Mass-to-charge ratio refers to the molecular or atomic mass number and "z" to the charge number of the ion; however, the quantity of "m"/"z" is dimensionless by definition. An ion of 100 atomic mass units ("m" = 100) carrying two charges ("z" = 2) will be observed at "m"/"z" = 50. In the 19th century, the mass-to-charge ratios of some ions were measured by electrochemical methods. In 1897, the mass-to-charge ratio of the electron was first measured by J. J. Thomson. By doing this, he showed that the electron was in fact a particle with a mass and a charge, and that
Kelsey (given name) in 1996. It was the 528th most common name for women in the United States in the 1990 census. Kelsey was ranked among the top 100 names for girls born in Scotland in 2007. It was also among the top 100 names for girls born in England and Wales in the late 1990s. People with the given name Kelsey: Kelsey (given name) Kelsey Is a unisex given name of English origin. The name most probably derives from an Old English given name "Ceolsige", which meant "ship's victory", or it could be a place name meaning "Cenel's island". "Cenel's Island" is