# Question 12b01

Mar 22, 2015

The concentration of argon is $\text{66.7 ppm}$.

A concentration expressed in ppm, or parts per million, is defined as 1 miligram of solute in 1 kg, or 1,000 g, of solvent

$\text{1 mg"/"1 kg" = "1 ppm}$

Since you know that you get approximately 1 gram of argon for every 15 kg of air, all you have to do is convert this value into mg per kg to get the concentration in ppm

("1"cancel("g") "Ar")/"15 kg air" * "1000 mg"/("1"cancel("g")) = "66.7 mg Ar"/"1 kg of air" = "66.7 ppm"#