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Anonymous users2024-02-07You leave a QQ, I will send it to you, I am a junior high school chemistry teacher in Suzhou.
Chapter 3: The Mystery of the Composition of Matter.
1. Many experiments have shown that matter is made up of extremely tiny things that are invisible to the naked eye.
2. Walk into the garden and smell the flowers; Explain the particles that make up the substance
ml of water and 50 ml of alcohol are mixed, and the total volume is less than 100 ml instructions
4. (p63) Scientists have confirmed for a long time that the particles that make up the matter are composed of atoms, such as diamond; Some substances are made up of ions, such as table salt, which is made up of ; There are also substances that are made up of molecules, such as dry ice.
5. Molecules are made up, and in chemical change, molecules are first divided into atoms and then recombined to form new ones (please use this method to analyze the process by which water decomposes to hydrogen and oxygen under electrified conditions p65 first line).
6. (p65) Our common and are directly composed of atoms. In the course of human understanding of the atom, p66) proposed the atomic theory.
7. (67 68) Scientists have found that atoms are made up of charged and charged people. The electric charge carried by both is electrical, and thus the atom is sexual. The nucleus is the body positive that occupies the atom
But the nucleus of the atom is almost concentrated and British scientists have confirmed that the atom contains electrons. The existence of is confirmed by particle scattering experiments.
Scientists have also discovered that the nucleus is made up of and , where there is no electric charge. __=___=___
Relative atomic mass
8. (p68) is called the relative atomic mass of such atoms. The relative molecular mass is
9. (p69) In chemical change This charged particle is called
10. (P73) Be proficient in writing the 20 element symbols on this page.
Hydrogen, carbon, nitrogen, oxygen, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, calcium, manganese, iron, copper, zinc, silver, iodine, mercury
11, (p74) is called elemental, e.g. is called compound, e.g
12. (p75) The order of the content of elements in the earth's crust from large to small The order of the content of elements in the ocean The order of the content of elements in the human body The most abundant elements in the sun are
13. The lack of certain elements in the human body will affect health and even cause diseases. For example, deficiency may lead to rickets; Deficiency can lead to stunted growth in children and severe dwarfism; Deficiency susceptibility to anemia; Deficiency can lead to thyroid disease.
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Anonymous users2024-02-06The main point of learning is equations and knowledge points. The score of the equation station is 70%, so try to memorize the equations, many equations are regular. There is also the use of equations to set unknowns and calculate.
Remember one thing: the solution list calculates. The solution is the beginning, "Solution:, this is a point, let is let be an unknown, the column is a column equation, the table is a representation, it is a calculation, and the answer is the final answer." Remember.
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Weigh the weight of the front and rear B device. On the small side.
Chemistry knowledge points in the third year of junior high school are: >>>More