although elements are pure substances but why chromate ,aluminate,silicate etc considered as elements and how there valency is determined
Answers
Answer:
Explanation:
yes it is
Answer:
plz mark as brainliest
Explanation:
1A 2A 3A 4A 5A 6A 7A 8A
(1) (2) (13) (14) (15) (16) (17) (18)
3B 4B 5B 6B 7B — 8B — 1B 2B
(3) (4) (5) (6) (7) (8) (9) (10) (11) (12)
1 H He
2 Li Be B C N O F Ne
3 Na Mg Al Si P S Cl Ar
4 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
5 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
6 Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
7 Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg Uub — Uuq — — — —
6 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
7 Th
The transition elements or transition metals occupy the short columns in the center of the periodic table, between Group 2A and Group 3A. They are sometimes called the d-block elements, since in this region the d-orbitals are being filled in, and are also referred to as B-group elements since in most numbering systems of the columns on the periodic table the numerals of these groups are followed by the letter B. The period 4 transition metals are scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), and zinc (Zn). The period 5 transition metals are yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), and cadmium (Cd). The period 6 transition metals are lanthanum (La), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), and mercury (Hg). The period 7 transition metals are the naturally-occurring actinium (Ac), and the artificially produced elements rutherfordium (Rf), dubnium (Db), seaborgium (Sg), bohrium (Bh), hassium (Hs), meitnerium (Mt), darmstadtium (Ds), roentgenium (Rg), and the as-yet unnamed ununbiium (Uub).
The elements which follow lanthanum (Z=57) and actinium (Z=89) are called the lanthanides and actinides, respectively, and together are known as the inner transition elements.
In the transition metals, the five d orbitals are being filled in, and the elements in general have electron configurations of (n-1)d1-10 ns2, although there are some exceptions when electrons are shuffled around to produce half-filled or filled d subshells. Many of the transition metals can lose two or three electrons, forming cations with charges of 2+ or 3+, but there are some which form 1+ charges, and some which form much higher charges.
All of the transition metals in their elemental forms are malleable and ductile (except for mercury, which is a liquid at room temperature), and are good conductors of heat and electricity. Many of the transition metal ions have characteristic colors associated with them, and many have biological and industrial significance.
Group 3B (3)
The Group 3B elements (Group 3 in the IUPAC designation) usually have electron configuration (n-1)d1 ns2. In most periodic tables, lanthanum and actinium are considered to be a part of Group 3B, but in others lanthanum and actinium are considered part of the inner transition elements, leaving lutetium and lawrencium in Group 3B instead. Most of these elements form 3+ charges, although other oxidation states are known.
Scandium (Sc, Z=21)
Scandium is a soft, silvery metal. It is named from the Latin word for Scandinavia, Scandia. It is found in the Earth's crust at a concentration of 16 ppm, making it the 35th most abundant element. It is found in the ore thortveitite [Sc2Si2O7], and is present in small amounts in other ores.
Scandium is lightweight, resistant to corrosion, and even stronger than aluminum, but its rarity makes its production costly. Scandium's existence was predicted by Dimitri Mendeleev from a gap in his periodic table of the elements; when scandium was discovered in 1879, its properties were close to those predicted by Mendeleev. There are few known compounds of scandium. Scandium iodide, ScI3, is used in mercury vapor lamps to produce a light that is closer to that of natural sunlight.
of origin.