Question

Three identical flasks contain three different gases at standard temperature and pressure. Flask A contains CH4, flask B contains CO2, flask C contains N2. Which flask contains the largest number of molecules?

Answer 1

Answer:

FLASK B WHICH CONTAINS CO2 HAS THE HIGHEST NUMBER OF MOLECULES AS IT CONTAINS THE HIGHEST MOLECULAR MASS OF 44 G/MOL.

Explanation:

Flask A contains CH4

Flask B contaims CO2

Flask C contains N2

To know the flask containing the largest number of molecules, we find the molar mass of the molecules in the flask and the largest is the one with the highest number of the relative molecular mass.

Molecular Mass of CH4 (C = 12, H =1) = ( 12 + 1*4) g/mol

= 16 g/mol

Molecular mass of CO2 (C= 12, 0= 16) = (12 + 16*2) g/mol

= 12 + 32 g/mol

= 44 g/mol

Molecular mass of N2 (N=14) = 14 * 2 g/mol

= 28 g/mol

Hence, the flask with the largest number of molecules is the flask with the highest relative molecular mass. The highest molecular mass is 44 g/mol and it is for the gas CO2 in Flask B.

So therefore, Flask B has the highest number of molecules in it.