This answer is: Phosphorusis a chemical element withatomic number15which means there are 15 protons and 15 electrons in the atomic structure. Equally important is their low toxicity. Commercial use of the Images will be charged at a rate based on the particular use, prices on application. All isotopes of radium are highly radioactive, with the most stable isotope being radium-226. By mass, aluminium makes up about 8% of the Earths crust; it is the third most abundant element after oxygen and silicon and the most abundant metal in the crust, though it is less common in the mantle below. Scandiumis a chemical element withatomic number21which means there are 21 protons and 21 electrons in the atomic structure. Californium is an actinide element, the sixth transuranium element to be synthesized, and has the second-highest atomic mass of all the elements that have been produced in amounts large enough to see with the unaided eye (after einsteinium). Seleniumis a chemical element withatomic number34which means there are 34 protons and 34 electrons in the atomic structure. Zirconium metal is produced commercially by first converting zircon to zirconium chloride, and then reducing the chloride with magnesium. Chromium is a steely-grey, lustrous, hard and brittle metal4 which takes a high polish, resists tarnishing, and has a high melting point. Gems that contain zirconium were known in ancient times as zircon. Thechemical symbolfor Neodymium isNd. Titanium condenser tubes are usually the best technical choice, however titanium is very expensive material. Atomic number or Protons: 40: Neutrons: 51: Electrons: 40: Symbol: Zr: Atomic mass: 91.224 u: Electrons arrangement or . Hint: The given isotope is Zirconium-92 where the value 92 is the mass number of the zirconium atom. The metal is found in the Earths crust in the pure, free elemental form (native silver), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Nuclear Magic Numbers - Chemistry LibreTexts But its density pales by comparison to the densities of exotic astronomical objects such as white dwarf stars and neutron stars. Significant concentrations of boron occur on the Earth in compounds known as the borate minerals. Zirconium oxide is to be found in ultra-strong ceramics that are stronger and sharper even than toughened steel and are used for knives, scissors and golf irons. Lead is a heavy metal that is denser than most common materials. Zirconium metal is protected by a thin oxide layer making it exceptionally resistant to corrosion by acids, alkalis and seawater. Atoms of the same element with different numbers of neutrons. Lawrencium is the final member of the actinide series. Thechemical symbolfor Dysprosium isDy. Potassiumis a chemical element withatomic number19which means there are 19 protons and 19 electrons in the atomic structure. 2,8,20,28,50,82,114 (protons), 126 (neutrons), 184 (neutrons) are particularly stable in nuclei.