A compound of iron and chlorine is soluble in water .An excess of AgNO3 solution is added to precipitate the chloride ion as silver chloride, If a 134.8 mg of the compound gives 304.8 mg of AgCl , the oxidation state of iron in the compound

Open in App

Solution

Dear Student,

Let the compound be FeCl_x.
First, we find out the mass of chloride ions.
Now, molar mass of AgCl = 143.32 g/mol
Therefore , number of moles of AgCl = $\frac{304.8 \times 10^{- 3}}{143.32} = 0.0021$
Therefore, 0.0021 moles of Cl^-are present in AgCl.
Mass of Cl^-present in AgCl = 0.0021 x 35.453 = 74.45 mg

Now , Mass of FeCl₃ - Mass of Cl^- ions = Mass of Fe^+x
Mass of Fe^+x = 134.8 - 74.45 = 60.35 mg
Molar mass of Fe^+x = 55.85 g/mol
Number of moles of Fe^+x = $\frac{60.35}{55.85}$ = $0.00108 ≃ 0.001 m o l$
Since there is twice as much Cl^- as Fe^+x , the compound has the formula FeCl₂ and the oxidation state of Fe is +2.

Regards

Suggest Corrections

Similar questions

Q. A

999.6 mg

sample of a pure organic compound containing chlorine is fused with

N a_{2} O_{2}

to convert chlorine to

N a C l

. The sample is then dissolved in water, and the chloride precipitated with

A g N O_{3},

giving

1951.6 mg

A g C l

. If the molecular weight of organic compound is

147 u

, how many chlorine atoms does each molecule contain?

Q. When

A g N O_{3}

is added to a solution of

C o (N H_{3})_{5} C l_{3},

the precipitate of

A g C l

shows two ionisable chloride ions.

Q. When

A g N O_{3}

is added to a solution of

C o (N H_{3})_{5} C l_{3}

, the precipitate of

A g C l

shows two ionized chloride ions. This means:

An inorganic compound (A) is a strong reducing agent. Its hydrolysis in water gives a white turbidity (B). Aqueous solution of (A) gives a white precipitate (C) with NaOH solution which is soluble in excess of NaOH. (A) reduces auric chloride to produce purple of cassius. (A) also reduces iodine and gives chromyl chloride test. What is 'B' in the chemical reactions.

Q. An excess of AgNO3 is added to 100mL of a 0.01M solution of dichlorotetraaquachromium(III) chloride. The number of moles of AgCl precipitated would be ?

Join BYJU'S Learning Program