Hydrogen doesn’t fit into this grouping and is placed over the table, this is because of Hydrogen's atomic structure. The first 94 chemical elements, up to plutonium, occur naturally on Earth ...

The fundamental data structure in a data processing system. Any unit of data defined for processing is a data element; for example, ACCOUNT NUMBER, NAME, ADDRESS and CITY. A data element is ...

IT has been shown by one of us 1 that, at ordinary temperatures, the structure of nickel oxide is slightly deformed from face-centred cubic symmetry. Later work 2 proved that at − 180° C.

Promethium’s short half-life and lack of stable isotopes makes it difficult to study. In addition, promethium is difficult to ...