When the equation ___Fe3O4 + ___Al ⟶ ___Al2O3 +___ Fe is correctly balance, what is the coefficient of Fe?

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)