Question

How do you calculate the Ka for the weak acid with pKa of 0.21.?

Answer 1

`K_a` `=` `10^(-0.21)` `=` `??`

Explanation:

The `p` function means to take the negative of the log to the base 10. The same for `pH`; here, if `pH` `=` `1`, then `[H^+]` `=` `10^-1` `mol*L^-1`. I recommend that you have a good look at your texts, and get this concept straight.

For instance when we write `log_ab = c`, we are saying that `a^c` `=` `b`. For practice, can you tell me what `log_(10)100`, and `log_(10)1000` are? Years ago, (20-30 years), before the advent of cheap electronic calculators, students used to be issued with log tables for multiplication and division.