H (Hydrogen), He (Helium), Li (Lithium), Be (Beryllium), B (Boron)
C (Carbon), N (Nitrogen), O (Oxygen), F (Fluorine), Ne (Neon)
Na (Sodium), Mg (Magnesium), Al (Aluminium), Si (Silicon),
P (Phosphorous), S (Sulphur), Cl (Chlorine), Ar (Argon),
K (Potassium, Ca (Calcium)
Element P (phosphorus) has a lower first ionization energy than element S (sulfur).
Because U is the first letter of the name uranium.
The name of the first scientist who used the term element was Johan Gadolin in the year 1760.
Uranium is the first element known to be radioactive. It was discovered by Henri Becquerel in 1896.
That depends on whether it is an ionic or covalent compound. If ionic, the first element has the same name as the element or ion, e.g. NaCl is sodium chloride; NH4Cl is ammonium chloride. If the compound is covalent, then the first element either retains its original name or has a prefix to denote the number of atoms of that element. For example, CO2 is carbon dioxide; P2O5 is di phosphorous pentoxide.
Calcium has twenty protons and twenty electrons. The main isotope of calcium also has twenty neutrons.
The oxidation number of an element is the charge that atom has when it forms ions. The oxidation number varies depending on the compound the element is in. There isn't a strict rule for the oxidation numbers of the first twenty elements as they can exhibit various oxidation states depending on the specific compound they are present in.
The first twenty element compounds would be combinations of elements that form chemical compounds consisting of those first twenty elements on the periodic table: hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, and calcium.
The 29th element is copper.
Cobalt
It is calcium.
It is twenty first floor.
No, there is no hyphen in "twenty-first century." When used as an adjective, it is written as "twenty-first," but when referring to the era as a noun, it is simply "twenty-first century" without a hyphen between "twenty" and "first."
''CA" (CAlCiUM)
The twenty seventh element in the periodic table is Cobalt, which has the symbol Co and atomic number 27. It is a transition metal that is commonly used in alloys and batteries.
The element with 26 electrons and protons is iron (Fe).
nope, twenty-first century is fine