Exhibit 16-1 Consider the Equilibrium Reaction Below to Answer the Following

Multiple Choice

Exhibit 16-1 Consider the equilibrium reaction below to answer the following question(s) . HNO₂ + H₂ O H₃O + + NO₂ 1 - K a (HNO₂ ) = 4.5 10 - 4
-Refer to Exhibit 16-1. What is the concentration of nitrite ion, NO₂ - , present at equilibrium if 0.100 moles of HCl are added to 0.200 moles of HNO₂ to form one-liter of solution?

A) [NO₂ ^- ] = 9.00×10 ^{- 4} M
B) [NO₂ ^- ] = 2.12×10 ^{- 3} M
C) [NO₂ ^- ] = 9.49×10 ^{- 3} M
D) [NO₂ ^- ] = 0.100 M
E) [NO₂ ^- ] = 0.200 M