Answer:
Step-by-step explanation:
Multiply the decimal by 100 and write the result with the percentage sign: 0.75 × 100 = 75%.
The hydronium ion is H₃O⁺ and its concentration is equivalent to the H⁺ ion concentration. The H⁺ ion concentration is given by:
pH = -log[H⁺]
[H⁺] = 10^(-8.2)
[H⁺] = 6.31 x 10⁻⁹ mole/dm³
The hydronium ion concentration is 6.31 x 10⁻⁹ mole/dm³
25% of something is 5000000, so total is 4*5000000 = 20 million
