Question

give the example of a combination reaction which is also an exothermic reaction.

Answer 1

In a combination reaction the atoms and/or molecules do what the name implies: they combine to form the product. Combination reactions are always exothermic. For example barium metal and fluorine gas will combine in a highly exothermic reaction to form the salt barium fluoride:

Ba + F2 ----> BaF2

Another example is given by magnesium oxide combining with carbon dioxide:

MgO + CO2 ----> MgCO3

Often, reaction can fall into more than one category. For example the combustion of magnesium metal is also a combination reaction:

2Mg + O2 ----> 2MgO + Heat.

Thank you.