They are called Periods. Lesser known as series
By use IUPAC nomenclature rule compound N2O3 is named as
Dinitrogen trioxide ( answer d)
Nitrogen (N2) is named before oxygen(O3) since they are arranged alphabetically. In addition the prefix Di is used infront of nitrogen since they are two nitrogen atoms while prefix tri is used infront of oxide since they are 3 oxygen atoms
The gas is confined in 3.0 L container ( rigid container) ⇒ the volume remains constant when the temperature is increased from from 27oC to 77oC and therefore V1=V2 .
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