The incorrect statement among the following is :
Solution
Red colour of ruby is due to presence of ${Cr}^{3+} $ (chromium ions), not ${Co}^{3+} $ (cobalt ions). in Al<sub>2</sub>O<sub>3</sub>.
Chromium is the trace element that causes ruby’s red colour, which
ranges from an orange red to a publish red. The strength of ruby’s
red depends on how much chromium is present.
About this question
Subject: Chemistry · Chapter: d and f Block Elements · Topic: Properties of Transition Metals
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