Explain the following Observation Fe(OH)3 SOL COAGULATES ON ADDITION OF A SOLUTION OF K2 SO4

When an electrolyte is added to the sol, the colloidal particles take up ions carrying opposite charges from the electrolyte. As a result, their charge gets neutralised and this causes the uncharged particles to come closer and to get coagulated. Here Fe³⁺ ions of ferric hydroxide are attracted by the negatively charged SO₄^2- sol particles and their charge gets neutralised. This leads to coagulation.