Answer:
Explanation: in exothermic reaction heat is released out
In endothermic reaction heat is absorbed
Carbon is located in the fourth group, second period. It is also in the nonmetal section of the table as well
Copper is the answer to ur question
2HCO3 - + Ca2+ CaCO3 + CO2 + H2O Bicarbonate (HCO3-) combines with calcium ions in the water to make calcium carbonate (CaCO3, limestone). This process can occur both within organisms such as corals or as a simple chemical reaction in the water itself.