Chemical elements are the basic components of matter. At present, the known chemical elements are 1 18 * *. Each element consists of a specific nucleus and a corresponding number of electrons, which are arranged by atomic number in the periodic table.
The following details the 26 elements in junior high school chemistry:
Hydrogen (H): The chemical symbol is H, which is one of the most abundant elements in the universe. The element with atomic number 1 is the lightest element. Hydrogen usually exists in the form of gas and is widely used in hydrogen energy and industrial chemical reactions.
Helium (He): The chemical symbol is He, which is a nonmetallic inert gas. It is the second lightest element with low density, low solubility and extremely low boiling point. Helium is widely used in balloons, laser technology and coolers.
Lithium (Li): The chemical symbol is Li, which is an alkali metal element. It has low density, high melting point and high activity. Lithium has important applications in battery manufacturing, alloy preparation and nuclear reactor.
Be: The chemical symbol is Be, which is an alkaline earth metal element. It is a light and hard metal with good thermal conductivity. Beryllium is widely used in aerospace, electronic equipment and nuclear industry.
Boron (B): chemical symbol is B, which is a semi-metallic element. It has high melting point, low density and good conductivity. Boron plays an important role in glass manufacturing, metallurgy and chemical reaction catalysts.
Carbon (C): The chemical symbol is C, which is a nonmetallic element. Carbon exists in many forms in nature, such as diamond, graphite and total carbon. Carbon is the basis of organic chemistry, which constitutes the basic molecule of life in organisms.
Nitrogen (N): The chemical symbol is N, which is a nonmetallic element. Nitrogen is one of the main components in the air, which has stability and high reactivity. Nitrogen is widely used in fertilizer production, chemical industry and high-energy escape propellant.
Oxygen (O): The chemical symbol is O, which is a nonmetallic element. Oxygen is one of the most common elements on the earth, and most living things need oxygen to breathe. Oxygen is widely used in combustion, oxidation reaction and medical industry.
Fluorine (F): The chemical symbol is F, which is a very active nonmetallic element. Fluorine is used as a catalyst in the chemical industry and is also added to drinking water and toothpaste to prevent dental caries.
Sodium (Na): The chemical symbol is Na, which is an alkali metal element. It is one of the most common elements in the earth's crust and can form salts with chlorine. Sodium is widely used in food processing, metallurgy and preparation of other compounds.
Magnesium (Mg): The chemical symbol is Mg, which is an alkaline earth metal element. Magnesium has low density, high strength and good corrosion resistance. Magnesium has important applications in aerospace, fuel cells and alloy preparation.
Aluminum (Al): The chemical symbol is Al, which is a light and hard metal. Aluminum has good thermal conductivity and corrosion resistance. Aluminum is widely used in construction, packaging and electronic industry.
Silicon (Si): The chemical symbol is Si, which is a semi-metallic element. Silicon is the second most abundant element in the earth's crust, which is widely used in glass manufacturing, semiconductors and solar cells.
Phosphorus (P): The chemical symbol is P, which is a nonmetallic element. Phosphorus plays a key biochemical role in organisms and is also used to prepare fertilizers, drugs and detergents.
Sulfur (S): The chemical symbol is S, which is a nonmetallic element. Sulfur exists in many forms, such as sulfur and sulfuric acid. Sulfur has important applications in chemical synthesis, petroleum processing and soap manufacturing.
Chlorine (Cl): The chemical symbol is Cl, which is a nonmetallic element. Chlorine is a common element in the earth's crust and is widely used as disinfectant, plastic and raw material for pharmaceutical industry.
Potassium (K): The chemical symbol is K, which is an alkali metal element. Potassium plays an important role in organisms and is widely used in the manufacture of fertilizers, glass and soap.
Calcium (Ca): Chemical symbol is Ca, which is an alkaline earth metal element. Calcium is an important part of bones and teeth, and it is also widely used in metallurgy and construction industry.
Manganese (Mn): The chemical symbol is Mn, which is a transition metal element. Manganese is widely used in steel production, battery manufacturing and catalyst.
Iron (Fe): The chemical symbol is Fe, which is a transition metal element. Iron is one of the most common elements in the earth's crust, which is widely used in construction, manufacturing and magnetic materials.
Nickel (Ni): The chemical symbol is Ni, which is a transition metal element. Nickel is widely used in alloys, batteries and catalysts because of its corrosion resistance and magnetism.
Copper (Cu): The chemical symbol is Cu, which is a transition metal element. Copper has good electrical and thermal conductivity and is widely used in electrical equipment, pipelines and alloy preparation.
Zinc (Zn): The chemical symbol is Zn, which is a transition metal element. Zinc has good corrosion resistance and is widely used in zinc plating, battery and alloy preparation.
Silver (Ag): The chemical symbol is Ag, which is a transition metal element. Silver has good electrical conductivity and antibacterial properties, and is widely used in jewelry, photography and electronic equipment.
Platinum (Pt): The chemical symbol is Pt, which is a transition metal element. Platinum has high corrosion resistance and is widely used in chemical catalysts, jewelry and electronic equipment.
Gold (Au): The chemical symbol is Au, which is a transition metal element. Gold has good electrical conductivity and corrosion resistance, and is widely used in jewelry, currency and electronic equipment.
To quickly remember the 26 elements of junior high school chemistry, you can try the following methods:
Use mnemonic method: associate each element with its related key features or vocabulary to help remember. For example, oxygen (O) can be associated with "oxygen", "breathing" and so on.
Making a memory card: Write down the symbols and names of components on a card, and read and write them repeatedly until you can remember them skillfully.
Grouping memory: grouping elements according to a certain classification, such as alkali metals, alkaline earth metals, semi-metals, etc. Remember the element characteristics of each group, and similar elements together will help to deepen the memory.
Making the chemical periodic table: copy or print the periodic table, paste it in the common study place, browse it several times a day, and gradually get familiar with the arrangement order of elements.
Making associative images: transforming the symbols and names of each element into concrete images or visual memory points, and connecting them in series to form an interesting and unforgettable story.
Repeated review: consolidate memory through continuous review and review. You can use your spare time to review quickly, such as on the bus, waiting in line, etc.