Ethylene is a ______ phase fuel.

Ethylene is a ______ phase fuel.

• A. Gas
• B. Liquid
• C. Solid
• D. Plasma

Answer: (A)

Ethylene is a gas at ordinary temperatures and pressures. Its boiling point is about -103.7°C, so above that temperature it exists as a vapor/gaseous fuel. This gas form is why it mixes with air to create flammable vapors and is the typical state considered when discussing its fire hazards. The other states would only occur under extreme conditions not encountered in everyday use: a liquid would require cooling far below room temperature, a solid would require even more, and plasma is an ionized state that happens only under very high energy. So the phase that aligns with how ethylene is encountered as a fuel in practice is gas.

Ethylene is a gas at ordinary temperatures and pressures. Its boiling point is about -103.7°C, so above that temperature it exists as a vapor/gaseous fuel. This gas form is why it mixes with air to create flammable vapors and is the typical state considered when discussing its fire hazards. The other states would only occur under extreme conditions not encountered in everyday use: a liquid would require cooling far below room temperature, a solid would require even more, and plasma is an ionized state that happens only under very high energy. So the phase that aligns with how ethylene is encountered as a fuel in practice is gas.