Discuss what it takes to do chemistry problems, especially metals and solutions

Metal questions: First of all, according to the prompts of the question stem, make a general assumption, and try to guess the metals that have been learned and have a high probability of occurring, such as iron, copper, aluminum, etc. To have this intuition, it often depends on your mastery of metal knowledge, and the unique properties of various metals to keep in mind, such as aluminum can react with both acids and bases, and the precipitation of iron is reddish-brown.

The inference problem of metal is often either unable to deduce one, or one is introduced, and everything else is easily solved. So memorize the basics, make bold conjectures, and you can get a high score in the inference question.

The calculation method of metals is roughly to list equations, and then calculate proportionally, the key is to remember the equations, pay attention to the balance, be careful in the calculation, and the problem is not big.

Most of the multiple-choice questions on metals are also about the nature of metals, and you have to systematically sort out and understand them.

Solution: It is not difficult to calculate if you are familiar with several formulas, such as the conversion formula between c1v1= and w.

If you choose, the solution is basically not the focus of the investigation, and if you focus on it, you should pay attention to the differences between the solution, colloid, and turbidity, and their unique properties, such as colloids have Tyndall effect.

To learn chemistry, we need to go deeper and deeper from the people around us, such as the organic matter around us, the plastics, metal materials, and tools we use. Drinking aqueous solution, their constituent elements are basically the same, and the difference in properties is great, it means isomerism, and so on and metals, their difference lies in their nucleus, and metals basically have their common properties, such as reaction with acid, etc., their difference is related to atomic number, electron layer, etc. The solution is divided into solute solvents, and they basically follow a similar missolution pressure, but if they say that there are other atoms or clusters, then their properties are affected by the other atoms or clusters.

Chemistry is not complicated, and there are their merits and faults around them outside, and it is not so mysterious.

Read the chemical equations in the textbook and the explanations below. Not once, twice.

My word is too bad, so please look at the picture, click to see the big picture because it is a new type of water purifier, so I thought of aluminum hydroxide colloid, the answer is not necessarily correct, but there should be merit, I hope you will not hesitate to teach.

From your answer, I know that impurities are not considered, but I think that B cannot be silicic acid and aluminum chloride since it is solid, and D is obtained from C, so C is aluminum chloride and D cannot be silicic acid. So I think there might be something wrong with your answer.

I think B is a small amount of impurities and hydrolysis to obtain a small amount of silicic acid and aluminum hydroxide C is a sodium salt solution, and there are silicic acid heels and metaaluminate.

d is silicic acid and aluminum chloride.

F is silicic acid precipitation and E is aluminum chloride solution.

I'm just a sophomore. I don't understand, I don't understand I haven't studied chemistry yet.

Keep in mind the atomic mass of each element, and make sure you don't miss out how many of each element there are, or simply write them down on paper. You can also list a **, the first row of element names, the number of atoms in the second row, and the mass number in the third row, which is very intuitive. If you do this, you will become familiar with it, and you will be able to have ** in your heart in the future.

3: (14*2)/(14*2+4+16*3)*100%=35%

4: I don't have time to do it.

5: Not to mention.

The answer is so-so... Rattle.

The relative atomic mass of an element multiplied by the number of atoms.

The general formula of saturated monobasic aldehyde is CNH2NO

Mix the solution with freshly prepared Cu(OH)2 to generate a red precipitate as Cu2OnCu2O=

mol because of the aldehyde group.

And. cu2o

The quantity ratio of the substance is.

So. n aldehyde group =

m mixture = 100

117g of 4 grams of aldehyde content taken out.

then the average relative atomic mass of mixed monoaldehyde =

Then the relative atomic mass of ab is less than and greater than, respectively.

Acetaldehyde relative atomic mass = 44 is known

Propionaldehyde relative atomic mass = 58

Because b is one more carbon atom than a.

So b is propionaldehyde.

a is acetaldehyde.

NO2 Let the chemical formula of the substance be NXOY.

14x+16y=46

14x/16y=7/16

Solve x=1, y=2, so it's no2.

Let the chemical formula be nxoy

14x：16y=7：16

14x+16y=46

The solution is x=1 y=2

The chemical formula NO2 is nitrogen dioxide.

It should be a very common nitrogen dioxide, right? Look at the molecular weight.

Let the chemical formula be nxoy, and the above two equations can be combined by the problem, 14x+16y=46, (14x) (16y)=7 16.

Carbon dioxide contains carbon.

Water contains hydrogen. 1) The minimum mass of combustibles is:

The mass ratio of carbon dioxide to water produced is :9

16g is completely burned in oxygen, 24g of oxygen is consumed, and carbon dioxide is generated (16g+24g)*11 20=22g water 18g

Combustibles 16g carbon 22g*12 44=6g hydrogen 18g*2 18=2g oxygen 16g-6g-2g=8g

The mass ratio of carbon, hydrogen, and oxygen elements is 6g:2g:8g=3:1:4

The title is incorrect: the water produced should be, or carbon dioxide should be 44g: the conservation of carbon dioxide should be written according to c and h, and the ratio of c and h in combustibles should be written, c:h=1:4

1) The molar mass of combustibles is the smallest and meets the requirements of 1: CH4 + 2O2 = = = CO2 + 2H2O, (2) because there is C: H = 1:

4, i.e., CO2:H2O=1:2, can be generated by the conservation of mass, 1mol of water, known oxygen reacts to the conservation of the elements

The ratio of the quantities of each elemental substance is c:h:o=2:

8:5, the mass ratio is 3:1:

10。Looking at it again, it seems that there is no substance that matches the calculation!!