Explanation:
It is known that for [tex]NO_{2}[/tex], ppm present in 1 [tex]mg/m^{3}[/tex] are as follows.
1 [tex]\frac{mg}{m^{3}}[/tex] = 0.494 ppm
So, 150 [tex]pg/m^{3}[/tex] = [tex]\frac{150}{1000} mg/m^{3}[/tex]
= 0.15 [tex]mg/m^{3}[/tex]
Therefore, calculate the equivalent concentration in ppm as follows.
[tex]0.15 \times 0.494 ppm[/tex]
= 0.074 ppm
Thus, we can conclude that the equivalent concentration in ppm at STP is 0.074 ppm.
