Page 1 of 1

SigFig: 12.59

Posted: Sat Jan 19, 2019 8:21 am
by Douglas Nguyen 2J
The initial values given for the question were 0.0073 M of codeine and pKa of conjugate acid was 8.21. With that, I assumed there were 2 significant figures (0.0073).

The answer was: 1.5%, 3.96, 10.04
For 10.04, does ".04" count as two significant figures since it's after the decimal point? Or should it be 10.037 (this was the calculation I got), not counting the zero?

Re: SigFig: 12.59

Posted: Sat Jan 19, 2019 9:45 am
by klarratt2
If 10.04 is a pH/pKa value, then it has 2 sig figs. For pH/pKa/pKb, sig figs are counted as the amount of numbers past the decimal. So 10.04 would be 2 sig figs and 10.037 would be 3 (you count the zero because it is between two nonzero numbers).