Q1: Which of the following is not a commercially used feed-stock for the production of ammonia synthesis gas?

ANS:C - Tar

Tar is a dark, thick, sticky substance that is produced through the destructive distillation of organic materials such as wood, coal, petroleum, or peat. It is composed of a complex mixture of organic compounds, including hydrocarbons, phenols, and various other organic chemicals. The production of tar typically involves heating organic materials in the absence of air, which causes them to decompose and release volatile compounds. These volatile compounds are then condensed into a thick, viscous liquid known as tar. Historically, tar has been used for various purposes due to its waterproofing and adhesive properties. For example, it has been used in the construction industry to waterproof roofs, in shipbuilding to seal the hulls of ships, and in road construction to bind aggregates together in asphalt. However, the use of tar has declined in many applications due to environmental and health concerns associated with its toxic components, such as polycyclic aromatic hydrocarbons (PAHs), which are carcinogenic. As a result, alternative materials and processes have been developed to replace tar in many applications, particularly in areas where human exposure or environmental contamination is a concern.