Advertisements
Advertisements
Question
What is ferromagnetism?
Advertisements
Solution
- 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.
RELATED QUESTIONS
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.
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.
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 _______.
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
What is magnetic susceptibility?
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 that are strongly attracted by the applied magnetic field and can be permanently magnetized are ____________.
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.
Fe3O4 (magnetite) is an example of ___________.
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 ______.
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 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:
Some of the polar crystals when heated produces small electrical current. This phenomenon is called ______.
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 correct order of bond strength is ______.
Which of the following statements are correct?
- Electric monopoles do not exist whereas magnetic monopoles exist.
- Magnetic field lines due to a solenoid at its ends and outside cannot be completely straight and confined.
- Magnetic field lines are completely confined within a toroid.
- Magnetic field lines inside a bar magnet are not parallel.
- χ = -1 is the condition for a perfect diamagnetic material, where x is its magnetic susceptibility.
The susceptibility of a paramagnetic material is 99. The permeability of the material in Wb/A-m is ______.
[permeability of the free space μ0 = 4π × 10-7 Wb/A - m]
Among the following ions, which one has the highest paramagnetism?
Which of the following is not paramagnetic?
Which one of the following compounds is diamagnetic and colourless?
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)
