Why does the electronegativity change as you move down a group?

Going down a group, the electronegativity of atoms decreases. As you move down a group in the periodic table, atoms increase in size, with a greater number of energy levels. The extra energy levels and increased covalent radius keep the bonding electrons further away from the nucleus.

Explanation:

Gelatin would be a homogeneous mixture.

Explanation:
Gelatin includes collagen from the proteins and peptides of animal tissues. When mixed together, you cannot see these items separately and therefore make a uniform substance.
PS: This mixture is caused by hydrolysis
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