Question

Burning magnesium ribbon in the air to form magnesium oxide is an example of ______ (combination/decomposition) reaction.

Answer 1

Focus on the word combustion and what happens in combustion. Energy is released in this reaction which makes it an exothermic reaction.

Complete step by step answer:
Let’s start with discussing about the reaction that happens when we burn the magnesium ribbon in the air, the reaction is given below:
${\text{2Mg(s) + }}{{\text{O}}_{\text{2}}}{\text{ }} \to {\text{ 2MgO(s) + energy}}$
As we can see when magnesium ribbon is burned in the air the compound formed is ${\text{MgO}}$ that is magnesium oxide. Magnesium oxide is having a solid white colour and during burning energy is released in the form of heat and light. The reason for this energy is the combustion that we provide to the magnesium ribbon. Magnesium oxide has a heat of formation of around $- 601.83$ KJ/mol.
Since energy is being released this means that the reaction is exothermic in nature.
Since, in this reaction $2$ electrons of magnesium are being given to magnesium for the formation of Magnesium Oxide $\left( {{\text{MgO}}} \right)$. This means that this reaction is also a Combination reaction.
Hence the answer to this question is Combination Reaction
$\therefore$ Burning magnesium ribbon in the air to form magnesium oxide is an example of combination reaction

Note:
Basically, Magnesium ribbon is majorly used to explain the students' reaction. A reaction is a phenomenon in which one substance changes from one form to another due to chemical changes. Some reactions may release some energy whereas some energy absorbs the energy from the atmosphere.