Which ion with a +2 charge has the electron configuration?
1s2 2s2 2p6

Measuring which physical property is most likely to produce the most precise results when trying to identify a substance

How to convert a density of 0.791g/cm3 to lb/ft3

In the cathode ray tube experiment, j. j. thomson passed an electric current through different gases inside a cathode ray tube in the presence of an electric field. in which two ways did this experiment change scientists’ understanding of the atom?