The second one. Subscripts are always related to molecules, not atoms and only count the number of molecules of a single element unless in a form such as (CO3)2. In this case, there are 2 molecules of carbonate and 6 of oxygen
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Answer:
Because their Molar masses or their densities are almost the same.
Explanation:
Average molecular mass of the air is 28.97 g/mol.
Molar mass of nitrogen gas (N2) ≈ 2*14.01 = 28.02 g/mol
As we can see that these molar masses is to close.
To collect gas over the air, the gas should be very light, that means that its molar mass should be much less than molar mass of the air.
This is what the lewis structure looks like
so Each carbon atom has 4 unpaired electrons available for bonding.
Each of the 3 chlorine atoms has a single unpaired electron available for bonding.
The hydrogen has a single electron available for bonding.
This results in carbon forming 4 single covalent bonds.
The systematic name is trichloromethane.