Second, atoms are uncharged and electrons are negatively charged; There are protons and neutrons in the nucleus, protons are charged and neutrons are uncharged.
3. The density of the nucleus is so high that the electron mass can be ignored. The atomic volume is determined by the number of outer electron layers, and the mass is determined by the number of neutrons and protons in the nucleus.
1. Scientists in China obtained the atomic resolution image of hydrated sodium ions for the first time.
2.2065438+In May 2008, Xu and Gao of Peking University Quantum Materials Science Center cooperated with China Academy of Sciences/Wang Enge of Peking University, and made another breakthrough after obtaining the world's first sub-molecular resolution image of water molecules on 20 14, and obtained the atomic resolution image of hydrated sodium ions for the first time, and found the magic number effect of hydrated ion transport. The research results were published in the top international academic journal Nature on May 14, Beijing time.
3. Because water is a strong polar molecule, it can dissolve many salts as solvents and combine with dissolved ions to form clusters. This process is called ionic hydration, and the formed ionic hydration clusters are called ionic hydrates. Ionized water plays an important role in many physical, chemical and biological processes, such as salt dissolution, electrochemical reaction, ion transfer in life, air pollution, seawater desalination and corrosion.
4. The microstructure and kinetics of ionic hydrate have always been the focus of academic debate and research. Among them, how to obtain a single ion hydrate and get its stable image are two major problems. After continuous attempts and explorations, the research team overcame technical difficulties, obtained atomic resolution imaging for the first time, and successfully determined its atomic adsorption configuration by combining first-principles calculation and atomic force image simulation.
Scientists in China obtained the atomic resolution image of hydrated sodium ions for the first time (innovative frontier)-People's Daily Online