Answer
Lime juice is more acidic.
Work Step by Step
- The more acidic solution will be the one with the higher hydronium concentration:
- Carbonated beverage:
$[H_3O^+] = 10^{-pH}$
$[H_3O^+] = 10^{- 2.10}$
$[H_3O^+] = 7.9 \times 10^{- 3}M$
- Lime juice:
$[H_3O^+] = 1.3 \times 10^{-2}M$
Since $1.3 \times 10^{-2}M > 7.9 \times 10^{-3}M$, the lime juice is more acidic.
