Minimum pH balance is shown by aqueous solution of(1) 0.1M BaC{l_2} (2) 0.1M Ba{(N{O_3})_2} (3) 0.1M BeC{l_2} (4) 0.1M Ba{(OH)_2}

To determine which aqueous solution will have the lowest pH, we need to consider the ions that each compound will produce when dissolved in water.

0.1M BaCl2: This will dissociate into Ba^2+ and 2Cl^-. Neither of these ions will hydrolyze significantly in water, so the pH will not be significantly affected. Ba^2+ is a neutral ion.

0.1M Ba(NO3)2: This will dissociate into Ba^2+ and 2NO3^-. Similar to BaCl2, the Ba^2+ ion will not significantly hydrolyze, so the pH will not be significantly affected. NO3^- ions are neutral.

0.1M BeCl2: This will dissociate into Be^2+ and 2Cl^-. Be^2+ ions tend to form hydroxide ions in solution due to the reaction: Be^2+ + 2H2O → Be(OH)2 + 2H^+. This will make the solution acidic.

0.1M Ba(OH)2: This will dissociate into Ba^2+ and 2OH^-. The presence of OH^- ions will increase the pH of the solution, making it basic.

Therefore, the aqueous solution with the lowest pH will be option (3) 0.1M BeCl2.