Report Abuse. X-radiation (composed of X-rays) is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3 Ã 1016 Hz to 3 Ã 1019 Hz) and energies in the range 120 eV to 120 keV.hen x-rays were first discovered, scientists didn't know much about them, so they called them X-rays because X in science is often used to designate an unknown as in Planet X or solve for X They were also sometimes called Rontgen Rays after the man who discovered them.
1. calcium ion-ion of calcium; a factor in the clotting of blood. factor IV. atomic number 20, Ca, calcium-a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals.. calcium ion-ion of calcium; a factor in the clotting of blood. factor IV. atomic number 20, Ca, calcium-a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals.
Calcium is the third element in the second column of the periodic table. It is classified as an alkaline earth metal. Calcium atoms have 20 electrons and 20 protons. There are 2 valence electrons in the outer shell. Calcium is an important element for life on Earth and is the fifth most abundant element in the Earth's crust. Under standard conditions calcium is a shiny, silvery metal. It is fairly soft and is the lightest of the alkaline earth metals due to its low density.