Chemistry (Wikipedia)
Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during reactions with other substances. Chemistry also addresses the nature of chemical bonds in chemical compounds.- Sulfur (also spelled sulphur in British English) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with the chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature.
- China (Wikipedia)
China (Chinese: 中国; pinyin: Zhōngguó), officially the People’s Republic of China (PRC), is a country in East Asia. It is the world’s second-most populous country, with a population exceeding 1.4 billion. China spans the equivalent of five time zones and borders fourteen countries by land, tied with Russia as having the most of any country in the world. With an area of nearly 9.6 million square kilometres (3,700,000 sq mi), it is the world’s third largest country by total land area. The country consists of 22 provinces, five autonomous regions, four municipalities, and two special administrative regions (Hong Kong and Macau). The national capital is Beijing, and the most populous city and largest financial center is Shanghai.
- Chlorine (Wikipedia)
Chlorine is a chemical element; it has symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine.
- Phosphorus (Wikipedia)
Phosphorus is a chemical element; it has symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth’s crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate.