There are two kinds of logarithms that chemists use:

1. log to the base 10, log:

   log₁₀ (100) = 2 is equivalent to 10² = 100

   Calculator keystrokes:
   1. Press 'log' key.
   2. Press '100' on number pad.
   3. Screen display should read 2.

2. natural log, ln:

   ln (30) = log_e (30) = 3.401197382 is equivalent to e³⁰ = 2.71828182845904523536028747135266249775724709369995...^3.401197382 = 30

   Calculator keystrokes:
   1. Press 'ln' key.
   2. Press '30' on number pad.
   3. Screen display should read 3.401197382.

Convert between log to the base 10 (log) and natural log (ln)

The conversion between log to the base 10 (log) and natural log (ln) is

<math>ln (y) = 2.303 * log (y)</math>

or

<math>log (y) = \frac{1}{2.303} * ln (y)</math>

Logarithm