What is the pH in 8 M of NaOH
McCann always gives good answers and contriburtes a lot to this site, but this time he is wrong. The PH scale is from 0 to 14 (in extreme, very rare cases the PH can be below 0). PH =7 is neutral, the lower it is (below 7) the more acid it is and the more it is above 7 the more alkline it is. PH of 14.9 does not exist.
You are wrong and pH can be above 14.
Also, below 0 is not uncommon nor rare and many concentrated acids are such as that, below 0.