Chemical product changes and pet coke price of goods

pet coke price is so cheap here: What is wrong with the following statement is () A. Atoms can directly form substance B. Molecules can be subdivided, atoms can't be subdivided into C. In a chemical reaction, the molecule changes but the atom does not, indicating that the molecule is in motion and the atom is at rest. Water molecules maintain the chemical properties of water solution: both molecules and atoms can directly constitute matter, molecules are composed of atoms, atoms can be divided into protons and neutrons. Molecules are the smallest particles that hold the chemical properties of a substance. Molecules and atoms all move irregularly. 2

Basic concepts: 1, chemical change: the change of other substances; 2, physical change: no change of other substances; 3, physical properties: no chemical change is required to show the nature (such as: color, state, density, odor, melting point, boiling point, hardness, water solubility, etc.) The properties of substances shown in chemical changes (such as: flammability, combustibility, oxidation, reducibility, acid and alkali, stability, etc.) 

5, pure matter: composed of a material 6, mixture: composed of two or more pure matter, each substance maintains its original properties 7, elements: with the same nuclear charge number (that is, the number of protons) of a class of atoms general name 8, atoms: Is the smallest particle in the chemical change, in the chemical change can not be divided 9, molecule: is to maintain the chemical properties of the smallest particle, in the chemical change can be divided 10, elemental: pure matter composed of the same element 11, compound: pure matter composed of different elements 12, oxide: In a compound composed of two elements, one of which is oxygen 13, chemical formula: The formula used to represent the composition of substances by the symbols of the elements 

14, relative atomic mass: With the mass of a carbon atom 1/12 as the standard, the mass of other atoms compared with it the value of an atom relative atomic mass = relative atomic mass ≈ number of protons + number of neutrons (because the mass of the atom is mainly concentrated in the nucleus) 15, relative molecular mass: the sum of the relative atomic mass of the atoms in the chemical formula 16, ions: 17, the structure of the atom: the relationship between atoms and ions: Note: in ions, the number of nuclear charge = the number of protons ≠ the number of electrons in the nucleus 18, the four basic types of chemical reactions: 1 combination reaction: the reaction of two or more substances to form a substance