sulfur is a reactant
There is no elemental iron (Fe) involved in this reaction, neither as reactant (iron sulphide -FeS- plus oxygen are) nor as product (iron oxide (FeO) plus sulphur dioxide are)
When sulfur reacts with chlorine to produce disulfur dichloride, the name of the compound corresponds to a chemical formula of S2Cl2, which shows that the same numbers of atoms of each element are needed to form the compound. The gram atomic mass of sulfur is 32.06, and the gram atomic mass of chlorine is 35.453. 200.2 grams of sulfur corresponds to 200.2/32.06 or about 6.2445 gram atoms of sulfur, while 100.3 grams of chlorine corresponds to 100.3/35.453 or about 2.83 gram atoms of chlorine. Therefore, chlorine is the limiting reactant among these amounts of sulfur and chlorine.
reactant
This depends on the reaction involved.
Reactant
Oxygen is a reactant
product
Reactant- glucose and product- carbon dioxide.
Sugar can be both a reactant and a product, depending on the chemical reaction. For example, in the process of photosynthesis, sugar (glucose) is produced as a product. However, in the process of fermentation, sugar is a reactant that is broken down to produce other products like ethanol and carbon dioxide.
Glucose is a product of photosynthesis and a reactant in cellular respiration.
For copper, it is an element. It could be both reactant and product. While purifying copper will be the product. But copper would be the reactant in case of preparing hydrogen or copper sulphate salts.
Chlorine can be both a reactant and a product, depending on the chemical reaction it is involved in. It can react with other substances to form new compounds as a reactant, or it can be generated as a product from certain reactions.