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Of course, choose C, C is not right, cardiovascular patients can eat animal fat, supplement animal protein, I haven't heard of cardiovascular disease can not eat meat To give you an example, cardiovascular patients should eat more fish or cod liver oil, just to soften blood vessels, so animal fat is good for cardiovascular patients, absolutely not to eat is wrong.

Even if you don't know these and don't know the usefulness of animal fat, you can judge correctly, because C is too absolute, in general"Definitely","Absolutely"It's all wrong.

A is right, you will know the biology of the introduction of fats, sugars, inorganic salts and so on in biology is very clear.

B Yes, for example, Luhua peanut oil is vegetable oil, liquid, roast mutton, the mutton fat should be roasted on the fire is liquid, and when it is not roasted, it is solid.

For example, if you don't eat for a few days, you will lose weight.

You can choose the right question from the words on the question, and the general chemistry questions will not be so biased, and if the general deviation is biased, you can pass"Definitely","Absolutely"Something is wrong.

Gases that are insoluble in water are collected, and gases are basically fed through short ducts, while water is exported from long ducts. The answer is c, d.

Summary. Some half-cells do not have conductive electrodes, and all the substances in the half-reaction are in the electrolyte solution, and these half-reactions are designed to be used as companion cells with electrodes. The electrode material should not change the thermodynamic properties of the chemical reaction of the half-cell and should be thermodynamically inert, so graphite can generally be used as the semi-reactive battery.

How, please.

**It's not very clear about kissing, can you send it again? Good work.

See. Will it.

Write your <> first

Is that all.

The first and second batteries.

And two and three.

Thank you. Analysis and Q&A] The writing of battery symbols is divided into the following three processes: 1. Find out the positive and negative electrodes, the negative electrode with increased valency, the positive electrode with decreased tremor 2, the negative electrode is written on the left side, and the positive electrode is written on the right side 3<>

Some half-cells do not have conductive electrodes, and all the substances in the semi-reactive amplifier are in the electrolyte solution, and these semi-reactive companion cells need to be equipped with electrodes. The electrode material chosen should not alter the thermodynamic properties of the half-cell chemistry and should be thermodynamically inert, so it is prudent to use graphite as the semi-reactive battery. <>

Nitric oxide and oxygen react to form nitrogen dioxide, and after the nitric oxide is completely reacted, nitrogen dioxide and nitrogen tetroxide are reversibly converted. The specific reaction formula is 2NO+O2=2NO2

So the volume increases.

2no2=n2o4

Volume reduction.

At the beginning, NO and O2 react to form NO2, so the gas decreases, and when all NO becomes NO2, it is equivalent to just passing O2, so it will increase.

First of all, 2NO+O2=2NO2

Watch out for a special reaction, though.

2NO2==N2O4 (reversible) so the volume decreases.

As the reaction progresses, the NO is consumed and the O2 continues to increase, so the volume increases again.

At the beginning, the reaction is 2NO+O2=2NO2, and two molecules of gas are produced from three molecules of gas, so the gas volume is reduced.

After the reaction is complete, this reaction does not occur, so the volume is the volume of NO2 plus the volume of O2 that is introduced, so the volume is increasing

The first two students are right, because the generated NO2 will decrease because of the bimerization volume, but the generated NO2 volume will not change.

Reactions occur at the beginning 2NO+O2=2NO2 and 2NO2=N2O4

When this reaction occurs, the volume of the gas gradually changes from 2 volumes to 1 volume. Therefore, the volume of the gas decreases.

Later, with the increase of N2O4 concentration, the reverse reaction speed gradually increased, and the N204=2N02 reaction intensified. Coupled with the introduction of O2, the volume of the gas increases relatively.

NO2 and O2 react to form NO2, NO2 and H2O react to form HNO3, so the gas volume decreases quickly, and then NO2 is gone, only O2 is introduced, so the volume increases.

It is a matter of chemical reaction equilibrium.

2NO+O2 = (is an invertible symbol) 2NO2

In a constant volume vessel, the increase in O2 means that its concentration increases, and according to the principle of Le Chatelier, the reaction moves in the direction of the positive reaction, so the total volume becomes smaller. After the equilibrium is reached, the oxygen continues to flow in, the equilibrium does not move, and the total volume becomes larger.

Actually, the explanation can be explained in this way, but if there is no2, there must be n204, 2no2 = (invertible symbol) n2o4

This is also a problem.

Essentially, this is a complex reversible reaction.

NO and O2 react to form NO2, so that 2 units of NO and 1 unit of O2 react to generate 2 volumes of NO2, so when NO is not finished reacting, 3 unit volumes become 2 units, and the total volume decreases by 1 unit, and when NO is finished reacting, the oxygen introduced will increase as much as it is.

Therefore, after the reaction, the volume of the gas decreases first and then increases.

As can be seen from the question, x:z=15:(15+10)=3:5

Therefore, according to the law of conservation of mass, x:y:z=(15*3 5):(30-15-15*3 5):15=3:2:5

Adding 10 grams of Z, X and Z are just completely reacting, indicating that the mass ratio of X and Z reaction is 15g: (15 10) g, then when 30 grams of new substance M are generated, the masses of the three substances are 9g, 6g, and 15g respectively, then the mass ratio of xyz in the reaction is 3:2:5

The alcohololysis reaction of acid chloride is the oxygen nucleophile of the alcohol hydroxyl group attacking the carbonyl carbon of the acid chloride, so the stronger the electron-withdrawing effect of the substituents of the acid chloride, the stronger the reactivity.

Among the four substances, the para-substituents of benzoyl chloride are as follows:

Chlorine: weak electron-withdrawing effect.

Nitro: strong electron-withdrawing action.

Methoxy: Electron pushing.

Therefore, the order of reactivity is: p-nitrobenzoyl chloride " p-chlorobenzoyl chloride " benzoyl chloride " p-methoxybenzoyl chloride.

First of all, this reaction is a nucleophilic substitution reaction mechanism, so the stronger the positive charge on the carbonyl carbon, the higher the reactivity.

The nitro group is a strong electron-withdrawing group, the chlorine group is the electron-absorbing group, and the methoxy group is the electron-donor group, so the reactivity decreases in turn.

Results: p-nitrobenzoyl chloride p-chlorobenzoyl chloride p-chloroyl chloride p-methoxybenzoyl chloride.

Looking at the electropositivity of acyl carbon, the more positive the reactivity, the higher the activity.

cxhy+(x+y/4)o2→xco2+(y/2)h2o

The volume before and after is unchanged, that is, the stoichiometric numbers on the left and right sides of the above equation are equal (water is a gas at 120 degrees), that is, 1+x+y 4=x+y 2, which is simplified to y=4