Physical property
Under normal circumstances, ethylene is a colorless slightly odorous gas with a density of 1.256q, slightly less dense than air, difficult to dissolve in water, easily soluble in organic solvents such as carbon tetrachloride.
Appearance and properties: colorless gas, slightly with a unique smell of hydrocarbons. A small amount of ethylene has a faint sweetness.
Absorption peak: The absorption band is in the far ultraviolet region.
Solubility: insoluble in water, slightly soluble in ethanol, ketone, benzene, ether. Soluble in organic solvents such as carbon tetrachloride.
Ethylene source

The main source of ethylene production is petroleum.
Ethylene is an important chemical raw material, and its output is a symbol of the level of petrochemical industry in a country. The production of ethylene is mainly dependent on the processing of petroleum, including direct distillation of crude oil, secondary processing of distillates, and natural gas and oil field gas. These raw materials through chemical processing, can produce ethylene, and then used in synthetic fibers, synthetic rubber, synthetic plastics and other chemical products. Ethylene industry is the core of petrochemical industry
Ethylene products account for more than 75% of petrochemical products and occupy a very important position in the economy. Therefore, oil is the main source of ethylene production, and its level of production and consumption is often regarded as an important indicator of a country's economic development and industrialization

Main use
1. Industrial field
Uses: Manufacturing plastics, synthetic ethanol, acetaldehyde, synthetic fiber and other important raw materials.
2. Ecological field
The triple response of ethylene:
① Inhibit stem elongation and growth; :
② Promote the thickening of stems and roots
③ Promote the lateral growth of stems. Treating the stems of yellowed seedlings with ethylene can make the stems thicken and the petioles grow upward.
3. Agriculture
Ethylene is a plant endogenous hormone, all parts of higher plants, such as leaves, stems, roots, flowers, fruits, tubers, seeds and seedlings will produce ethylene under certain conditions. Its physiological function is mainly to promote the expansion of fruit and cells. It also has the functions of inducing flower bud differentiation, breaking dormancy, promoting germination, inhibiting flowering, organ shedding, dwarfing plants and promoting adventitious root formation.