Sophomore Organic Chemistry Questions! Desperate for answers

Because it is fully combusted, there may be a surplus of oxygen. Assuming that the gaseous hydrocarbon has n carbons, then there is at least n * 10 (ml) gas, so the last two are excluded. (The amount of oxygen in the last two is also insufficient).

A: 2C2H6 + 7O2 = 4CO2 + 6H20, 10ml of hydrocarbon consumes 35ml of oxygen, 20ml of CO2 is generated, and finally 35ml is left, possibly.

B: 2C3H6 + 9O2 = 6CO2 + 6H20, 10ml of hydrocarbon consumes 45ml of oxygen, 30ml of CO2 is generated, and 35ml is left, possibly.

Solution 2: Let the molecular formula of hydrocarbon be CXHY, because for C, a carbon atom consumes 1 molecule of oxygen and generates 1 molecule CO2, so the number of carbon atoms does not affect the amount of gas before and after the reaction, but the volume of the original hydrocarbon disappears.

For H, each H atom consumes molecular oxygen, so each hydrogen in the hydrocarbon reduces the gas content by a multiple of the hydrocarbon volume.

Before and after the system reaction, the volume of the original hydrocarbon disappeared, and it was also reduced by 15ml, which is a multiple of the volume of hydrocarbon, so y=

In addition, since the amount of oxygen should be sufficient, C is not good, and AB is chosen

The correct one above B is A is not a hydrocarbon and B is a naphthenic hydrocarbon, so A should be eliminated and B should be selected

It is easy to know that the water generated in this question is in a liquid state, and this kind of problem uses the gas volume difference method, the first three options are to reduce the total amount of gas by 2.5 moles for each mole of reaction, that is, for each volume reaction, the total gas volume is reduced by 2.5 volumes, and the fourth option is 3.5 volumes. According to the problem, the total amount of gas is reduced by 25 milliliters, and it can be seen that for the first three options, the consumption of CXH6 ten milliliters is all to participate in the reaction, so it is only necessary to consider whether the amount of oxygen is sufficient, and the oxygen can remain without participating in the reaction, but if it is not enough, it does not meet the topic, so it is easy to know that option A needs 35 milliliters of oxygen, option B requires 45 milliliters, and option C requires 55 milliliters. It's clear that option C doesn't fit the topic.

For the option, it is easy to reduce the volume by 25 milliliters and only consume 7.0 milliliters of C4H10 so there is a surplus, then only need to consider whether the oxygen given is in line with the 7.0 milliliters of C4H10 to react, obviously the amount of oxygen given does not meet the data, so the answer is AB

The aldehyde is propionaldehyde, C3H6O, and the structure is simplified: CH3CH2CHO

From the inscription, the gram of weight gain is the mass of ag, and the molecular formula of aldehyde can be obtained from the relation r cho 2ag.

Students, it's a question in the chemistry workbook!

I did. That is true.

From the increase in the mass of the flask, the gram can be known as the mass of the formation of silver, and the relative molecular mass of silver is 108, from which it can be obtained that silver has moles. Then saturated monoaldehyde has moles.

Then you can forget it.

It is also possible to use this method:

r－cho ——2ag

r+29 216

10 is obtained by the proportional relationship between the two (r+29)* = 10 * 216r+29 =58 r=29

Because it is a saturated monoaldehyde, the attached R group can be set to —CNH(2N+1)12N+2N+1=29 N=2

So the R group is —ch3ch2

Hence this aldehyde is propionaldehyde.

(1) M= VM at the same temperature and pressure can be deduced from =m v, n=v vm, n=m m, so the relative molecular mass of the substance is 8; The amount of the burning sample substance is that the complete combustion product passes through the concentrated H2SO4, and the mass increased by the concentrated H2SO4 is water [in fact, looking at the second question, it can be seen that the substance contains N elements, but N is completely burned to form N2], and the amount of the substance is , which contains H; What is absorbed through soda lime is CO2, the amount of the substance, which contains c; Also, the same amount of sample produces the amount of N2 substance, which contains n is.

Therefore, from the conservation of atoms, we can know that the molecular formula A is C9H9NOX; and from the relative molecular mass of x is 3

Hence the molecular formula A: C9H9NO3 (or C9H9O3N).

2) Here is a biochemical common sense, that is, glycine: in fact, glycine, or 2-aminoacetic acid, is the simplest amino acid, with the simple structure formula H2NCH2COOH and the molecular formula C2H5NO2; Glycine and B are dehydrated and condensed to form A, and water participates in the process, so H and O have changes, but C atoms can be directly added or subtracted, so the number of C atoms in B is 9-2=7;It is also composed of "B substances, which are composed of only three elements: C, H, and O. The ratio of the quantities of its matter is 7:

6:2 "It can be seen that the molecular formula B is C7H6O2, which is 10 H less than the saturated paraffin C7H16, and the unsaturation is 5, which is very likely to contain a benzene ring (in fact, it is not necessarily, it may also contain double, triple bonds, etc., but in that case, there are too many possibilities, it is too troublesome to list them one by one, and generally in this case, the topics to be examined are all benzene rings), so B is likely to be benzoic acid PH-COOH (PH- stands for benzene ring).

B is dehydrated and condensed with C2H5NO2 to form A, so A is PH-Co-NH-CH2-COOH [PH- stands for benzene ring].

1.118 * So the mass of hydrogen is 10, there are 10 hydrogen atoms, then the number of carbon atoms is 5, the mass of oxygen atoms = 118-10-5x12 = 48, and the oxygen atom has 3 A molecular formula C5H10O3

2. Structure of B:

3. A can be esterified and polycondensed.

Species: CH3CH2CH2CH(OH)COOH

ch3ch2ch(oh)ch2cooh

ch3ch(oh)ch2ch2cooh

ch3ch2ch(cooh)ch2oh

ch3ch(cooh)ch2ch2oh

ch3ch(ch2oh)ch2cooh5

c5h10o3

Reacting with acidic potassium heavy cadmate, I didn't study ...... in high schoolI'm sorry.

The first problem can be solved by setting the molecular formula (ch2) mon, m and n as unknown sequences, and the binary equation can be solved to obtain m=5, n=3, that is, the molecular formula is c5h10o3.

Question 2: The second question is not a high school question, I can't do it, it is a college organic chemistry question

The structure of b is a carbon linked to 2 methyl groups, a carboxyl group, and primary alcohols...

It means that the structure will not be lost on the computer.

1: Isopropanol or 2-propanol.

2.Pick B. Analysis: Cuo and ethanol will form aldehydes and Cu, dilute nitric acid will dissolve Co and Cu, hydrochloric acid will dissolve Cuo, only lime water does not react only Cuo.

1: ch3ch(oh)ch3 how to name it?

2-Propanol. 2: b lime water.