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The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of Cr^3+ ion is ______. - Chemistry

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प्रश्न

The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of \[\ce{Cr^{3+}}\] ion is ______.

विकल्प

  • 2.87 B.M.

  • 3.87 B.M.

  • 3.47 B.M.

  • 3.57 B.M.

MCQ
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उत्तर

The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of \[\ce{Cr^{3+}}\] ion is 3.87 B.M..

Explanation:

\[\ce{Cr -> (Z = 24)}\]

\[\ce{Cr^{3+} -> (Z = 21)}\]

\[\ce{1s^2 2s^2 2P^6 3s^2 3p^6 3d^3 4s^0}\]

n = 3(3 unpaired electrons)

`mu = sqrt(n(n + 2))`

`mu = sqrt(3(3 + 2))`

`mu = sqrt(3(5))`

`mu = sqrt(15)` = 3.87 B.M.

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अध्याय 8: The d-and f-Block Elements - Multiple Choice Questions (Type - I) [पृष्ठ १०८]

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एनसीईआरटी एक्झांप्लर Chemistry [English] Class 12
अध्याय 8 The d-and f-Block Elements
Multiple Choice Questions (Type - I) | Q 15 | पृष्ठ १०८

संबंधित प्रश्न

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The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10


Transition elements form binary compounds with halogens. Which of the following elements will form \[\ce{MF3}\] type compounds?

(i) \[\ce{Cr}\]

(ii) \[\ce{Co}\]

(iii) \[\ce{Cu}\]

(iv) \[\ce{Ni}\]


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(a) \[\ce{Co}\]
(ii) Element with highest
third ionisation enthalpy
(b) \[\ce{Cr}\]
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(iv) Element with highest heat
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Reason (R): Because it has positive electrode potential.


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\[\ce{MO3F}\]


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Read the passage given below and answer the following question.

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.

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