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The equilibrium constant for the reaction $ SO_{3(g)} \rightleftharpoons SO_{2(g)} + 1/2 O_{2(g)} Kc = 4.9 \times 10 ^ {-2} $ The value for the $K_C$ of the reaction $2SO_{2(g)} + O_{2(g)} \rightleftharpoons 2SO_{3(g)} $ will be

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Explanation

Equilibrium constant for the reaction $ SO_{ 2 (g) } + { 1 \over 2 } O_{ 2 (g) } \rightleftharpoons SO_{3(g)} $ and for reaction $ 2 SO_{ 2(g)} + O_{2(g)} \rightleftharpoons 2SO_{3(g)} $ $ K_C = ( { 1 \over 4.9 \times 10 ^ {-2} } ) ^ 2 = 416 .49 $

$ P^H$ of 0.1 M solution of weak acid is 3. The value of ionisation constant Ka of acid is

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Explanation

$ P^H = 3 \therefore [ H^+_3 ] = 1 \times 10 ^ {-3} $ $ Ka = { [ H_3 ^ + O ] ^2 \over C } = { ( 1 \times 10 ^ {-3} ) ^2 \over 0.1 } = 1 \times 10 ^ {-5} $

Three reactions involving $ H_2 PO^- _ 4 $ are given below.

(i) $ H_3 PO_4 + H_2O \rightleftharpoons H_3 O^+ + H_2 PO^- _4 $ (ii) $ H_2 PO^- _4 + H_2 O \rightleftharpoons HPO^{-2} _4 + H^+ _3 O$
(iii) $ H_2 PO^- _4 + OH^- \rightleftharpoons H_3 PO_4 + O^{2-} $ In which of the above does $H_2PO^- _ 4 $ act as an acid.

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Explanation

According to lowry-bronsted acid base theory in (ii) reaction $ H_2 PO_4 ^- donates H^+ ion to H_2 O$ it acts as an acid.

For the reaction $ 2 NO_{2(g)} \rightleftharpoons 2 NO_{(g)} + O_{2(g)} Kc = 1.8 \times 10 ^ {-6} at 184 ^\circ c R = 0.0831 KJ/mol.K $ When $ K_P and K_C are compared at 184 ^\circ C $ it is found that :

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Explanation

$ K_p = Kc ( RT) ^ { \triangle n (g) } \triangle n (g) = 1 $ $ = Kc \times 0.0831 \times 457 it means Kp \gt Kc $

Water is a

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Explanation

Water is an amphiprotic solvent as it can accept protons as well as give protons.

Ammonium ion is

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Explanation

Ammonium ion $ (NH _4 ^ +) is a conjugate acid of NH_3 $ $ NH_3 + H_2O \rightleftharpoons NH_4 ^ + + OH ^ - $ Bronsted base Conjugate acid

Species acting both as bronsted acid and a base is

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Explanation

$ HSO_4 ^ - $ can act as a bronsted acid as well as bronsted base. $ HSO_4 ^ - + H_2 O \rightleftharpoons SO_4 ^ {2-} + H_3 ^ + O $ Acid $ HSO_4 ^ - + H_2 O \rightleftharpoons H_2 SO_4 + OH^ - $ Base

A solution ofan acid has $ P^H = 4.70 find out the concentration of OH ^- pK_w =14 $

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Explanation

$ P ^ H = 4.7 \therefore [ H_3 ^ + O ] = 1.995 \times 10 ^ {-5} pK_w = 14 \therefore K_w = 1 \times 10 ^ {-14} $ $ = - log [ H_3 ^ + O ] Now K_w = [ H_3 ^ + O ] [ OH^- ] $ $ \therefore [OH^-] = { 1 \times 10 ^ { -14} \over 1.995 \times 10 ^ {-5} } = 5 \times 10 ^ {-10} M $

The conjugate base of $ H_2PO^- _4 $ is

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Explanation

Conjugate base of $ H_2 PO_4 ^ - is HPO_4 ^ {2-} $ $ H_2 PO_4 ^ - + H_2 O \rightleftharpoons HPO_4 ^ {2-} + H_3 O ^ + $ Acid

What is the conjugate base of $OH ^ - $ ?

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Explanation

Conjugate base of $ OH^- $ $ OH^- + H_2 O \rightleftharpoons O ^ {2-} + H_3 O ^ + $

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