Which set of ions exhibit specific colours? (atomic number of sc = 21, ti = 22, v=23, mn = 25, fe = 26, ni = 28 cu = 29 and zn =30).

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

Classify this reaction: 2al+n2-> aln.

At element makes up all organic compounds?