Is c8h18 an electrolyte or non-electrolyte

C₈H₁₈ should be considered as the non-electrolyte.

The following information should be considered:

Electrolytes should be considered as substances so that it could be dissociated into ions at the time when it should be dissolved in the water. So this time the bonds should be needed. C₈H₁₈ should be the compound that has less electronegative that lies between the atoms so that the covalent compound could be made. On the other hand, electrons should be shared, non-polar, and very difficult for dissociate.  

Therefore we can conclude that C₈H₁₈ should be considered as the non-electrolyte.

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