12. There is 100.0g samples of the following compounds: NH_3 , N_2O , HCN, N_2H_4 , and HNO_3 . Which sample has the least mass percent of nitrogen? (A) NH_3 (B) N_2O (C)HCN (D) HNO_3

19. For the equilibrium that exists in an aqueous solution of nitrous acid $(\mathrm{HNO}_2$ , a weak acid), the equilibrium constant expression is: (A) $K = \frac{[\mathrm{H}^{+}][\mathrm{NO}_{2}^{-}]}{[\mathrm{HNO}_{2}]}$ (B) $K = \frac{[\mathrm{H}^{+}][\mathrm{N}^{2+}][\mathrm{O}^{2-}]^2}{[\mathrm{HNO}_2]}$ (C) $K = [\mathrm{H}^{+}]\mathrm{[NO}_{2}^{-}]$ (D) $K = \frac{[\mathrm{H}^{+}]^{2}[\mathrm{NO}_{2}^{-}]}{[\mathrm{HNO}_{2}]}$

12. There is $100.0\mathrm{g}$ samples of the following compounds: $\mathrm{NH}_3$ , $\mathrm{N}_2\mathrm{O}$ , HCN, $\mathrm{N}_2\mathrm{H}_4$ , and $\mathrm{HNO}_3$ . Which sample has the least mass percent of nitrogen?
(A) $\mathrm{NH}_3$
(B) $\mathrm{N}_2\mathrm{O}$
(C)HCN
(D) $\mathrm{HNO}_3$

相關試題

相關試卷

12. There is $100.0\mathrm{g}$ samples of the following compounds: $\mathrm{NH}_3$ , $\mathrm{N}_2\mathrm{O}$ , HCN, $\mathrm{N}_2\mathrm{H}_4$ , and $\mathrm{HNO}_3$ . Which sample has the least mass percent of nitrogen?(A) $\mathrm{NH}_3$(B) $\mathrm{N}_2\mathrm{O}$(C)HCN(D) $\mathrm{HNO}_3$

相關試題

相關試卷

12. There is $100.0\mathrm{g}$ samples of the following compounds: $\mathrm{NH}_3$ , $\mathrm{N}_2\mathrm{O}$ , HCN, $\mathrm{N}_2\mathrm{H}_4$ , and $\mathrm{HNO}_3$ . Which sample has the least mass percent of nitrogen?
(A) $\mathrm{NH}_3$
(B) $\mathrm{N}_2\mathrm{O}$
(C)HCN
(D) $\mathrm{HNO}_3$