Which statement about pH is correct?
At temperatures below 298 K298\text{ K}298 K, the pH of pure water is greater than 777.
The pH of a 0.50 mol dm−30.50\text{ mol dm}^{-3}0.50 mol dm−3 nitric acid solution is approximately −0.30-0.30−0.30.
The pH of 0.05 mol dm−30.05\text{ mol dm}^{-3}0.05 mol dm−3 sulfuric acid is greater than that of 0.05 mol dm−30.05\text{ mol dm}^{-3}0.05 mol dm−3 hydrochloric acid.
The pH of a weak acid is independent of temperature.
