100 ml of 0.5 M hydrazoic acid ( HN 3, K a =3.6 × 10-4) and 400 ml of 0.1 M cyanic acid ( HOCN , K a =. 8 × 10-4 ) are mixed. which of the following is (are) true for the final solution?

Question

100 ml of 0.5 M hydrazoic acid ( HN 3, K a =3.6 × 10-4) and 400 ml of 0.1 M cyanic acid ( HOCN , K a =. 8 × 10-4 ) are mixed. which of the following is (are) true for the final solution? (A) [ H +]=10-2 (B) [ N 3 -]=3.6 × 10-3 (C) [ OCN -]=4.571 × 10-3 (D) [ H +]=1.4 × 10-2

Tardigrade Admin · Accepted Answer

[ H +]=√ C 1 K a 1+ C 2 K a 2 =√10-1 × 3.6 × 10-4+8 × 10-2 × 8 × 10-4 =√3.6 × 10-5+6.4 × 10-5 =√10-4=10-2 M underset0.1HN 3 leftharpoons underset10-2H + + NH 3- so, [ N 3-]=3.6 × 10-2 × (10-1/10-2) =3.6 × 10-3 M [ OCN -]=8 × 10-4 × (8 × 10-2/10-2) =6.4 × 10-3 M

Q. $100 m l$ of $0.5 M$ hydrazoic acid $(H N_{3}, K_{a} = 3.6 \times 1 0^{- 4})$ and $400 m l$ of $0.1 M$ cyanic acid $(H OCN, K_{a} =$ $8 \times 1 0^{- 4}$ ) are mixed. which of the following is (are) true for the final solution?

$[H^{+}] = 1 0^{- 2}$

$[N_{3}^{-}] = 3.6 \times 1 0^{- 3}$

$[OC N^{-}] = 4.571 \times 1 0^{- 3}$

$[H^{+}] = 1.4 \times 1 0^{- 2}$

Q. 100ml of 0.5M hydrazoic acid (HN3​,Ka​=3.6×10−4) and 400ml of 0.1M cyanic acid (HOCN,Ka​= 8×10−4 ) are mixed. which of the following is (are) true for the final solution?

[H+]=10−2

[N3​−]=3.6×10−3

[OCN−]=4.571×10−3

[H+]=1.4×10−2

[H+]=C1​Ka1​​+C2​Ka2​​​ =10−1×3.6×10−4+8×10−2×8×10−4​ =3.6×10−5+6.4×10−5​ =10−4​=10−2M 0.1HN3​​⇌10−2H+​+NH3−​ so, [N3−​]=3.6×10−2×10−210−1​ =3.6×10−3M [OCN−]=8×10−4×10−28×10−2​ =6.4×10−3M

Q. $100 m l$ of $0.5 M$ hydrazoic acid $(H N_{3}, K_{a} = 3.6 \times 1 0^{- 4})$ and $400 m l$ of $0.1 M$ cyanic acid $(H OCN, K_{a} =$ $8 \times 1 0^{- 4}$ ) are mixed. which of the following is (are) true for the final solution?

$[H^{+}] = 1 0^{- 2}$

$[N_{3}^{-}] = 3.6 \times 1 0^{- 3}$

$[OC N^{-}] = 4.571 \times 1 0^{- 3}$

$[H^{+}] = 1.4 \times 1 0^{- 2}$