186. We took three weighings of trichlorosilane weighing 5.0000 g each. The first weighing was decomposed with HF and HCl, and after adding lumokupferon, 50 ml of a solution was obtained, the luminescence intensity of which was 55.0 c.u. From the second sample, as a result of appropriate processing, 10 ml of a solution was obtained, 5.0000 μg of copper, lumokupferon were added, and then diluted to 50 ml. The fluorescence intensity of this solution is 110 a.u. The third sample, containing no traces of copper, was treated in the same way as the first, and 50.0 ml of a solution was obtained, the fluorescence intensity of which turned out to be equivalent to the fluorescence intensity of 1.5000 μg of copper. Calculate the mass fraction of copper (%) in trichlorosilane.

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