Question

use the references to access important values if needed for this question.
arrange the following elements and/or compounds in order of increasing average molecular speed. all are at the same temperature.
ammonia, argon, sulfur dioxide, neon
1 (slowest) 2 3 4 (fastest)
____ < __ < __ < ____
drag and drop your selection from the following list to complete the answer:
ne nh₃ so₂ ar

Explanation:

Step1: Calculate molar masses

Molar mass of \(NH_3\): \(M_{NH_3}=14 + 3\times1=17\space g/mol\)
Molar mass of \(Ar\): \(M_{Ar}=40\space g/mol\)
Molar mass of \(SO_2\): \(M_{SO_2}=32+2\times16 = 64\space g/mol\)
Molar mass of \(Ne\): \(M_{Ne}=20\space g/mol\)

Step2: Use the formula for average molecular speed

The formula for the average molecular speed \(\bar{v}=\sqrt{\frac{8RT}{\pi M}}\), where \(R\) is the gas constant, \(T\) is the temperature and \(M\) is the molar mass. At the same temperature (\(T\) is constant), \(\bar{v}\propto\frac{1}{\sqrt{M}}\) (inverse - proportional to the square root of the molar mass).

Step3: Compare molar masses

Since \(M_{SO_2}(64\space g/mol)>M_{Ar}(40\space g/mol)>M_{Ne}(20\space g/mol)>M_{NH_3}(17\space g/mol)\)

Answer:

\(SO_2