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प्रश्न
What is ferromagnetism?
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उत्तर
- Ferromagnetism is a property of certain materials in which the atoms have unpaired electrons whose spins align parallel to each other, resulting in a strong, permanent magnetic moment.
- The substances that can be permanently magnetised even in the absence of a magnetic field are called ferromagnetic substances, and the mechanism is called ferromagnetism.
- Some examples of ferromagnetic substances are iron, cobalt, nickel, gadolinium, and CrO2.
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संबंधित प्रश्न
Iron (z=26) is highly ferromagnetic. Explain.
What type of magnetism is shown in the following alignment of magnetic moments?
What type of magnetism is shown by a substance if magnetic moments of domains are arranged in same direction?
Define the following term:
Ferromagnetism
Write the type of magnetism observed when the magnetic moments are oppositely aligned and cancel out each other.
Write the type of magnetism observed when the magnetic moments are aligned in parallel and anti-parallel directions in unequal numbers.
What type of substances would make better permanent magnets, ferromagnetic or ferrimagnetic. Justify your answer.
Analysis shows that nickel oxide has the formula Ni0.98O1.00. What fractions of nickel exist as Ni2+ and Ni3+ ions?
Explain the following with suitable examples:
Antiferromagnetism
Give reasons:Ferrimagnetic substances show better magnetism than antiferromagnetic substances.
The complexion [Ni(CN)4]2- is:
Explain why:
(i) Transition elements form coloured compounds.
(ii) Interhalogen compounds are more reactive than their constituent elements.
(iii) Cu+ is diamagnetic but Cu2+ is paramagnetic. (Z = 29)
Pyrolusite ore is _______.
Out of [CoF6]3- and [Co(en)3]3+, which one complex is
(i) paramagnetic
(ii) more stable
(iii) inner orbital complex and
(iv) high spin complex
(Atomic no. of Co = 27)
Give reason for the following :
Sulphur in vapour state shows paramagnetic behaviour.
The BH curve for a ferromagnetic material is shown in the figure. The material is placed inside a long solenoid which contains 1000 turns/cm. The current that should be passed in the solenonid to demagnetize the ferromagnet completely is
Compare dia, para and ferromagnetism.
Give the properties of dia/para/ferromagnetic materials.
What happens to the domains in a ferromagnetic material in the presence of external magnetic field?
Compare the properties of soft and hard ferromagnetic materials.
Substances which are weakly repelled in magnetic field are known as ____________.
All those atoms or molecules which have an odd number of electrons are
When heated to high temperature, ferromagnetic substance changes to ____________.
Assertion: On heating ferromagnetic or ferrimagnetic substances, they become paramagnetic.
Reason: The electrons change their spin on heating.
Fe3O4 (magnetite) is an example of ___________.
Which of the following arrangements shows schematic alignment of magnetic moments of antiferromagnetic substances?
The value of magnetic moment is zero in the case of antiferromagnetic substances because the domains:
(i) get oriented in the direction of the applied magnetic field.
(ii) get oriented opposite to the direction of the applied magnetic field.
(iii) are oppositely oriented with respect to each other without the application of magnetic field.
(iv) cancel out each other’s magnetic moment.
Which of the following statements are correct?
(i) Ferrimagnetic substances lose ferrimagnetism on heating and become paramagnetic.
(ii) Ferrimagnetic substances do not lose ferrimagnetism on heating and remain ferrimagnetic.
(iii) Antiferromagnetic substances have domain structures similar to ferromagnetic substances and their magnetic moments are not cancelled by each other.
(iv) In ferromagnetic substances all the domains get oriented in the direction of magnetic field and remain as such even after removing magnetic field.
Which one of the following pairs has only paramagnetic species?
Which one of the following homo-diatomic molecule is paramagnetic?
The heat of combustion of a substance is:
Which of the following is not a ferroelectric compound?
Magnetic materials used for making permanent magnets (P) and magnets in a transformer (T) have different properties of the following, which property best matches for the type of magnet required ?
The value of aluminium susceptibility is 2.2 × 10-5. The percentage increase in the magnetic field if space within a current carrying toroid is filled with aluminium is `"x"/10^4`. Then the value of x is ______.
Which one of the following compounds is diamagnetic and colourless?
The metal complex ion that is paramagnetic is ______.
(Atomic number of Fe = 26, Cu = 29, Co = 27 and Ni = 28)
