Engineering University Chemistry Test Solution, College Chemistry Problem Solution! Thank you

1 Chapter 17 Organic Chemistry and Reactions.

There are 55 exercises (155 small questions) at the end of this chapter, of which 20 are big questions (38 small questions).

11 Exercise 16 Use the reaction formula to denote the main products of the following reactions:

1) Intramolecular dehydration of 3-methyl-3-pentanol.

2) 3-bromo-2,5-dimethylhexane interacts with potassium hydroxide in alcohol.

3) 4-methyl-1,4-pentanediol eliminates a molecule of water.

13 Exercise 20 Arrange the following compounds in the required order:

15 Exercise 24 Synthesis of compounds from specified raw materials (inorganic reagents optional).

16 Exercise 26 Synthesis of the following compounds with ethyl acetoacetate using methanol and ethanol as raw materials (inorganic reagents optional).

1) 2-pentanone (2) 3-methyl-2-pentanone.

17 Exercise 28

Compound A has the molecular formula C6H10O, which can interact with PCL3 and can also be oxidized by KMno4. A can absorb br2 in CCL4 without releasing HBR; A is catalytically hydrogenated to obtain B, and B oxidation can obtain C, and the formula C is C6H10O; B reacts with H2SO4 at high temperature, and the obtained product is reduced to form D, the molecular formula D is C6H12, and the boiling point is 80. Try to write out the possible constructs for a.

18 Exercise 31

The molecular formulas of compounds A, B and C are all C3H6O2, A reacts with sodium carbonate to release CO2, B and C cannot, but when heated in sodium hydroxide solution, it can be hydrolyzed. The liquid distilled from the hydrolysate of B can undergo an iodoform reaction, and the structure of A, B, and C is speculated.

19 Exercise 38

There are three possible ways to synthesize p-chloro-thyrobenzoic acid from p-chlorotoluene, which of them is the best? Why?

1) nitrification first, then reduction, and then oxidation;

2) nitrification first, then oxidation, and then reduction;

3) First oxidation, then nitrification, and then reduction.

20 Exercise 39

The molecular formulas of A, B, and C are all C4H11N, and when they react with nitrous acid, A and B form an alcohol containing four carbon atoms, while C combines with nitrite to form a salt. The alcohol obtained from A is oxidized to isobutyric acid, and the alcohol obtained from B is oxidized to form butyric acid. The structural formulas of a, b, and c were introduced on a trial basis.

21 Exercise 41 Complete the following responses:

22 Exercise 53

The molecular formula of a compound is C3H7O2N, which has optical rotation, can react with NaOH and HCl, can react with alcohol to form esters, and reacts with nitrous acid to release nitrogen.

This is a typical class of non-canonical carbocations with bond involvement.

When Tso- is in the trans position, the electrons on the double bond on the other side have a tendency to bridge the carbon from the back side to the carbon and form a stable carbocation, and the pro-group promotion action forms a non-classical carbocation, making it easier for TSO- to leave, and ACOH attacks the carbocation from the same side, and the configuration is maintained.

In the cis position, the electrons cannot stabilize the carbocation from the back side, and the Tso- departure ability is weaker than in the above case, while most of the electrons are attacked from the back by ACOH, and the Tso- leaves, and the configuration is reversed and the rate is slower.

Ideas for reference.

The relationship between the equilibrium constant of the redox reaction and the standard battery electromotive force is mainly investigated, and the direction of the reaction is judged by the electromotive force of the battery.

The first question is to find the equilibrium constant.

The equilibrium constant has nothing to do with concentration, so don't be misled. It is only necessary to use the formula for the relationship between the equilibrium constant and the standard electromotive force. Specific:

1. Write out the chemistry of the trim.

2. According to the gain and loss of electrons in the reaction, judge the positive electrode and the negative electrode.

3. Subtract the negative standard electrode potential from the positive standard electrode potential to obtain the standard electromotive force of the galvanic battery.

4. According to the formula of the relationship between the standard electromotive force and the equilibrium constant of the galvanic battery, the equilibrium constant is obtained.

The second question, judging the direction of reaction, judging by the electromotive force of the battery at this moment, greater than 0 is positive, less than 0 is reverse. Specific:

1. According to the previous reaction equation and the standard electromotive force of the galvanic cell, according to the Nernst equation of the galvanic cell, the electromotive force of the galvanic cell at the moment is obtained.

2. Compare the size with 0 to determine the direction of reaction.

1.Specific:

2*(400 112) (400 ionized by electrolyte becomes twice as much.2The osmotic pressure inside the membrane is much greater than that outside the membrane, squeezing out the solute NaCl. The mass concentration of the substance is the same, depending on the size of the molar mass, the larger the concentration, the greater the osmotic pressure.

a，pbcl2

b，agcl

c，ag(nh3)2 +

d，agie，pbs

f，pb(no3)2

g，sh，no

i，pb(oh)2

j，pb(oh)3 -

k，pbo2

L, PbCl2 (or H2O)L and A are the same substance? It is H2O more likely to be M, Cl2

There are a lot of obvious hints for this question, mainly including:

The precipitate generated with AG ions can be dissolved by ammonia, and it is obvious that it is precipitated as AGCL, and then it is obviously AGI formed with silver ammonia complex ions and Ki, so there are CL ions in A.

and hydrogen sulfide to form a black precipitate, and the black precipitate is dissolved in concentrated nitric acid to form a colorless solution, color precipitate and colorless gas, indicating that the cation in a is pb, and the later inference is simple.

See upstairs for the full answer.

1. First, find the boiling point elevation constant kb, and the known mass molar concentration: m = [ m(c6h6)] 1000 40 = ( 78 ) 40 = (mol kg-1 solvent).

t = kb *m

kb *kb =

2. Find the molar mass m of the unknown

/ m ) / 40

m = 69

The volume of H2 was converted to the volume under standard conditions, and the amount of Na was calculated from H2 2Na.

The total amount of NaOH is calculated according to HCL, and the NAOH generated by the NaH reaction is the amount of NaOH generated by the NaH reaction.

The total amount of sodium is calculated based on the amount of hydrochloric acid, and then the two equations are solved.