80-- $N_2$ and $O_2$ gases react completely with each other under suitable conditions. If the mass difference of the two gases at the start of the reaction is 0.125 grams, NO (as the only product of the reaction) is formed, and from this reaction the amount of NO gas formed --- with a sufficient amount of oxygen gas --- how many liters of $NO_2$ gas are formed at STP? $(N{=}14,\ O{=}16\ :\ \text{g.mol}^{-1})$ $2/8\ ,\ 3/75\ (1) \qquad\qquad 1/4\ ,\ 3/75\ (2) \qquad\qquad 7/8\ ,\ 1/875\ (3) \qquad\qquad 1/4\ ,\ 1/875\ (4)$
\textbf{80--} $N_2$ and $O_2$ gases react completely with each other under suitable conditions. If the mass difference of the two gases at the start of the reaction is \textbf{0.125 grams}, NO (as the only product of the reaction) is formed, and from this reaction the amount of NO gas formed --- with a sufficient amount of oxygen gas --- how many liters of $NO_2$ gas are formed at STP?
$(N{=}14,\ O{=}16\ :\ \text{g.mol}^{-1})$
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$2/8\ ,\ 3/75\ (1) \qquad\qquad 1/4\ ,\ 3/75\ (2) \qquad\qquad 7/8\ ,\ 1/875\ (3) \qquad\qquad 1/4\ ,\ 1/875\ (4)$
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