Statement I: Gold sol is prepared by Bredig's arc method. True. Bredig's arc method is indeed used for preparing metal sols like gold, platinum, and silver sols. In this method, an electric arc is struck between metal electrodes under water containing a stabilizer. Metal vapors formed are condensed to give colloidal particles (the sol). Statement II: Bredig's arc method involves only dispersion but not condensation. False. Bredig's arc method is actually a combination of dispersion and condensation methods: The metal is dispersed (broken up) by vaporization (dispersion). The vaporized metal atoms condense to form colloidal particles (condensation). Hence, both processes are involved. Correct answer: Option C Statement-I is correct, but Statement-II is not correct.
