Calcium oxide or quicklime (cao) is used in steelmaking, cement manufacture, and pollution control. it is prepared by the thermal decomposition of calcium carbonate: caco3(s) → cao(s) + co2(g) calculate the yearly release of co2 (in kg) to the atmosphere if the annual production of cao in the united states is 2.1 × 10^10 kg.

the dependant variable is spilled water

the independent is the heat

the answer is na (sodium)

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.