What is the ph of an aqueous solution at 25.0 °c that contains 3.98 ⋅ 10-9 m hydronium ion? what is the ph of an aqueous solution at 25.0 °c that contains 3.98 10-9 m hydronium ion? 5.600 9.000 8.400 7.000 3.980?

Which of the following natural processes is most likely to support the formation of an underwater sinkhole? a pollution buildup from deposited minerals b limestone cave collapsing due to changes in sea level c erosion of large amounts of sand moved by ocean waves d oxidation of rock formed by chemical weathering