Question

Arrange these molecules in order of decreasing mass: C​6​H​14​ , NO​2​ , Fe​2​O​3 ​, and CaCO​

Answer 1

The following is the arrangement of the given molecules in decreasing order of mass: $\text{ Fe2O3} > \text{C6H14} > \text{CaCO} > \text{NO2}$

Solution:

First inorder to arrange the elements in descending order of their mass we have to calculate the molecular mass of each element. The calculation is as follows:

Mass of C6H14:

$C\rightarrow6\times12.01 = 72.06$

$H\rightarrow14\times1.008 = 14.112$

Mass of C6H14 is 86.172

Mass of NO2:

$N\rightarrow1\times14.0067 = 14.0067$

$O\rightarrow2\times15.9994 = 31.9988$

Mass of NO2 is 46.0055

Mass of Fe​2​O3:

$Fe\rightarrow2\times55.845 = 111.69$

$O\rightarrow3\times15.9994 = 47.9982$

Mass of Fe2O3 is 159.6882

Mass of CaCO:

$Ca\rightarrow1\times40.078 = 40.078$

$C\rightarrow1\times12.01 = 12.01$

$O\rightarrow1\times15.9994 = 15.9994$

Mass of CaCO will be 68.0874

So, the order will be $159.6882>86.172>68.0874>46.0055$ which is $\text{ Fe2O3} > \text{C6H14} > \text{CaCO} > \text{NO2}$