Noble gases glow when they are excited because they emit light as they return to their ground state from an excited state. When energy is applied to the noble gas atoms, their electrons become excited and move to higher energy levels. As the electrons return to their original energy levels, they release the excess energy in the form of light, causing the noble gases to glow. This phenomenon is commonly observed in neon lights and other types of gas discharge lamps. **

Yes, these gases can be dangerous if they are inhaled in high concentrations. Carbon monoxide is a toxic gas that can cause symptoms like dizziness, headache, and even death in severe cases. Methane is highly flammable and can pose a risk of explosion if it accumulates in an enclosed space. Therefore, it is important to take precautions and ensure proper ventilation when dealing with these gases. **

Carcinogenic gases are gases that have the potential to cause cancer in humans. These gases can be emitted from various sources such as industrial processes, vehicle exhaust, and tobacco smoke. When inhaled, carcinogenic gases can damage the DNA in cells, leading to the development of cancer over time. Some examples of carcinogenic gases include benzene, formaldehyde, and radon. **

No, not all gases are molecular substances. Gases can be composed of either molecules or individual atoms. For example, noble gases like helium, neon, and argon exist as individual atoms in their gaseous state, while gases like oxygen, nitrogen, and carbon dioxide exist as molecules composed of two or more atoms bonded together. **

Gases conduct electricity when they are ionized or have free-moving charged particles, such as ions or electrons. This can occur at high temperatures, in the presence of strong electric fields, or when exposed to certain types of radiation. In these conditions, the gas molecules break down into charged particles that can carry an electric current. **

Noble gases are inert because they have a full outer electron shell, making them very stable and unreactive. This full outer shell gives them little to no tendency to gain, lose, or share electrons with other elements, which are the typical behaviors that lead to chemical reactions. As a result, noble gases do not readily form compounds with other elements, making them inert. **

Some deadly gases include carbon monoxide, hydrogen cyanide, and chlorine gas. Carbon monoxide is a colorless, odorless gas that can be produced by incomplete combustion of carbon-based fuels. Hydrogen cyanide is a highly toxic gas that interferes with the body's ability to use oxygen. Chlorine gas is a greenish-yellow gas that can cause severe respiratory issues and even death at high concentrations. **

Proofs of gases refer to evidence or demonstrations that show the existence or properties of gases. This can include physical observations such as the expansion of a gas to fill its container, the ability of gases to exert pressure, or the changes in volume and pressure with temperature. Additionally, chemical reactions involving gases can also serve as proofs, such as the combustion of a gas or its reaction with other substances. Overall, proofs of gases are the empirical evidence and experimental results that support our understanding of the behavior and characteristics of gases. **