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प्रश्न
Give reasons for the following statement:
\[\ce{Zn}\], \[\ce{Cd}\] and \[\ce{Hg}\] are soft metals.
\[\ce{Zn}\], \[\ce{Cd}\] and \[\ce{Hg}\] are soft metals. Why?
उत्तर
Metal atoms like \[\ce{Zn}\], \[\ce{Cd}\] and \[\ce{Hg}\] have completely filled d-orbitals (d10 configuration). Thus, d-electrons are not available for metallic bond formation. As a result, these metals are quite soft and also have low melting points.
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संबंधित प्रश्न
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`MnO_4^(-) + H_2O + I^(-) ->`
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Match List - I with List - II.
| List - I | List - II | ||
| (a) | \[\ce{[Fe(CN)6]^3-}\] | (i) | 5.92 BM |
| (b) | \[\ce{[Fe(H2O)6]^3+}\] | (ii) | 0 BM |
| (c) | \[\ce{[Fe(CN)6]^4-}\] | (iii) | 4.90 BM |
| (d) | \[\ce{[Fe(H2O)6]^2+}\] | (iv) | 1.73 BM |
Choose the correct answer from the options given below.
Give reason for the following statement:
[Ti(H2O)]3+ is coloured while [Sc(H2O)6]3+ is colourless.
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The electrode potential of M2+/M of 3d-series elements shows the positive value for ______.
Account for the following:
Sc3+ is colourless whereas Ti3+ is coloured in an aqueous solution.
