on rocks or pavement. one molecule has one atom of calcium (ca), one atom of carbon (c), and three atoms of oxygen (o). which is the correct way to write the chemical formula for calcium carbonate? a. 3caco b. ca3co c. caco3 d. ca3c3o3

How can a scientist assess whether a pure niobium (nb) sample is responsible for contaminating the lab with radioactivity? test the niobium sample to see whether it now contains other elements.test the niobium sample for the presence of niobium oxide compounds.heat the niobium, and see if the level of radioactivity in the lab increases.place the niobium under pressure, and see if the level of radioactivity in the lab increases.