when an alkali metal dissolves in liquid ammonia, the solution can acquire different colors. Explain .

when an alkali metal dissolves in liquid ammonia, the solution can acquire different colors. Explain .
by

1 Answer

Answer :

Ans. The dilute solutions of alkali metals in liquid ammonia exhibit dark blue color because ammoniated electrons absorb energy corresponding the red region of the visible light. However, If the concentration increases above 3M, the color changes to copper-bronze and the solution acquires metallic luster due to the formation of metal ion clusters.
by

Related questions

Sodium dissolves in liquid ammonia to form a solution which shows electrical conductivity.

Description : Sodium dissolves in liquid ammonia to form a solution which shows electrical conductivity.

Last Answer : Explain : Sodium dissolves in liquid ammonia to form a solution which shows electrical conductivity.

AgCl dissolves in ammonia solution giving

Description : AgCl dissolves in ammonia solution giving

Last Answer : AgCl dissolves in ammonia solution giving A. `Ag^(+), NH_(4)^(+) " and" Cl^(-)` B. `[Ag(NH_(3))]^(+) " and ... D. `[Ag(NH_(3))_(2)]^(+) " and" Cl^(-)`

A metal salt solution gives a yellow precipitate with silver nitrate. The precipitate dissolves in dilute nitric acid as well as in ammonium hydroxide

Description : A metal salt solution gives a yellow precipitate with silver nitrate. The precipitate dissolves in dilute nitric acid as well as in ammonium hydroxide

Last Answer : A metal salt solution gives a yellow precipitate with silver nitrate. The precipitate dissolves in dilute nitric acid as ... (3-)` D. `SO_(4)^(2-)`

What is the name of the process where a substance dissolves in a liquid to form a solution?

Description : What is the name of the process where a substance dissolves in a liquid to form a solution?

Last Answer : A: Dissolution.

The rate of solid-liquid extraction is limited by the (A) Phase change of the solute as it dissolves in the solvent (B) Diffusion of the solute through the solvent in the pores to the outside of the particle (C) Diffusion of the solute from the solution in contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'

Description : The rate of solid-liquid extraction is limited by the (A) Phase change of the solute as it dissolves in the solvent (B) Diffusion of the solute through the solvent in the pores to the outside of the particle (C) ... contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'

Last Answer : (D) All 'a', 'b' & 'c'

0.257g of organic substance was heated with conc. sulphuric acid and then distilled with excess of strong alkali .the ammonia gas evolved was absorbed in 50ml of .1M HCl which required 23.2ml of c for neutralization at the end of the process. Determine the % of nitrogen in the compound ?

Description : 0.257g of organic substance was heated with conc. sulphuric acid and then distilled with excess of strong alkali .the ammonia gas evolved was absorbed in 50ml of .1M HCl which required 23.2ml of c for neutralization at the end of the process. Determine the % of nitrogen in the compound ?

Last Answer : A. Vol of 0 .1M HCl taken = 50ml Vol of .1MNaOH used for neutralization of unused acid=23.2ml Now, 23.2 ml of .1MNaOH =23.2ml of .1MHCl Vol of .1MHCl unused=23.2ml Vol of .1MHCl required ... NH3 solution contain nitrogen = 14*26.8/10*1000 Percentage of Nitrogen=14*26.8*100/10*1000*.257 =14.6%

What will be formed when a metal oxide dissolves in water?

Description : What will be formed when a metal oxide dissolves in water?

Last Answer : ANSWER: A BASE

A Solution of sodium in liquid ammonia is strongly reducing in nature.Why?

Description : A Solution of sodium in liquid ammonia is strongly reducing in nature.Why?

Last Answer : Ans Due to presence of ammoniated electrons.

Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because

Description : Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because

Last Answer : Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because A. HCl ... (3)` together give `O_(2)` that oxidises Pt

Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because

Description : Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because

Last Answer : Platinum metal (Pt) dissolves in aqua-regia but not in concentrated HCl ot `HNO_(3)` because A. HCl ... (3)` together give `O_(2)` that oxidises Pt

Which of the metal chloride is insoluble in cold water but dissolves in hot water ?

Description : Which of the metal chloride is insoluble in cold water but dissolves in hot water ?

Last Answer : Which of the metal chloride is insoluble in cold water but dissolves in hot water ? A. `BiCl_(3)` B. `SnCl_(4)` C. `PbCl_(2)` D. `AgCl`.

Write the name of a liquid in which phosphorous dissolves:?

Description : Write the name of a liquid in which phosphorous dissolves:?

Last Answer : Carbondisulphide

Which of the following hydrogen halides react with `AgNO_3` to give a precipitate that dissolves in hypo solution ? (I)HCl (II)HF (III)HI (IV)HBr

Description : Which of the following hydrogen halides react with `AgNO_3` to give a precipitate that dissolves in hypo solution ? (I)HCl (II)HF (III)HI (IV)HBr

Last Answer : Which of the following hydrogen halides react with `AgNO_3` to give a precipitate that dissolves in hypo solution ? (I) ... II),(I) D. (II),(IV),(III)

Silver nitrate solution when added to a colorless aqueous solution E forms a white precipitate which dissolves in excess of E. If the white precipitat

Description : Silver nitrate solution when added to a colorless aqueous solution E forms a white precipitate which dissolves in excess of E. If the white precipitat

Last Answer : Silver nitrate solution when added to a colorless aqueous solution E forms a white precipitate which dissolves in excess ... SO_(3)` D. `Na_(2)SO_(4)`

A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the aforementio

Description : A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the aforementio

Last Answer : A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution ... . `S^(2-)` D. `Cl^(-)`

A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a

Description : A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a

Last Answer : A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution ... (3)^(2-)` D. `S^(2-)`

`XeF_(6)` dissolves in anhydrous `HF` to give a good conducting solution which contains:

Description : `XeF_(6)` dissolves in anhydrous `HF` to give a good conducting solution which contains:

Last Answer : `XeF_(6)` dissolves in anhydrous `HF` to give a good conducting solution which contains: A. `H^(+)` and ` ... +)` and `F^(-)` ions D. none of these

If a student dissolves powdered sugar in a water in a beaker the student then places a strip of silver in the beaker what is the solute in this solution?

Description : If a student dissolves powdered sugar in a water in a beaker the student then places a strip of silver in the beaker what is the solute in this solution?

Last Answer : Sugar is the solute.

An egg sinks in soft water but floats in a concentrated solution of salt because – (1) Egg absorbs salt from the solution and expands (2) Albumin dissolves in salt solution and egg becomes lighter (3) The density of salt solution exceeds the density of eggs (4) Water has high surface tension

Description : An egg sinks in soft water but floats in a concentrated solution of salt because – (1) Egg absorbs salt from the solution and expands (2) Albumin dissolves in salt solution and egg becomes lighter (3) The density of salt solution exceeds the density of eggs (4) Water has high surface tension

Last Answer : (3) The density of salt solution exceeds the density of eggs Explanation: Following the density principle, the density of the egg compared to the density of the tap water is lesser (the density principle ... and that is why an egg sinks in soft water but floats in a concentrated solution of salt.

An egg sinks in soft water but floats in a concentrated solution of salt because (1) egg absorbs salt from the solution and expands (2) albumin dissolves in salt solution and egg becomes lighter (3) the density of salt solution exceeds the density of eggs (4) water has high surface tension

Description : An egg sinks in soft water but floats in a concentrated solution of salt because (1) egg absorbs salt from the solution and expands (2) albumin dissolves in salt solution and egg becomes lighter (3) the density of salt solution exceeds the density of eggs (4) water has high surface tension

Last Answer : the density of salt solution exceeds the density of eggs

What is alkali metal ?

Description : What is alkali metal ?

Last Answer : The first class elements of a periodic table are called alkali metals.

An element with an atomic number of 17 is - (1) an alkali metal (2) a rare gas (3) a halogen gas (4) a transition metal

Description : An element with an atomic number of 17 is - (1) an alkali metal (2) a rare gas (3) a halogen gas (4) a transition metal

Last Answer : (3) a halogen gas Explanation: Chlorine has atomic number of 17. It is a halogen gas along with fluorine (F), bromine (Br), iodine (I), and astatine (At).

Arrange the following in order of the increasing covalent character : MCl,MBr,MF,MI ( Where M=alkali metal)

Description : Arrange the following in order of the increasing covalent character : MCl,MBr,MF,MI ( Where M=alkali metal)

Last Answer : Ans. MF < MCI < MB < MI

Which alkali metal has the highest ionic radii ?

Description : Which alkali metal has the highest ionic radii ?

Last Answer : Ans.Cs.

Which alkali metal will have highest hydration enthalpy ?

Description : Which alkali metal will have highest hydration enthalpy ?

Last Answer : Ans. Li

When a cation is highly polarizing ? Which alkali metal cation has the highest polarizing power ?

Description : When a cation is highly polarizing ? Which alkali metal cation has the highest polarizing power ?

Last Answer : Ans. A cation is highly polarizing if its charge/size ratio is very high.Li+ has the highest polarizing power .

Name the alkali metal which forms only the normal oxide on heating with air ?

Description : Name the alkali metal which forms only the normal oxide on heating with air ?

Last Answer : Ans. Li.

Name the alkali metal which shows diagonal relationship with Mg?

Description : Name the alkali metal which shows diagonal relationship with Mg?

Last Answer : Ans.Li

Give point of resemblance of hydrogen with alkali metal.

Description : Give point of resemblance of hydrogen with alkali metal.

Last Answer : Ans: 1 like alkali metals hydrogen also has one electron in its valence shell 2 like alkali metals hydrogen loses its only electron to form proton(H+) 3 like alkalis metals hydrogen ... the same way as alkali metals are librated at the cathode during the electrolysis of their fused halides

Give reason for the appearance of colour in alkali metal halides.

Description : Give reason for the appearance of colour in alkali metal halides. 

Last Answer : Due to F-centres.

Within a given period of the periodic table, the element with the lowest ionization energy is: w) transition metal x) alkali metal y) halogen z) noble gas

Description : Within a given period of the periodic table, the element with the lowest ionization energy is: w) transition metal x) alkali metal y) halogen z) noble gas

Last Answer : ANSWER: X -- ALKALI METAL

State as to why: (a) A solution of Na2CO3 is alkaline? (b)alkali metals are prepared by electrolysis of their fused chlorides ? (c)sodium is found to be more useful than potassium ?

Description : State as to why: (a) A solution of Na2CO3 is alkaline? (b)alkali metals are prepared by electrolysis of their fused chlorides ? (c)sodium is found to be more useful than potassium ?

Last Answer : Ans. (a) It undergoes hydrolysis to produce a strong base NaOH . (b) When the aq. Solution of any alkali metal is subjected to electrolysis ,H2 instead of the alkali metal is produced at the ... of sugars and amino acids into the cells. Thus, sodium is found to be more useful than potassium.

Why do the the alkali metals give blue solution ,when treated with liq NH3?

Description : Why do the the alkali metals give blue solution ,when treated with liq NH3? 

Last Answer : The alkali metals dissolve in liquid ammonia giving deep blue solutions which are conducting in nature. The blue colour of the solution is due to the ammoniated electron which absorbs ... ammonia.) In concentrated solution, the blue colour changes to bronze colour and becomes diamagnetic.  

FeSO4 solution mixed with (NH4 ) 2 SO4 solution in 1 : 1 molar ratio gives the test of Fe2+ ion but CuSO4 solution mixed with aqueous ammonia in 1 : 4 molar ratio does not give the test of Cu2+ ion. Explain why ?

Description : FeSO4 solution mixed with (NH4 ) 2 SO4 solution in 1 : 1 molar ratio gives the test of Fe2+ ion but CuSO4 solution mixed with aqueous ammonia in 1 : 4 molar ratio does not give the test of Cu2+ ion. Explain why ?

Last Answer : When FeSO4 and (NH4 ) 2 SO4 solution are mixed in 1 : 1 molar ratio, a double salt is formed. It has the formula FeSO4 (NH4 ) 2 SO4 . 6 H2O. In aqueous solution, the salt dissociates. When CuSO4 and NH3 are mixed in the molar ratio of 1 : 4 in solution, a complex [Cu (NH3 ) 4 ] SO4 is formed.

On immersing gold pins in CuSO 4 solution for few minutes, you will observe (a) displacement reaction (b) the colour of solution fades away (c) the surface of gold pins acquire a black coating (d) No change

Description : On immersing gold pins in CuSO 4 solution for few minutes, you will observe (a) displacement reaction (b) the colour of solution fades away (c) the surface of gold pins acquire a black coating (d) No change

Last Answer : (d) No change

Methanol cannot be dried with anhydrous CaCl2 because - (1) CaCl2 dissolves in it (2) it is not good dehydrating agent (3) it forms a solid CaCl2 × 4CH3OH (4) it reacts with CH3OH

Description : Methanol cannot be dried with anhydrous CaCl2 because - (1) CaCl2 dissolves in it (2) it is not good dehydrating agent (3) it forms a solid CaCl2 × 4CH3OH (4) it reacts with CH3OH

Last Answer : (3) it forms a solid CaCl2 × 4CH3OH

Potassium Permanganate is used for purifying drinking water, because ________. (1) It is a reducing agent (2) It is an oxidising agent (3) It is a sterilising agent (4) It dissolves the impurities of water

Description : Potassium Permanganate is used for purifying drinking water, because ________. (1) It is a reducing agent (2) It is an oxidising agent (3) It is a sterilising agent (4) It dissolves the impurities of water

Last Answer : (2) It is an oxidising agent Explanation: Potassium permanganate is a point-of-entry water treatment method that oxidizes dissolved iron, mancianese, and hydrogen sulfide into solid particles that are filtered ... to control iron bacteria growth in wells. It is an oxidant, but a poor disinfectant.

Gold dissolves in – (1) Hydrochloric acid (2) Nitric acid (3) Aqua-regia (4) Acetic acid

Description : Gold dissolves in – (1) Hydrochloric acid (2) Nitric acid (3) Aqua-regia (4) Acetic acid

Last Answer : (3) Aqua-regia Explanation: Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. It was named so because it can dissolve the so-called royal or noble metals, gold and platinum.

Potassium Permanganate is used for purifying drinking water, because - (1) it dissolves the impurities of water (2) It is a sterilizing agent (3) It is an oxidising agent (4) It is a reducing agent

Description : Potassium Permanganate is used for purifying drinking water, because - (1) it dissolves the impurities of water (2) It is a sterilizing agent (3) It is an oxidising agent (4) It is a reducing agent

Last Answer : (3) It is an oxidising agent Explanation: Potassium permanganate is a point-of-entry treatment method that oxidizes dissolved iron, manganese, and hydrogen sulfide into solid particles that are filtered out of the water.

A compound undergoes reduction with LiAlH4. It also dissolves in aqueous NaOH from which it can be recovered by addition of HCl. The compound is (a) a carboxylic acid (b) an ester (c) an acid anhydride (d) an alcohol

Description : A compound undergoes reduction with LiAlH4. It also dissolves in aqueous NaOH from which it can be recovered by addition of HCl. The compound is (a) a carboxylic acid (b) an ester (c) an acid anhydride (d) an alcohol

Last Answer : a carboxylic acid

Potassium Permanganate is used for purifying drinking water, because_________ (1) It is a reducing agent (2) It is an oxidising agent (3) It is a sterilising agent (4) It dissolves the impurities of water

Description : Potassium Permanganate is used for purifying drinking water, because_________ (1) It is a reducing agent (2) It is an oxidising agent (3) It is a sterilising agent (4) It dissolves the impurities of water 

Last Answer :  It is an oxidising agent

Gold dissolves in (1) Hydrochloric acid (2) Nitric acid (3) Aqua-regia (4) Acetic acid

Description : Gold dissolves in (1) Hydrochloric acid (2) Nitric acid (3) Aqua-regia (4) Acetic acid

Last Answer : Aqua-regia

Four identical samples of a metal are heated to different temperatures. Based on the colors of their incandescences, which sample is the hottest? The sample that is: w) blue-white x) bright red y) yellow z) orange

Description : Four identical samples of a metal are heated to different temperatures. Based on the colors of their incandescences, which sample is the hottest? The sample that is: w) blue-white x) bright red y) yellow z) orange

Last Answer : ANSWER: W -- BLUE-WHITE

Which of the following is a super-cooled liquid? (1) Ice-cream (2) Ammonia (3) Glass (4) Wood

Description : Which of the following is a super-cooled liquid? (1) Ice-cream (2) Ammonia (3) Glass (4) Wood

Last Answer : (3) Glass Explanation: Glass is considered to be a supercooled liquid due to its lack of a first-order phase transition where certain thermodynamic variables such as volume, entropy ... where the intensive thermodynamic variables such as the thermal expansivity and heat capacity are discontinuous.

Give reasons i) H2O is a liquid but H2S a gas. ii) Ammonia has higher boiling point than phosphine ii) Krypton & xenon make compounds.

Description : Give reasons i) H2O is a liquid but H2S a gas. ii) Ammonia has higher boiling point than phosphine ii) Krypton & xenon make compounds.

Last Answer : Ans: i) Hydrogen bond is found in H2O but not in H2S.  ii) Hydrogen bond is found in NH3 but not in PH3.  iii) Because they have low ionization energy.

Which of the following is a super-cooled liquid? (1) Ice-cream (2) Ammonia (3) Glass (4) Wood

Description : Which of the following is a super-cooled liquid? (1) Ice-cream (2) Ammonia (3) Glass (4) Wood

Last Answer : Glass

One property of ammonia is – (1) It is insoluble in water (2) it is a odourless gas (3) It is a yellowish gas (4) Its aqueous solution turns red litmus blue

Description : One property of ammonia is – (1) It is insoluble in water (2) it is a odourless gas (3) It is a yellowish gas (4) Its aqueous solution turns red litmus blue

Last Answer : (4) Its aqueous solution turns red litmus blue Explanation: The main use of litmus is to test whether a solution is acidic or basic. For instance, ammonia gas, which is alkaline, colours the red litmus paper blue.

Which of the following is the strongest base in aqueous solution? (1) Diethylamine (2) Triethylamine (3) Ammonia (4) Ethylamine

Description : Which of the following is the strongest base in aqueous solution? (1) Diethylamine (2) Triethylamine (3) Ammonia (4) Ethylamine

Last Answer : (1) Diethylamine Explanation: Amines are organic derivatives of ammonia, in which one, two, or all three of the hydrogens of ammonia are replaced by organic groups. All aliphatic primary amines are stronger bases than ammonia.

Why ammonia solution is used for the cure of honey bee sting, whereas vinegar is used for curing sting of wasp?

Description : Why ammonia solution is used for the cure of honey bee sting, whereas vinegar is used for curing sting of wasp?

Last Answer : Ans: Honey bee sting is acidic so to neutralize its effect we use a basic ammonia solution. Whereas sting of wasp is alkaline so we use vinegar( weak acid) for cure.

Which of the following is a strong electrolyte in aqueous solution. w) ammonia x) coffee y) Gatorade z) corn syrup

Description : Which of the following is a strong electrolyte in aqueous solution. w) ammonia x) coffee y) Gatorade z) corn syrup

Last Answer : ANSWER: Y -- GATORADE