Out of C and CO, which is a better reducing agent at the lower temperature range in the blast furnace to extract iron from the oxide ore?
What happens when
(i) PCl5 is heated?
(ii) H3PO3 is heated?
Write the reactions involved ?
Which metal in the first transition series (3d series) exhibits + 1 oxidation state most frequently and why?
Which of the following cations are coloured in aqueous solutions and why?
Sc3+, V3+, Ti4+, Mn2+ (Atomic number Sc = 21, V = 23, Ti = 22, Mn = 25)
The colour of cations is dependent on the number of unpaired electrons present in d-orbital. The electronic configuration of the following cations is as follows:
Sc (Atomic number 21) = 3d1 4s2 and Sc3+ = 3d0 4s0. As d-orbital is empty, it is colourless.
V (Atomic number 23) = 3d3 4s2 and V3+ = 3d2 4s0. As d-orbital is having 2 unpaired electrons, it undergoes d-d transition and shows green colour
Ti = (Atomic number 22) = 3d2 4s2 and Ti4+ = 3d0 4s0. As d-orbital is empty, it is colourless
Mn = (Atomic number 25) = 3d5 4s2 and Mn2+ = 3d5 4s0. As d-orbital is having 5 unpaired electrons, it shows pink color.
(a) What type of semiconductor is obtained when silicon is doped with boron?
(b) What type of magnetism is shown in the following alignment of magnetic moments?
(c) What type of point defect is produced when AgCl is doped with CdCl2?
Determine the osmotic pressure of a solution prepared by dissolving 2.5 x 10-2 g of K2SO4 in 2L of water at 250C, assuming that it is completely dissociated.
(R = 0.0821 L atm K-1 mol-1, Molar mass of K2SO4 = 174 g mol-1)
How would you account for the following?
(i) Transition metals exhibit variable oxidation states.
(ii) Zr (Z = 40) and Hf (Z = 72) have almost identical radii.
(iii) Transition metals and their compounds act as catalystWrite the IUPAC names of the following coordination compounds:
(i) [Cr(NH3)3Cl3]
(ii) K3[Fe(CN)6]
(iii) [CoBr2(en)2]+, (en = ethylenediamine)