Learning Problems in Chemistry Come and help Horn, thank you Lak.

The knowledge points of chemistry are very scattered, so I think it is difficult to remember, but in fact, high school chemistry can be summarized into several pieces, it is best to find your own teacher to help summarize it, and then find your weak links and then focus on overcoming, so that you can improve faster, for example, if you are poor in redox reaction, then read more books, figure out the principle of redox reaction, and then do questions to consolidate and so on. It's been many years since I graduated, and that's how our teacher taught us at that time, and I thought it was very good, but now I forget how to classify it, and I don't dare to talk nonsense, because if I say it wrong, I will be wrong.

Get a tutor or find a class and take the time to start over.

I don't think it's very useful, but if you find it useful, you can ask for it.

I think you have to memorize chemistry well, especially those basic content, special cases, and commonly used things (formulas, some chemical equations, etc.), and do more questions and pay attention to details.

I'm a freshman in high school, and my chemistry is pretty good, around 80

I think you should review equations and theories, preferably with a lot of association, at least that's how I learned

Chemistry knowledge is relatively fragmented, and there are many things that need to be memorized, and what should be memorized must be remembered once and for all.

Chemistry is a discipline with strong regularity, and we should think more, discover more and summarize more in the learning process.

As a science subject, it is necessary to do more questions. Old.

Chemistry is actually very easy, master the method, listen to the lectures well, read the book carefully, there is no problem.

It's nothing more than a test of a few equations over and over, and you can also summarize that chemistry questions are just a few equations. So, don't think that chemistry is difficult to learn, it's much easier than math and physics

1.Check that the following chemical formulas are correct, and correct the wrong chemical formulas.

Sodium oxide. nao

Na2O calcium oxide. oca

CAO alumina. alo

_al2o3

Calcium hydroxide. ohk

_ca（oh)2

Magnesium hydroxide. mgho

_mg（oh)2

Iron hydroxide. feoh

fe（oh)3

Mainly memorize the valency of various ions and how to write them.

2.One of the main materials for high-performance magnetic particles used in video tapes is a compound composed of three elements: Co, Fe and O, and its chemical formula is Co(X)Fe(3-X)O(3+X)Oxygen is known to be -2 valence, CO and iron may exhibit +2 or +3 valence, and there is only one valency of each element in the above compounds, then the value of x is (1, the valency of iron is (+3, and the valency of CO is (+2