Is CCl4 a lewis acid or a base?? WHY?

CCl₄ is neither a Lewis acid nor a Lewis base.

Lewis base donates electron pair toward the Lewis acid. CCl₄ molecule does not have lone pair of electrons, so that it is not a Lewis base. On the other hand, the central C atom of CCl₄ has completed the octet. As C atom cannot expand octet, it cannot accept electron pair, so that it is not a Lewis acid.

CCl4 neither accepts nor donates electrons, so it is neither a Lewis acid nor a Lewis base.

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