- Chinatown, San Francisco (Wikipedia)
The Chinatown centered on Grant Avenue and Stockton Street in San Francisco, California, (Chinese: 唐人街; pinyin: tángrénjiē; Jyutping: tong4 jan4 gaai1) is the oldest Chinatown in North America and one of the largest Chinese enclaves outside Asia. It is also the oldest and largest of the four notable Chinese enclaves within San Francisco. Since its establishment in the early 1850s, it has been important and influential in the history and culture of ethnic Chinese immigrants in North America. Chinatown is an enclave that has retained its own customs, languages, places of worship, social clubs, and identity.
- Ion (Wikipedia)
An ion (/ˈaɪ.ɒn, -ən/) is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons.