Chemistry Elective 5 Answer 15, Sophomore Chemistry Elective

If there is a problem with the stem, it should be that the ratio of the number of hydrogen atoms to carbon atoms on the hydrocarbon group is 2:1, which means that there is no -ch3 and -ch structure, then the organic substance has no carbon-carbon double bond and carboxyl group (-co), and it is known that the organic substance has a hydroxyl group, then the simple formula of the structure is assumed.

ho-(ch2)n-oh

When n=1, the molecular mass is 50, which is not discarded.

When n=2, the molecular mass is 62, which is in line with the title.

Then this organic matter is propylene glycol.

ho-ch2-ch2-oh

ch2oh-ch2oh

The ratio of the number of hydrogen atoms on the hydrocarbon group to the hydroxyl group is 2:1, assuming that both the hydroxyl group and the hydrogen are attached to the same carbon atom, then each carbon atom is connected to one hydroxyl group and two hydrogens. According to the relative molecular mass of 62, it can be seen that there are two such carbon atoms.

Ethylene glycol, I can write the structural formula, I don't know how to type the structural formula on the computer.

The four reaction equations are denoted by , respectively. Rule.

So the energy expression is 2 e4=e1-1 3(e2+2 e3)=e4=

Usually no one will give you an answer to this question, go to Xinhua Bookstore or something to buy a teacher's book, it's really not good, and the queen seems to have the answer.

Damn, I can't go into details, the publishing house, the editor-in-chief or something.

Excess NAOH, calculated as hydrochloric acid, generates 50* heat released from water, with a total mass of 100 g after the reaction.

Q = -3 to the power (unit changed to kj).

The neutralization reaction is exothermic when 1mol of water is generated.

q'= -3 power for reference.

The answer is a. Because the heat of neutralization of the reaction between a strong acid and a strong base is almost the same as the heat of neutralization, which is the heat released when 1mol of water is generated. That's why I think A

Alkane C2H6, alkyne liquid hydrocarbon C2H2, olefin C4H8, three mixed together, the general formula is the same as alkene:

The number of carbon atoms in the general formula is: buried bypass(2*1+2*1+4*2) 4=3, and the general formula of mixed hydrocarbons is C3H6

The reaction formula is: 2C3H6 + 9O2 = 6CO2 + 6H2OCO2 + H20 total, the amount of its substance can be calculated as N (CO2) = and then the amount of C3H6 substance is obtained, the amount of O2 substance is, the mixture of oxygen and hydrocarbons is 840ml, and the amount of its total substance can be found as.

Residual gas n=

Talking about Tongji:

Alkanes C2H6, alkynes C2H2, olefins C4H8, three mixed rocks together, the general formula is the same as alkenes:

The number of carbon atoms in the general formula is: (2*1+2*1+4*2) 4=3, and the general formula of mixed hydrocarbons is C3H6

Reaction formula: defeat 2C3H6 + 9O2 = 6Co2 + 6H2OCo2 + H20 total, the amount of its substance can be calculated as N (CO2) = and then the amount of C3H6 substance is obtained, the amount of O2 substance is, the amount of oxygen and hydrocarbon mixture is 840ml, and the amount of its total substance can be found as.

Residual gas n=

Volume: Well, that's about it, I won't ask again.

Damn, the answer is exactly the same, isn't this legendary cheating?

Concentrated H2SO4 weight gain, this is water, the amount of matter is, then the H element has soda lime weight gain, this is CO2, the amount of the substance is, then the C element has here, the ratio of the number of C elements and H elements is the ratio of the amount of the substance is 6:16=3:8, so only C C3H8O meets the situation

Only it is 3:8.

C, concentrated H2SO4 absorbs water, calculates that water has, alkali lime absorbs CO2, calculates CO20, calculates the oxygen according to the conservation of hydrogen and carbon, and then calculates the ratio of carbon, hydrogen and oxygen according to the proportion.

x=naoh

y=hno3 (rare).

z=agno3

Y: Neutralizes excess alkali and prevents the appearance of silver oxide.

Contains Cl relative molecular weight VP*108 170

Test the complete precipitation: take an appropriate amount of the remaining solution, dilute nitric acid acidification first, and then add AGNO3