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What is ferrous ammonium sulfate used for

Author

William Harris

Updated on March 30, 2026

Ferrous Ammonium Sulfate is a pale green or blue-green powder or sand-like solid. It is used in photography, analytical chemistry, and Iron-plating baths.

What is other name of ferrous ammonium sulphate?

NamesIUPAC name Ammonium iron(II) sulfateOther names Ferrous ammonium sulfate Ammonium iron sulfate Mohr’s saltIdentifiersCAS Numberanhydrous: 10045-89-3 hexahydrate: 7783-85-9

What happens if you drink Mohr salt?

SOLID Irritating to skin and eyes. If swallowed will cause nausea and vomiting. … IF IN EYES, hold eyelids open and flush with plenty of water. IF SWALLOWED and victim is CONSCIOUS, have victim drink water or milk and have victim induce vomiting.

What is the difference between Ferrous ammonium sulphate and ammonium ferrous sulphate?

Ferrous ammonium sulfate is a pale green crystalline compound which does not effloresce like ferrous sulfate. It is less readily oxidised than FeSO4 and therefore, a better volumetric reagent in preference to ferrous sulfate.

Is ammonium sulfate safe to use?

Ammonium sulfate is potentially dangerous to both people and the environment, so it requires care in its use. It can cause severe irritation and inflammation of the respiratory tract if inhaled.

Why is FAS called Mohr's salt?

It derives its name from the German chemist Karl Friedrich Mohr, a 19th century pioneer in the development of titration methodology. Mohr’s salt is used in analytical chemistry as the preferred source of ferrous ions due to the solid’s extended shelf life and resistance to oxidation.

Is ferrous ammonium sulphate a double salt?

Mohr’s salt is an inorganic compound which is a double salt with the formula (NH4)2Fe(SO4)2(H2O)6. It is a common laboratory reagent with IUPAC name ammonium iron(II) sulfate.

What is ammonium sulfate?

Ammonium sulfate is an inorganic sulfate salt obtained by reaction of sulfuric acid with two equivalents of ammonia. A high-melting (decomposes above 280℃) white solid which is very soluble in water (70.6 g/100 g water at 0℃; 103.8 g/100 g water at 100℃), it is widely used as a fertilizer for alkaline soils.

What weight of ferrous ammonium sulphate is needed?

In standard form, normality is the number of grams or mole equivalents of solute present in one litre of a solution. $ 3.92 $ grams of ferrous ammonium sulphate is needed to prepare $ 100 ml $ of $ 0.1 $ normal solution. Therefore the correct answer is option B.

How do you make FAS solution?

Ferrous Ammonium Sulphate Solution Preparation Dissolve 40 g of ferrous ammonium sulfate in a previously cooled mixture of 40 ml of sulphuric acid and 200 ml of water. Dilute with sufficient freshly boiled and cooled water to produce 1000 ml.

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How do you make double salt of ferrous ammonium sulphate?

To prepare double salts: ferrous ammonium sulphate (Mohr’s salt) and potash alum. Fe2+ and Al3+ ions undergo hydrolysis, therefore, while preparing aqueous solutions of ferrous sulphate and aluminium sulphate in water, 2-3 mL dilute sulphuric acid is added to prevent the hydrolysis of these salts.

How do you store Ferrous ammonium sulfate?

* Store in tightly closed containers in a cool, well-ventilated area away from LIGHT and AIR. * Immediately flush with large amounts of water for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention.

Is Ferrous ammonium sulfate a reducing agent?

Ferrous ammonium sulphate is a double salt known as Mohr’s salt. In this titration, potassium permanganate acts as an oxidizing agent and Mohr’s salt acts as a reducing agent. … In this redox reaction, ferrous ions from Mohr’s salt get oxidised.

What plants benefit from ammonium sulfate?

A: Ammonium sulfate is nitrogen and as such, has a big place in virtually all gardening we do. Grass, trees, shrubs, flowers, vines, vegetables and so on all use nitrogen.

How do you use ammonium sulfate?

Apply ammonium sulfate in 45- to 60-day intervals. You can spread granules of ammonium sulfate with a drop or broadcast spreader. If using liquid spray ammonium sulfate, dissolve up to 3 tablespoons of fertilizer per gallon of water. Use it to water the plants deficient in nitrogen and sulfur.

Is ammonium sulfate good for tomatoes?

1. Is Ammonium Sulfate fertilizer good for tomato plants? … Tomato Fertilizer for tomato plants since that was specifically formulated for maximum yield for tomato plants. However, if you are using dry granular fertilizer then you should apply Ammonium Sulfate at the rate of 1 tablespoon per plant.

What is meaning of double salt?

A double salt is a salt that contains more than one different cation or anion. … When dissolved in water, a double salt acts as a mixture of the two separate salts: it completely dissociates into simple ions while a hexaaquo complex does not; the complex ion remains unchanged.

How do you prepare ammonium sulfate?

Preparation. Ammonium sulfate is made by treating ammonia with sulfuric acid: 2 NH3 + H2SO4 → (NH4)2SO. A mixture of ammonia gas and water vapor is introduced into a reactor that contains a saturated solution of ammonium sulfate and about 2 to 4% of free sulfuric acid at 60 °C.

What is the equivalent weight of FAS?

-Hence, the equivalent weight of ferrous ammonium sulphate is 392.13g/mol.

Why is H2SO4 added in FAS solution?

The reason why you add sulfuric acid before water is that the oxidation of the ferrous ion by dissolved oxygen in water is fast at neutral to high pH. You can see this yourself by dissolving FAS in water with no acid added and watching the solution turn a cloudy orange, indicating the formation of ferric ions.

Why Mohr's salt is used instead of ferrous sulphate?

Mohr’s salt is a better volumetric agent then ferrous sulphate because. All the chemical reactions given by ferrous sulphate are given by Mohr’s salt. It does not effloresce like ferrous sulphate. It is less readily oxidised in the solid state.

What is the Colour of Mohr's salt?

At STP, Mohr’s salt exists as a crystalline solid that is bluish-green in colour.

How do you determine the strength of Ferrous ammonium sulphate?

Object: To determine the strength (in g/L) of ferrous ammonium sulphate (FeSO4, (NH4)2SO4,6H2O) by titrating it against standard (1.0 g/L ) potassium dichromate (K2Cr2O7) solution. Principle: Ferrous ammonium sulphate [FeSO4, (NH4)2SO4,6H2O] is a stable double salt with FeSO4 being its active constituent.

Is Ferrous ammonium sulfate a salt?

Ferrous ammonium sulfate appears as a light green crystalline solid. … It is a metal sulfate, an iron molecular entity and an ammonium salt.

Is Ferrous ammonium sulphate a primary standard?

Known as Mohr’s salt, ferrous ammonium sulfate is used as a primary standard in quantitative analysis. It is also used in photographic solutions and in Dosimeter badges.

What is ammonia used for?

How is ammonia used? About 80% of the ammonia produced by industry is used in agriculture as fertilizer. Ammonia is also used as a refrigerant gas, for purification of water supplies, and in the manufacture of plastics, explosives, textiles, pesticides, dyes and other chemicals.

How do you standardize a FAS solution?

The ferrous ammonium sulfate (FAS) titrant must be standardized daily by the following procedure: Dilute 10ml of standard potassium dichromate (K2Cr2O7) solution to 100ml with distilled water. Slowly add 30ml of concentrated sulphuric acid and cool to room temperature.

How do you standardize ferrous sulfate?

Standardization of ferrous sulphate solution: 10 ml of the normal potassium dichromate solution will be run from a burette into a 500 il conical flask. 20 ml concentrated sulphuric acid shall then be added carefully and the mixture swirled and allowed to cool for some minutes.

How do you make ferrous sulfate?

can be prepared by adding slight excess of iron to dilute sulphuric acid. Fe + H2SO4 FeSO4 + H2 After completion of reaction the liquid is concentrated by boiling. Then the solution is filtered and allowed to cool. The crystals are separated and dried, then recrystalizes from water.

Why are crystals of Mohr's salt washed with alcohol?

Wash the crystals in the china-dish with a small quantity of alcohol to remove any sulphuric acid sticking to the crystals. Dry the crystals by placing them between filter paper pads.

Is potash alum double salt?

Potash alum is a chemical compound widely used as the potassium sulfate dodecahydrate. It is double salt that is used commonly in medicine and the water treatment process.