Q1: Berl saddle made of carbon cannot be used for

ANS:D - oxidising atmosphere

An oxidizing atmosphere, also known as an oxidizing environment or oxidizing atmosphere, refers to a gaseous environment containing a higher concentration of oxygen or other oxidizing agents compared to a neutral or reducing atmosphere. In an oxidizing atmosphere, there is a tendency for substances to undergo oxidation reactions, where they lose electrons or increase their oxidation state. Here are some key points about oxidizing atmospheres:

1. Presence of Oxygen: The primary characteristic of an oxidizing atmosphere is the presence of oxygen gas (𝑂2O2​) or other oxidizing agents such as ozone (𝑂3O3​), hydrogen peroxide (𝐻2𝑂2H2​O2​), or chlorine (𝐶𝑙2Cl2​). These agents are capable of accepting electrons from other substances, leading to oxidation reactions.
2. Oxidation Reactions: In an oxidizing atmosphere, oxidation reactions are favored, where substances lose electrons. This can lead to changes in the oxidation state of elements and the formation of oxides or other oxidized products. For example, metals can corrode or rust when exposed to oxygen in the atmosphere.
3. Effects on Materials: Many materials are susceptible to degradation or damage in oxidizing atmospheres. For example, metals may corrode, organic materials may undergo combustion, and carbon materials may oxidize. Certain polymers and plastics may also degrade when exposed to oxygen over time.
4. Applications: Oxidizing atmospheres are commonly encountered in various industrial processes and applications, including combustion processes (e.g., combustion engines, furnaces), chemical manufacturing (e.g., production of oxidizing agents, oxidation reactions), and environmental processes (e.g., atmospheric oxidation, wastewater treatment).
5. Safety Considerations: In some cases, the presence of an oxidizing atmosphere can pose safety risks, especially in situations where flammable materials are present. Proper ventilation and safety precautions are often necessary to minimize the risk of fires or explosions.

Overall, an oxidizing atmosphere is characterized by the presence of oxygen or other oxidizing agents and favors oxidation reactions, which can lead to material degradation and changes in chemical composition. Understanding and controlling oxidizing atmospheres are important in various industrial, environmental, and safety contexts.