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प्रश्न
Match the properties given in Column I with the metals given in Column II.
| Column I (Property) | Column II (Metal) | |
| (i) | Element with highest second ionisation enthalpy |
(a) \[\ce{Co}\] |
| (ii) | Element with highest third ionisation enthalpy |
(b) \[\ce{Cr}\] |
| (iii) | \[\ce{M}\] in \[\ce{M(CO)6}\] is | (c) \[\ce{Cu}\] |
| (iv) | Element with highest heat of atomisation |
(d) \[\ce{Zn}\] |
| (e) \[\ce{Ni}\] |
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उत्तर
| Column I (Property) | Column II (Metal) | |
| (i) | Element with highest second ionisation enthalpy |
(c) \[\ce{Cu}\] |
| (ii) | Element with highest third ionisation enthalpy |
(d) \[\ce{Zn}\] |
| (iii) | \[\ce{M}\] in \[\ce{M(CO)6}\] is | (b) \[\ce{Cr}\] |
| (iv) | Element with highest heat of atomisation |
(a) \[\ce{Co}\] |
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संबंधित प्रश्न
Which of the 3d series of the transition metals exhibits the largest number of oxidation states and why?
Why are Mn2+ compounds more stable than Fe2+ towards oxidation to their +3 state?
To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.
Which of the d-block elements may not be regarded as the transition elements?
How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.
Predict which of the following will be coloured in the aqueous solution?
Ti3+, V3+, Cu+, Sc3+, Mn2+, Fe3+ and Co2+. Give reasons for each.
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Electronic configurations
Write the factors which are related to the colour of transition metal ions.
NF3 is possible, but NF5 is not. Why?
Why EΘ values for Mn, Ni and Zn are more negative than expected?
Explain why does colour of KMnO4 disappear when oxalic acid is added to its solution in acidic medium.
Transition metals can act as catalysts because these can change their oxidation state. How does \[\ce{Fe(III)}\] catalyse the reaction between iodide and persulphate ions?
Fill in the blanks by choosing the appropriate word(s) from those given in the brackets:
(activation energy, Threshold energy, increased, lowered, partially, full, d-d transition, Benzoic acid, benzaldehyde)
Only those transition metal ions will be coloured which have ______ filled d-orbitals facilitating ______.
Read the passage given below and answer the following question.
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Are there nuclear reactions going on in our bodies? There are nuclear reactions constantly occurring in our bodies, but there are very few of them compared to the chemical reactions, and they do not affect our bodies much. All of the physical processes that take place to keep a human body running are chemical processes. Nuclear reactions can lead to chemical damage, which the body may notice and try to fix. The nuclear reaction occurring in our bodies is radioactive decay. This is the change of a less stable nucleus to a more stable nucleus. Every atom has either a stable nucleus or an unstable nucleus, depending on how big it is and on the ratio of protons to neutrons. The ratio of neutrons to protons in a stable nucleus is thus around 1 : 1 for small nuclei (Z < 20). Nuclei with too many neutrons, too few neutrons, or that are simply too big are unstable. They eventually transform to a stable form through radioactive decay. Wherever there are atoms with unstable nuclei (radioactive atoms), there are nuclear reactions occurring naturally. The interesting thing is that there are small amounts of radioactive atoms everywhere: in your chair, in the ground, in the food you eat, and yes, in your body. The most common natural radioactive isotopes in humans are carbon-14 and potassium-40. Chemically, these isotopes behave exactly like stable carbon and potassium. For this reason, the body uses carbon-14 and potassium-40 just like it does normal carbon and potassium; building them into the different parts of the cells, without knowing that they are radioactive. In time, carbon-14 atoms decay to stable nitrogen atoms and potassium-40 atoms decay to stable calcium atoms. Chemicals in the body that relied on having a carbon-14 atom or potassium-40 atom in a certain spot will suddenly have a nitrogen or calcium atom. Such a change damages the chemical. Normally, such changes are so rare, that the body can repair the damage or filter away the damaged chemicals. The natural occurrence of carbon-14 decay in the body is the core principle behind carbon dating. As long as a person is alive and still eating, every carbon-14 atom that decays into a nitrogen atom is replaced on average with a new carbon-14 atom. But once a person dies, he stops replacing the decaying carbon-14 atoms. Slowly the carbon-14 atoms decay to nitrogen without being replaced, so that there is less and less carbon-14 in a dead body. The rate at which carbon-14 decays is constant and follows first order kinetics. It has a half-life of nearly 6000 years, so by measuring the relative amount of carbon-14 in a bone, archeologists can calculate when the person died. All living organisms consume carbon, so carbon dating can be used to date any living organism, and any object made from a living organism. Bones, wood, leather, and even paper can be accurately dated, as long as they first existed within the last 60,000 years. This is all because of the fact that nuclear reactions naturally occur in living organisms. |
Why is Carbon-14 radioactive while Carbon-12 not? (Atomic number of Carbon: 6)
The spin magnetic moment of cobalt in the compound Hg [Co(SCN)4] is:-
The product of oxidation of I– with \[\ce{MnO^{-}4}\] in alkaline medium is:-
Agcl is soluble in NH4OH. The solubility is due to the information of:-
Account for the following:
Sc3+ is colourless whereas Ti3+ is coloured in an aqueous solution.
Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)
The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.
