Ionic Equilibrium Part 1

pH of an acidic solution should be less than 7 . The reason is that from H2O⋅[H+]=10−7M which cannot be neglected in comparison to 10−8M. The pH can be calculated as.
from acid, [H+]=10−8M.
from H2O,[H+]=10−7M
∴ Total [H+]=10−8+10−7
=10−8(1+10)=11×10−8
∴pH=−log[H+]
=−log‌11×10−8
=−[1.0414−8]=6.9586