The concentration of a pollutant is 0.5 ppb. What is its concentration in ng/m³?
Q1. The concentration of a pollutant is 0.5 ppb. What is its concentration in ng/m³?
Answer: 5 ng/m³
Explanation: 1 ppb = 1 ng/L for gases or 1 μg/m³; assuming standard conditions, 0.5 ppb = 0.5 μg/m³ or 500 ng/m³, but for air, 1 ppb = 1 ng/L = 1 μg/m³ at STP, for an ideal gas.