Find answers to these basics of chemistry

fe2o3 hcl cuso4

feso4 fecl3 baso4

cucl2 ba(oh)2 ba(no3)2alcl3 al2(so4)3 agno3fe(oh)3 agcl3 caco3

cacl2 cao ca(oh)2

nacl bacl2 (nh4)2co3

nh4hco3 nh3 kco3

cuo naso4 na2so4

Blue, black, green.

Too much to write.

Give it a few points.

Find a teacher to sort it out, the accuracy is also high, and it will leave a good impression.

Needless to say, it's such a simple question, and there are so many more.

20 grams precipitate 8 grams So the solubility is 40 grams At the beginning, only 4 grams Unsaturated 200 grams of solution is equivalent to 190 grams of saturated mixed with 10 grams of water, and the excess of the original solute is calculated, and 25 grams of water precipitate 10 grams.

1. China's working people's business congress will make bronzes, and the Western Han Dynasty will smelt iron and steel.

2. The brightest alcohol lamp is the inner flame, and the highest temperature is the outer flame.

3. Compared with exhaled air and inhaled air, the amount of oxygen decreases, and the amount of water vapor and carbon dioxide increases.

4. Chemistry is an experiment-based science.

The first one is like a history question, you look it up again.

1.Xia Shang, Warring States.

2.Outside, inside.

3.Oxygen, carbon dioxide and nitrogen.

4 Experiments.

1.I forgot, I haven't played it for years.

2.Choose D3The order is three-two-one-four.

4.Glass rods. Beaker. Iron frame. Alcohol burner. Asbestos nets.

I hope that others will make up the answer to the first question.

1. Absorb the liquid directly from the graduated cylinder with a rubber tip dropper until the volume of the liquid in the graduated cylinder is observed to decrease.

1 3ml2, c iron frame.

4. Evaporation dish, alcohol lamp, glass rod, iron frame (with iron ring).

Suction a tip dropper with a liquid volume of about 1ml

I'll give you the answer.

1.The separation and purification process of transferring compounds from one solvent to another solvent by using the difference in solubility or partition coefficient of two immiscible solvents.

Common extractants are common solvents, such as gasoline and carbon tetrachloride, which are often used as extractants for the extraction of low-polar or non-polar substances from water. The common extracted substances are halogenated chlorine, bromine, and iodine elements, because they are all non-polar, so the solubility is greater in this kind of organic solvent that is also non-polar, and this law is called "similar miscibility", and you can continue to understand it if you are interested.

The color of the test strip changes: red-yellow is acidic, light green is neutral, and blue-purple is alkaline.

Of course, this is all quite rough, and I can't describe all the colors of the pH test strip in words, but the pH test strips have a "standard color chart" for you to compare, so it is not a question of what color represents what pH.

As for the principle, you can roughly understand that there is an organic substance with color reaction on the pH test paper, and what color it shows is related to the concentration of hydrogen ions in the system in which it is located, so the color of the solution with different pH is not the same.

3.The discoloration range of methyl red is red) yellow), which means that the following is red, the above is yellow, and the color in between is also orange between the two colors.

The discoloration range of methyl orange is PH "red, PH > yellow, and orange.

4.The reason for the discoloration of litmus test strips is basically the same as the cause of discoloration of ph test strips that I just explained, or the principle. Litmus is an organic substance with color reaction, which turns red when exposed to acid and blue when exposed to alkali.

Red litmus test paper is used to detect alkaline substances, and turns blue when alkaline; Blue litmus test paper is used to detect acids, which turn red when exposed to acid.

5.Regarding the comparison of acidity, what I can be sure of is (sulfuric acid, nitric acid) >phosphoric acid", acetic acid, carbonic acid, hypochlorous acid, silicic acid, and phenol, which can be judged by comparing the hydrogen ion dissociation constant, but since I guess you are a high school student, I don't think there is any need to be so fine, master two: a) strong acid to weak acid, remember a few metathesis reactions by the way, remember the acidity strength, such as the reaction of sodium phenol through CO2 to produce phenol, you can determine that the acidity of carbonic acid is stronger than phenol; b) Sulfuric acid, hydrochloric acid, nitric acid, perchloric acid, hydroiodic acid, and hydrobromic acid are strong acids, and there is no need to make the acidity ratio between them so clear, and there will be no such test.

6.About learning chemistry well.

Let's figure out all the knowledge in the textbook, chemistry is more dependent on memorization, there is nothing in the brain that is not good to learn, and when everything is memorized, I still feel that I can't learn well, and it is not too late to ask the question of how to learn chemistry.