MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Multiple Bond Formation

Cd 2+ and C...

Question

${C d}^{2 +}$ and ${C u}^{2 +}$ are separated by complex formation using $K C N$ in which $K_{3} [{C u (C N)}_{4}]$ is more stable than $K_{4} [{C d (C N)}_{4}]$ ; on passing $H_{2} S$ gas $C d S$ is percipitated.

If the given statement is true enter 1, else enter 0.

Open in App

Solution

${C d}^{2 +}$ and ${C u}^{2 +}$ are separated by complex formation formation using $K C N$ in which. $K_{3} [{C u (C N)}_{4}]$ . is more stable than . $K_{4} [{C d (C N)}_{4}]$ ; on passing $H_{2} S$ gas. $C d S$ is percipitated.
$[C u (N H_{3})]_{4} S O_{4} + 10 K C N + 8 H_{2} O \to 2 K_{3} [C u (C N)_{4}] + 2 K_{2} S O_{4} + 8 N H_{4} O H + (C N)_{2}$
$[C d (N H_{3})]_{4} S O_{4} + 4 K C N + 4 H_{2} O \to K_{2} [C d (C N)_{4}] + K_{2} S O_{4} + 4 N H_{4} O H$
The second ionization of potassium cadmicyanide is higher than that of potassium cuprocyanide so that suffiient Cd (II) ions are present in solution. Hence, when hydrogen sulphide is passed, only CdS is precipitated.

Suggest Corrections

thumbs-up

0

Similar questions

C u^{2 +}

C d^{2 +}

both are present, it is difficult to analyse. A scheme to analyse in a mixture is given below.
KCN forms complex with

C u^{2 +}

C d^{2 +}

C u^{2 +} + 2 C N^{-} ⟶ C u (C N)_{2}

C u (C N)_{2} ⟶ 2 C u C N ↓ + (C N)_{2}

C u C N + 3 K C N K_{3} C u (C N)_{4}] s t a b l e C d^{2 +} + K C N ⟶ K_{2} [C d (C N)_{4}] u n s t a b l e

H_{2} S

gas is passed, unstable complex of

C d^{2 +}

gives yellow ppt

[C d (C N)_{4}]^{2 -} ⇌ C d^{2 +} + 4 C N^{-}

C d^{2 +} + S^{2 -} ⟶ C d S y e l l o w ↓

If true enter 1, else enter 0.

{C u}^{2 +}

{C d}^{2 +}

solution is complexed by addition of

K C N S

. Reason: On passing

H_{2} S

gas stable complex

[{C u (C N)}_{4}]^{3 -}

is not affected.

Read the above assertion and reason and choose the corret option regarding it.

Q. Precipitation of

{C d}^{2 +}

{C u}^{2 +}

takes place in presence of dil.

H C l

H_{2} S

If the given statement is true enter 1, else enter 0.

Q. A reagent that can detect any of

{C u}^{2 +}, {F e}^{3 +}, {Z n}^{2 +}

{C d}^{2 +}

K_{4} [{F e (C N)}_{6}]

If the given statement is true enter 1 else enter 0.

K C N

(excess) is added to a

C u^{2 +}

, final species formed is

[C u (C N)_{4}]^{3 -}

If true enter 1, else enter 0.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Multiple Bond Formation

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Multiple Bond Formation

Standard XII Chemistry

Join BYJU'S Learning Program

CrossIcon