In addition to formaldehyde, acetaldehyde, ethylene, propylene, etc., methanol, ethanol, etc., metha

There are so many that there are thousands of organic matter, how can they all be told to you, just remember the definition of homologues to be able to tell the difference.

Methane and propane are homologues. Methane (the system name is "carbon alkane", but it only appears when introducing the nomenclature of the system, and the customary name "methane" is generally used) is widely distributed in nature, methane is the simplest organic matter, is the main component of natural gas, biogas, pit gas, etc., commonly known as gas.

Propane, chemical formula ch ch ch, colorless, liquefiable gas. Slightly soluble in water, soluble in ethanol and ether. After mixing with air, it forms a ** mixture.

Present in natural gas and petroleum pyrolysis gas. The chemical properties are stable and not easy to undergo chemical reactions. It is used as a refrigerant, fuel for internal combustion engines or raw materials for organic synthesis.

Answer: B is correct.

A: Ethylene can fade the potassium permanganate solution, but methane cannot, but the premise is that the potassium permanganate solution contains H+. The title does not tell that it is acidic, so the two cannot be distinguished by potassium permanganate solution.

B: It is ethylene that can discolor bromine water, and methane that cannot fade bromine water, because ethylene and bromine water have an addition reaction. This addition reaction can be used to remove ethylene by passing the gas mixture through excess bromine water without introducing new substances.

C: Hydrogen and methane do not react. Hydrogen can react with ethylene under catalytic conditions, but there is no obvious phenomenon and it cannot be identified.

D: The experimental phenomena of ignition and ignition are basically the same, and it is impossible to distinguish them.

Therefore, choose B

A will oxidize these two substances, B ethylene will be added with bromine, so that the solution will fade, and ethylene will be removed C, which can not be identified, and can not remove impurities (will bring in H2) D is also not able to remove impurities.

The molecular formula of ethylene is C2

The molecular formula of H4 methane is CH4

The molecular formula of ethane is C2

The molecular formula of H6 propyne is C3

The H4 molecular composition is not different from each other as many CH2

Therefore, it is not an isomer of ethylene;

The formula of pentene is CV punch C5

The difference in the molecular composition of H10 is 3 CH2

clusters of atoms, similar in structure, homologues to each other;

Therefore, d

Methane, ethane, and ethanol do not contain carbon-carbon double bonds and are not homologues of ethylene; Propylene belongs to the homolog of ethylene, so c is correct;

Test Points: Aromatic Hydrocarbons, Hydrocarbon Groups and Homologs Special Topic: Homologs and Isomers Analysis:

Substances with similar structures and differing by one or more CH2 clusters in molecular composition are called homologues. Substances that are homologues meet the following special points: similar structure, similar chemical properties, the same general formula of the molecular formula, and different molecular formulas; The ethylene molecule contains 1 carbon-carbon double bond, and the other chemical bonds are all single bonds, so each option is judged according to a methane molecule is all single bonds, there is no carbon-carbon double bond, and the structure is not similar to ethylene, so methane and ethylene must not belong to homologues, so a is wrong; b ethane is an alkane, there is no carbon-carbon double bond in the molecule, and the structure is not similar to ethylene, so ethane and ethylene must not belong to the homologue, so b is wrong; c The propylene molecule contains a blind high-carbon carbon double bond, which is similar in structure to ethylene, and there is a CH2 atomic cluster between propylene and ethylene molecules, so propylene and ethylene are homologues of each other, so c is correct; d The pentene molecule contains 1 carbon-carbon double bond, which is similar in structure to ethylene, and there are 3CH2 atomic clusters between pentene and ethylene molecules, so pentene and ethylene are homologues of each other, so d is correct; Therefore, choose CD Comments: This question examines the judgment method of the homologue, the question is not difficult, the test question focuses on the examination of basic knowledge, pays attention to the concept and judgment method of the grinding ruler of the homologue, and the test question is cheap to cultivate students' ability to flexibly apply the knowledge they have learned

Answer] ethylene or acetic acid; Methane; Benzene; Ethane or ethanol.

Answer analysis] test question analysis: the amount of water and carbon dioxide produced in the reaction is equal, so the ratio of the number of hydrocarbons in the organic matter is 1 2, so it is ethylene or acetic acid; If the amount of water is twice as large as CO2, then that organic matter is methane; If the amount of carbon dioxide is twice that of water, then the ratio of the number of hydrocarbons in the organic matter is 1 1, and therefore benzene; If 3a 2b, then the lead is 1 3 of the hydrocarbons in the organic matter, so it is ethane or ethanol.

Test Points: Examine the calculations related to the combustion of organic matter.

Comments: This question is an examination of basic test questions, and the amount of calculation is not large, mainly focusing on the examination of students' abilities. The solution of this problem is based on the atom conservatism of the cong grinding, and the problem can also be discussed with the help of the combustion formula of organic matter, and it can also be discussed according to Huai Zheng Cover.

Methane and ethylene: both are hydrocarbons, but the simplest formula is different, indicating that the hydrogen content is different, and it does not meet the topic, so it is wrong;

Ethylene and ethanol: The simplest formula of ethanol and ethylene is not the same, and the h content in the molecule is not equal, which does not meet the topic, so it is wrong;

Benzene and acetylene: the simplest formula of both is CH, and the H content in the molecule is equal, which is in line with the topic, so it is correct;

Toluene and o-xylene: the molecular formula of toluene is C7H8, and the molecular formula of o-xylene is C8H10, the simplest formula of the two is different, so the hydrogen content is different, which does not meet the topic, so it is wrong;

Propylene and 2-butene: both are monoolefins, the simplest formula is CH2, the hydrogen content is the same, the symbol is titled, so it is correct;

Therefore, C