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
Cassidy (given name) Cassidy (given name) Cassidy is a given name derived from an Irish surname and ultimately from the Gaelic given name "Caiside", meaning "clever" or "curly-haired." The name "Caiside" comes from the Gaelic word element "cas", according to "Behindthename.com" Cassidy was the 244th most popular name for girls born in the United States in 2009. It was most popular in 1999, when it was the 99th most popular name for American girls. It first appeared among the 1,000 most popular names for American girls in 1981. Kassidy, an alternate spelling, was ranked as the 443rd most popular name for girls in