Advertisements
Advertisements
प्रश्न
Pyrolusite ore is _______.
विकल्प
MnO
MnO2
Mn2O7
Mn2O3
Advertisements
उत्तर
Pyrolusite ore is MnO2.
APPEARS IN
संबंधित प्रश्न
What is ferromagnetism?
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?
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.
Explain the following with suitable examples:
Paramagnetism
Explain the following with suitable examples:
Antiferromagnetism
Give reasons:Ferrimagnetic substances show better magnetism than antiferromagnetic substances.
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)
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.
What happens to the domains in a ferromagnetic material in the presence of external magnetic field?
Substances that are strongly attracted by the applied magnetic field and can be permanently magnetized are ____________.
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?
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+
Some of the polar crystals when heated produces small electrical current. This phenomenon is called ______.
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]
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 ______.
Among the following ions, which one has the highest paramagnetism?
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.
