Ethane (CH) is one of many compounds that burns in oxygen to form carbon dioxide and water, as represented by the equation. 2C2H6 + 702 4CO2 + 6H2O
Which substance is a product in this reaction?

carbon dioxide and water.

Explanation:

Chemical equation:

2C₂H₆ + 7O₂      →    4CO₂ + 6H₂O

Reactants are present on the left side of chemical equation while products are present on the right side of chemical equation. In given chemical equation ethane and oxygen are reactant while carbon dioxide and water are product.

The given reaction is combustion reaction. Ethane is burnt in the presence of oxygen and produces carbon dioxide and water.

The reaction also follow the law of conservation of mass.

This law was given by French chemist  Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

the answer is na (sodium)