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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.
संबंधित प्रश्न
Iron (z=26) is highly ferromagnetic. Explain.
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:
Paramagnetism
Explain the following with suitable examples:
Antiferromagnetism
Give reasons:Ferrimagnetic substances show better magnetism than antiferromagnetic substances.
The complexion [Ni(CN)4]2- is:
Pyrolusite ore is _______.
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.
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
Substances that are strongly attracted by the applied magnetic field and can be permanently magnetized are ____________.
When heated to high temperature, ferromagnetic substance changes to ____________.
Fe3O4 is ____________.
Which type of substances would make better permanent magnets?
Assertion: On heating ferromagnetic or ferrimagnetic substances, they become paramagnetic.
Reason: The electrons change their spin on heating.
Which of the following arrangements shows schematic alignment of magnetic moments of antiferromagnetic substances?
Which of the following statements is not true?
A ferromagnetic substance becomes a permanent magnet when it is placed in a magnetic field becuase ______.
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 would feel attraction when placed in magnetic field: Co2+, Ag+, Ti4+, Zn2+
Which one of the following pairs has only paramagnetic species?
Some of the polar crystals when heated produces small electrical current. This phenomenon is called ______.
Given below are two statements labelled as Assertion (A) and Reason (R).
Assertion: Magnetic moment values of actinides are lesser than the theoretically predicted values.
Reason: Actinide elements are strongly paramagnetic.
Select the most appropriate answer from the options given below:
Among the following ions, which one has the highest paramagnetism?
Match items of List - I with those of List - II:
| List - I | List - II | ||
| (Property) | (Example) | ||
| (A) | Diamagnetism | (i) | MnO |
| (B) | Ferrimagnetism | (ii) | O2 |
| (C) | Paramagnetism | (iii) | NaCl |
| (D) | Antiferromagnetism | (iv) | Fe3O4 |
Choose the most appropriate answer from the options given below:
Give a reason for the following:
Cu+2 salts are paramagnetic, while Cu+ salts are diamagnetic.
The metal complex ion that is paramagnetic is ______.
(Atomic number of Fe = 26, Cu = 29, Co = 27 and Ni = 28)
The calculated spin only magnetic moment of Cr2+ ion is ______.
