The atomic number of an element is equal to the total number of protons in the nucleus of the atoms of that element. The atomic number can provide insight into the electronic configuration of the element. For example, carbon has an electron configuration of He 2s 2 2p 2, since its atomic number is 6. List of Elements in Atomic Number Order¶. The names and symbols for elements 112-118 are under review. The temporary system recommended by J Chatt, Pure Appl. Chem., 51, 381-384 (1979) is used above. Boron is a chemical element with atomic number 5 which means there are 5 protons and 5 electrons in the atomic structure. The chemical symbol for Boron is B. Significant concentrations of boron occur on the Earth in compounds known as the borate minerals. The number of protons plus neutrons in the nucleus 2 electrons 2. Negative subatomic particles; symbolized by e- 4 isotope 3. Atom with a net charge caused by unequal numbers of electrons and protons 1 atomic mass or mass number 4. Same element but different mass number due to numbers of neutrons in the nucleus 5 radioactive.
The periodic table is an arrangment of the chemical elements ordered by atomic number so that periodic properties of the elements (chemical periodicity) are made clear.
Explore the chemical elements through this periodic table
Atomic Number 54
| Group | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Period 1 | Hydrogen | Helium | |||||||||||||||||
| 2 | Lithium | Beryllium | Boron | Carbon | Nitrogen | Oxygen | Fluorine | Neon | |||||||||||
| 3 | Sodium | Magnesium | Aluminium | Silicon | Phosphorus | Sulfur | Chlorine | Argon | |||||||||||
| 4 | Potassium | Calcium | Scandium | Titanium | Vanadium | Chromium | Manganese | Iron | Cobalt | Nickel | Copper | Zinc | Gallium | Germanium | Arsenic | Selenium | Bromine | Krypton | |
| 5 | Rubidium | Strontium | Yttrium | Zirconium | Niobium | Molybdenum | Tc☢ Technetium | Ruthenium | Rhodium | Palladium | Silver | Cadmium | Indium | Tin | Antimony | Tellurium | Iodine | Xenon | |
| 6 | Caesium | Barium | * | Lutetium | Hafnium | Tantalum | Tungsten | Rhenium | Osmium | Iridium | Platinum | Gold | Mercury | Thallium | Lead | Bismuth | Po☢ Polonium | At☢ Astatine | Rn☢ Radon |
| 7 | Fr☢ Francium | Ra☢ Radium | ** | Lr☢ Lawrencium | Rf☢ Rutherfordium | Db☢ Dubnium | Sg☢ Seaborgium | Bh☢ Bohrium | Hs☢ Hassium | Mt☢ Meitnerium | Ds☢ Darmstadtium | Rg☢ Roentgenium | Cn☢ Copernicium | Nh☢ Nihonium | Fl☢ Flerovium | Mc☢ Moscovium | Lv☢ Livermorium | Ts☢ Tennessine | Og☢ Oganesson |
| *Lanthanoids | * | Lanthanum | Cerium | Praseodymium | Neodymium | Pm☢ Promethium | Samarium | Europium | Gadolinium | Terbium | Dysprosium | Holmium | Erbium | Thulium | Ytterbium | ||||
| **Actinoids | ** | Ac☢ Actinium | Th☢ Thorium | Pa☢ Protactinium | U☢ Uranium | Np☢ Neptunium | Pu☢ Plutonium | Am☢ Americium | Cm☢ Curium | Bk☢ Berkelium | Cf☢ Californium | Es☢ Einsteinium | Fm☢ Fermium | Md☢ Mendelevium | No☢ Nobelium | ||||
The standard form of the periodic table shown here includes periods (shown horizontally) and groups (shown vertically). The properties of elements in groups are similar in some respects to each other.
Atomic Number 52
There is no one single or best structure for the periodic table but by whatever consensus there is, the form used here is very useful and the most common. The periodic table is a masterpiece of organised chemical information and the evolution of chemistry's periodic table into the current form is an astonishing achievement.