I cannot figure out how to write a formula question for the following:

1. -log(2.35 x 10-12)=    with -12 being an exponent.  The answer would be 11.63

The variable [x] could be the coefficient 2.35, the exponent, or the entire number.  The minimum and maximum variables are all very small numbers (way less than one).

2.  10(-x)  this is meant to be 10 raised to power of negative x.  X is the variable within the range of 0 and 14.

Can anyone help?