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A radioactive metal, lawrencium is the eleventh transuranium element, the third transfermium, and the last member of the actinide series. Like all elements with atomic number over 100, lawrencium can only be produced in particle accelerators by bombarding lighter elements with charged particles.
Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 10 15 tonnes). [19] [70] [d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O
Oxygen is thus limited to a maximum +2 state, exhibited in the fluoride OF 2. The +4 state is known for sulfur , selenium , tellurium , and polonium, undergoing a shift in stability from reducing for sulfur(IV) and selenium(IV) through being the most stable state for tellurium(IV) to being oxidizing in polonium(IV).
The chemical properties of nobelium and lawrencium were studied with 255 No (t 1/2 = 3 min) and 256 Lr (t 1/2 = 35 s). The longest-lived nobelium isotope, 259 No, has a half-life of approximately 1 hour. [57] Lawrencium has 14 known isotopes with mass numbers 251–262, 264, and 266. The most stable of them is 266 Lr with a half life of 11 hours.
A period 2 element is one of the chemical elements in the second row (or period) of the periodic table of the chemical elements.The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases; a new row is started when chemical behavior begins to repeat, creating columns of elements with similar properties.
Very little is known about lawrencium, but calculations suggest it continues the trend of its lighter congeners toward increasing density. [62] [63] Scandium, yttrium, and lutetium all crystallize in the hexagonal close-packed structure at room temperature, [64] and lawrencium is expected to do the same. [65]
Triatomic oxygen (ozone, O 3) is a very reactive allotrope of oxygen that is a pale blue gas at standard temperature and pressure. Liquid and solid O 3 have a deeper blue color than ordinary O 2, and they are unstable and explosive. [5] [6] In its gas phase, ozone is destructive to materials like rubber and fabric and is damaging to lung tissue ...
However, the relative atomic mass of each isotope is quite close to its mass number (always within 1%). The only isotope whose atomic mass is exactly a natural number is 12 C, which has a mass of 12 Da; because the dalton is defined as 1/12 of the mass of a free neutral carbon-12 atom in the ground state.