Explain how mendal experiments with seed colors disapproved the common belief of blending inheritance

The theory of blending inheritance was used to describe an actual blending of our alleles, that together would form a new allele. For example, skin color and height would be the result of the blend of the parent's alleles.

This theory doesn't explain why some traits disapear or are discrete.

On the other hand, Mendel's experiments with seed colors explains it. He demonstrated that genes are inherited in pairs and that in hybrid organisms, dominant versions of that gene, could hide the presence of a recessive version of that same gene.