An Insulator.
Insulators prevent flow of electric current. Example is wood, clay.
Answer: The reaction is exothermic reaction as the energy of products is less than the energy of reactants.
Explanation: Exothermic reactions are defined as the reactions in which energy of the product is less than the energy of the reactants. The total energy is released in the form of heat and
for the reaction comes out to be negative.
Labeling of the parts in the diagram:
A represents the activation energy which is the energy required by reactants to cross the energy barrier to get converted to products.
E represents the potential energy of the reactants.
B represents the activated complex.
D represents the potential energy of the products.
C represents the total enthalpy change of the reaction, which comes out to be negative for exothermic reactions.

I think it’s to long to fit in a period??
The products for the complete combustion of a hydrocarbon in excess air is carbon dioxide and water. Any hydrocarbon when reacted with oxygen will always yield the said products. Incomplete combustion, on the other hand, yields carbon monoxide and water.