The real deal. Full pigment range, from left on the top most chart: Cad. Lemon, Cad. Yellow, Cad. Yellow Deep, Yellow Ochre Pale, Cad. Red, Terra Rosa, Alizarin, Trans. Oxide Red, Viridian, Cobalt Blue, Ultramarine Blue Deep. Things I missed out (or should've tried out): Cobalt Violet (in place of one of the warm yellows), Quinacridone Rose (instead of Alizarin), maybe branch out into oranges and darker blues like Prussian Blue or some Phthalo-containing blues and greens. This would push it closer towards a pallette approximating Sorolla's. Also, the red-oranges can be consolidated somewhat by using Burnt Sienna instead of the Red Oxide and Terra Rosa (but then again, I will lose the transparent quality of the Red Oxide).
In a way, doing these charts mean that you have to be very disciplined and rigorous with yourself. Clean everything and anything on the palette that could and would stain the mixtures, and always be sure what you are putting on to the chart squares at all times (that bluish green you see there? It's never going to be specific enough- just make sure that one batch leans towards blue, the other leans towards green, it has to be subtle but observable).
I guess the main lesson is to understand your palette of choice, and the nature of the pigments that you are using- here, student paints vs. artist quality (of differing brands) really shows in terms of the handling, tinting strength, and overall vibrancy. Some people will stumble across these same points through constant painting, which is entirely valid as well- the point is not to let these exercises dominate the fundamental skillsets of drawing and painting- they are means to an end, not something you do for 'Achievement Unlocked' street cred.
'Colour' is technically relative to the lighting situation and even on the support you are using, there will be different factors and permutations affecting the 'local colour'- it's the understanding of subtractive mixing, temperatures of pigments and their mixtures, that is the key to this specific type of exercise. You will encounter the legendary Cadmium Salute and the Viridian Handshake (just don't wear any new clothing in the studio, it'll end in tears), and there will be foul language employed. But at the end of the day, the understanding you'll get will be somewhat worth it. And it will be seen that these colour chart exercises are easy- compare them with, oh, the Munsell colour chip matching exercise. Now that's in a completely different league altogether.