About primary cells batteries

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Primary cells: 

In these cells, the chemicals used up during the supply of electrical energy cannot be regenerated by passing current into the used up cell from external source. In other words, the cell reaction is not reversible. It is, therefore, after sometimes, the battery becomes dead. Such primary cells are called dry cells. The dry cells are used in torches, radio receivers, electronic calculators, hearing aids, etc.

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Siemens Ozoniser how Siemens Ozoniser work

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Rutile structure

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Paramagnetic substances

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