1276 + Interview Questions in S-BLOCK-ELEMENTS IN GENERAL AWARENESS Page 19 InterviewSolution

901.	which of the following is used to make visible upper tract in an X-ray photograph?A. MilkshakeB. bnrium enemaC. `BaSO_(4)` suspensionD. `CaSO_(4)`
Answer» Correct Answer - 1

Discussion

902.	Colour of iodine solution is discharged by shaking it with aqueous solution of sodium thiosulphate.A. `H_(2)SO_(4)`B. Sodium thisulphideC. Sodium sulphateD. Sodium thisulphate
Answer» Correct Answer - D

Discussion

903.	Sodium thiosulphate, `Na_(2)S_(2)O_(3).5H_(2)O` is used in photography toA. Reduce silver bromide to metallic silverB. Convert metallic silver to silver saltC. Remove undecomposed `AgBr` as a soluble silver thiosulphate complexD. Remove unreduced silver
Answer» Correct Answer - C `AgBr+2Na_(2)SO_(3) rarr Na_(3)[Ag(S_(2)O_(3))_(3)]+NaBr`

Discussion

904.	Sodium thiosulphate `(Na_(2)S_(2)O_(3).5H_(2)O)` is used in photography toA. Reduce AgBr to metallic Ag.B. Remove reduce AgC. Remove undecomposed AgBr as a soluble complexD. Convert metallic Ag
Answer» Correct Answer - C

Discussion

905.	Acidified solution f sodium thiosulphate are unstable because:A. they have the tendency to oxidise the acid.B. they have the tendency to disproportionate.C. they have the tendency to reduce the acid.D. they have strong S-S bonds.
Answer» Correct Answer - B

Discussion

906.	Which of the following metals can easily be cut with a knife?A. MagnesiumB. BariumC. AluminiumD. Sodium
Answer» Correct Answer - D

Discussion

907.	On hydrolysis of Rubidium superoxide, which of the following products are formed?A. RbOHB. `H_(2)O_(2)`C. `O_(2)`D. `H_(2)O`
Answer» Correct Answer - A::B::C `2RbO_(2)+2H_(2)Orarr2RbOH+H_(2)O_(2)+O_(2)`

Discussion

908.	On combustion in excess air, Li forms :A. `Li_(2)O`B. `Li_(2)O_(2)`C. `LiO_(2)`D. `LiO_(3)`
Answer» Correct Answer - A::B Mainly `Li_(2)O` is formed, plus some peroxide, `Li_(2)O_(2)` is also formed.

Discussion

909.	The correct order of degree of hydration of `M^(+)` ions of alkali metals is :A. `Li^(+)ltK^(+)ltNa^(+)ltRb^(+)ltCs^(+)`B. `Li^(+)ltNa^(+)ltK^(+)ltRb^(+)ltCs^(+)`C. `Cs^(+)ltRb^(+)ltK^(+)ltNa^(+)ltLi^(+)`D. `Cs^(+)ltRb^(+)ltNa^(+)ltK^(+)ltLi^(+)`
Answer» Correct Answer - C

Discussion

910.	When excess carbon dioxide gas is passed through an aqueous solution of potassium super oxide a product (X) is formed . The correct statement regarding X isA. The anion present in crystalline (X) exist as a dimer due to hydrogen bondsB. (X) Cannot be isolated in solid stateC. (X) is generally called washing sodaD. Gives thermally unstable carbonate on heating
Answer» Correct Answer - A

Discussion

911.	Select correct statement :A. Interstitial carbides are formed by metalloids like Si and BB. SiC and `B_(4)C` are covalent carbides.C. `B_(4)C` on hyrolysis give methane.D. VC, WC are ionic carbides.
Answer» Correct Answer - B

Discussion

912.	When excess potassium super oxide is placed in a container containing `CO_(2)` , thenA. The pressure of the container decreasesB. The pressure of the container increasesC. The pressure of the container remains constantD. The pressure of the container first increases and then decreases
Answer» Correct Answer - B

Discussion

913.	Methanides are:A. `Mg_(2)C_(3),BeC, Al_(4)C_(3)" and " CaC_(2)`B. `Mg_(2)C_(3),BeC, " and " Al_(4)C_(3)`C. `Be_(2)C, Al_(4)C_(4) " and " CaC_(2)`D. `Be_(2)C " and " Al_(4)C_(3)`
Answer» Correct Answer - D

Discussion

914.	Which of the following statement is incorrect ?A. Mg and Ca both impart characteristic color to the flame.B. The metallic radius of Na is greater than that of Mg.C. Metallic bond of Mg is stronger than the metallic bond in NaD. Melting point of Mg is greater than melting poing of Ca.
Answer» Correct Answer - 1 Mg does not impart color to the flame but sodium give goldent yellow color.

Discussion

915.	`KO_(2)` ( potassium super oxide ) is used in space and submarines because it `:`A. absorbs `CO_(2)` and increses `O_(2)` contentsB. eliminates moisture and increses `CO` contentsC. absorbs `CO_(2)`onlyD. produces ozone
Answer» Correct Answer - 1 `2KO_(2)+CO_(2)rarrK_(2)CO_(3)+(3)/(2)O_(2)`

Discussion

916.	Sodium peroxide is used to purify the an m submarines and confined spaces because:A. it remoces `CO_(2)` and produces `O_(2)`B. it decompses to from `Na_(2)O`C. it reacts with oxygen to from sodium superoxideD. all of these
Answer» Correct Answer - A

Discussion

917.	Which of the following is formed by the action of water on sodium peroxide ?A. `H_(2)`B. `N_(2)`C. `O_(2)`D. `CO_(2)`
Answer» Correct Answer - C

Discussion

918.	Which is not a solid?A. `KHCO_(3)`B. `Na_(2)CO_(3)`C. `Ca(HCO_(3))_(2)`D. LiCl
Answer» Correct Answer - C

Discussion

919.	Be forms `[BeF_(4)]^(2-)`, but `Al` forms `[AiF_(6)]^(3-)`. Reason (R ): Be does not have `d`-orbitals in the valence shell but `Al` has.A. Statement : 1 is ture, Statement 2 is also ture, Statement 2 is the correct explanation of statement 1B. Statement 1 is ture, Statement 2 is also ture, statement 2 is not the correct explanation of statement 1C. Statement 1 is true, Statement 2 is false.D. Statement 1 is also false, Statement 2 is ture
Answer» Correct Answer - A Statement-2 is the correct explanation for statement-1

Discussion

920.	The best route for the preparation of `BeF_(2)` is :A. thermal decomposition of `(NH_(4))_(2)" BeF_(4)`B. `BeO+C+F_(2)overset(600-800K)hArrBeF_(2)+CO`C. `Be+F_(2)overset(High T)rarrBeF_(2)`D. all of the above
Answer» Correct Answer - A

Discussion

921.	Statement -1: Both Be and Al can form complexes such as `BeF_(4)^(2-)` and `AlF_(6)^(3-)` respectivelly. `BeF_(6)^(3-)` is not formed. Statement -2: In case of Be, no vacant dorbitals are present in its outermost shell.A. Both Statement -1 and Statement-2 are true and Statement-2 is the correct explanation of Statement -1B. Both Statement -1 and Statement-2 are true and Statement-2 is the not correct explanation of Statement -1C. Statement-1 is true but Statement -2 is falseD. Statement-1 is false but Statement -2 is true
Answer» Correct Answer - A

Discussion

922.	The covalent halide among the followingA. `BeF_(2)`B. `SrCl_(2)`C. `CaCl_(2)`D. `BaCl_(2)`
Answer» Correct Answer - 1

Discussion

923.	The compoud formed when an alkyl halide reacts with magnesium in ether isA. Grignard reagentB. AntisepticC. AnaestheticD. Antipyretic
Answer» Correct Answer - 1

Discussion

924.	Which one is the highest melting halide ?A. NaClB. LiClC. LiBrD. NaI
Answer» Correct Answer - A LiCl and LiBr are covalent and hence their melting points are low. Amongest NaCl and Nal, NaCl has higher ionic character (becaue `Cl^(-)` is smaller than `I^(-)` ion) and hence has higher lattice energy than naI. Therefore NaCl has the highest m.p.

Discussion

925.	When `NaOH` crystals are left in open air, they acquire a fluid layer around each crystal asA. They start meltingB. They absorb moisture from airC. They react with air to form a liquid compoundD. They absorb `O_(2)` from air
Answer» Correct Answer - B `NaOH` is a deliquescent white crystalline solide. It absorbs moisture from the atmosphere.

Discussion

926.	Chemical A is used for water softening to remove temporary hardness. A reacts with sodium carbonate to generate caustic soda. When `CO_(2)` is bubbled through a solution of A, it turns cloudy. What is the chemical formula of A ?A. `CaCO_(3)`B. `CaO`C. `Ca(OH)_(2)`D. `Ca(HCO_(3))_(2)`
Answer» Correct Answer - D `Ca(HCO_(3))_(2)` removes temporary hardness from water.

Discussion

927.	Which is used in purification of air in the space craft.A. Slaked limeB. Quick limeC. Pottassium superoxideD. `CaCI_(2)`
Answer» Correct Answer - C

Discussion

928.	Compounds of alkaline earth metals are generally less soluble in water than that of alkali metals because of:-A. High hydration energyB. More covalent characterC. More ionic characterD. Less lattice energy
Answer» Correct Answer - B

Discussion

929.	Which of the following alkaline earth metal sulphate is least soluble in water:-A. `BaSO_(4)`B. `CaSO_(4)`C. `BeSO_(4)`D. `SrSO_(4)`
Answer» Correct Answer - A

Discussion

930.	Which one of the following is not an ore of magnesium ?A. CarnaliteB. DolomiteC. CalamineD. Sea water
Answer» Correct Answer - 3

Discussion

931.	`K` and `Cs` are used in photoelectric cells. `K` and `Cs` emit electrons on exposure to light.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertionC. If assertion is true but reason is false.D. If assertion is false but reason is true.
Answer» Correct Answer - a `K` and `Cs` emit electrons on exposure of light due to low ionisation potential.

Discussion

932.	Statement-1: Potassium and caesium are used in photo-electric cells. Statement-2: Potassium and caesium emit electrons on exposure to light above certain minimum frequency.A. Statement-1 is True, Statement-2 is True. Statement-2 is a correct explanation for Statement-1.B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1.C. Statement-1 is True, Statement-2 is False.D. Statement-1 is False, Statement-2 is True.
Answer» Correct Answer - A

Discussion

933.	Caesium oxide will beA. Very stronly basicB. AcidicC. Wealkly basicD. Amphoteric
Answer» Correct Answer - A

Discussion

934.	Why are potassium and caesium, rather lithium used in photoelectric cells?
Answer» The ionisation enthalpy of lithium is quite high. The photons are not in a position to reject electorns form the surface of lithium metal. Therefore, photoelectric effect is not noticed. However, both potassium and cesium have comparatively low ionisation enthalpies. This means that the electrons can quite easily be ejected from the surface of these metals when photos of certain minimum frequency (threshold frequencey `v^(0)`)strike against their surface.

Discussion

935.	Match the list I and list II and select the correct answer using the codes given below the lists. A. A-6,B-1,C-4,D-3B. A-6,B-1,C-4,D-1C. A-6,B-1,C-5,D-2D. A-5,B-2,C-4,D-3
Answer» Correct Answer - A

Discussion

936.	Which of the following statements is incorrect:-A. `NaHCO_(3)` on heating gives `Na_(2)CO_(3)`B. Pure sodium metal dissolves in liquid ammonia to give blue solutionC. `NaOH` reacts with glass to give sodium silicateD. Aluminium reacts with excess `NaOH` to give `AI(OH)_(3)`
Answer» Correct Answer - D

Discussion

937.	Rede the following statements and choose true (T) or false (F). (i) Lithopone is used as pigment. (ii) Crude common salt is hygroscpic because of impurities of `MgCl_92)` and `CaCl_(2)` (iii) Sylvine is an ore of potassium. (iv) Lithium imparts sky-blue colour to the flame. v) In the electrolsis of NaCl solution for the manufacure of NaOH, the ion discharged at cathode is `H^(o+)` . (vi) Lithium is used in photoelectric cells.A. TTFFTTB. TTTTFTEC. FTFTFTD. TTTFFT
Answer» Correct Answer - B

Discussion

938.	Identify the false statementA. both `Na_(2)CO_(3)` and `K_(2)CO_(3)` are obtained by solvay processB. meltallic sodium is used for drying diethyl ether but not ethyl alcohol.C. The sftness of Group IA metals increases down the group.D. LiCl is more covalent than LiF
Answer» Correct Answer - A

Discussion

939.	Match List-I with List-II for the composition of substances and select the correct answer using the code gives below the lists:- `{:(List-I,List-II),("Substances","Composition"),((A)"Plaster of Paris",(i)CaSO_(4).2H_(2)O),((B)"Epsomite",(ii)CaSO_(4).(1)/(2)H_(2)O),((C)"Kieserite",(iii)MgSO_(4).7H_(2)O),((D)"Gypsum",(iv)MgSO_(4).H_(2)O),(,(v)CaSO_(4)):}`A. `{:((A),(B),(C),(D).),((iv),(ii),(ii),(i).):}`B. `{:((A),(B),(C),(D).),((iii),(iv),(i),(ii).):}`C. `{:((A),(B),(C),(D).),((ii),(iii),(iv),(i).):}`D. `{:((A),(B),(C),(D).),((i),(ii),(iii),(v).):}`
Answer» Correct Answer - C

Discussion

940.	Crude sodium chloride contains :A. `Na_(2)SO_(4)`B. `CaSO_(4)`C. `CaCl_(2)`D. `MgCl_(2)`
Answer» Correct Answer - A::B::C::D All are impurities.

Discussion

941.	Passivity is exhibited by i) Be ii)Mgiii)Aliv)BA. I,iiB. ii,iiiC. I,iiiD. ii,iv
Answer» Correct Answer - 3

Discussion

942.	Choose the correct answer A. A-4,B-3,C-2,D-1B. A-3,B-4,C-1,D-2C. A-2,B-3,C-4,D-1D. A-1,B-2,C-3,D-4
Answer» Correct Answer - A

Discussion

943.	`A+H_(2)Oto NaOH` `A underset(400^(@)C)overset(O_(2))rarrBunderset(at25^(@)C)overset(H_(2)O)rarrNaOH+O_(2),` B is used for oxygenating in submarines A and B are respectively.A. `Na_(2)O_(2)` and `Na_(2)O`B. `Na_(2)O` and `Na_(2)O_(2)`C. `Na_(2)O_(2)` and `O_(2)`D. `Na_(2)O` and `O_(2)`
Answer» Correct Answer - B

Discussion

944.	Which one of the following salts gives aqueous solution which is weakly basic ?A. `NaHCO_(3)`B. `NaHSO_(4)`C. `NaCl`D. `NH_(4)HCO_(3)`
Answer» Correct Answer - A `underset("acid)")underset("base and weak")underset("(Salt of strong") (NaHCO_(3)) rarr Na^(+)+underset(OH^(-)+CO_(2))underset(darr)(HCO_(3)^(-))`

Discussion

945.	Which of the following may be a use of `Na_(2)CO_(3).10H_(2)O`?A. Water softening, laundering and cleaningB. Manufacture of glass, soap, borax and caustic sodaC. Paper, paint and textile industryD. An important laboratory reagent both in qualitative and quantitative analysis
Answer» Correct Answer - A::B::C::D

Discussion

946.	Assertion: In the solution of K in liquid `NH_(3)`, blue colour appears. Reason: K reacts with `NH_(3)` to form `KNH_(2)`A. If both Assertion & Reason are True & the Reason is a correct explanation of the AssertionB. If both Assertion & Reason are True but Reason is not a correct explanation of the AssertionC. If Assertion is True but the Reason is FalseD. If both Assertion & Reason are False
Answer» Correct Answer - B `K+NH_(3)("liq")rarr[K^(+)(NH_(3))_(x)]+underset("ammoniate electron")underset("blue color due to")([(e^(-)CNH_(3))_(y)])` `[K(NH_(3))_(x)]^(+)rarrKNH_(2)+H^(+)` `H^(+) + e^(-) rarr H` `H + H rarr H_(2)` Both are correct

Discussion

947.	`NaOH+CO oversetr(200^(@)C)underset(5-10 atm)rarr A`. The product A is:A. `NaHCO_(3)`B. `Na_(2)CO_(3)`C. HCOONaD. `H_(2)CO_(3)`
Answer» Correct Answer - C

Discussion

948.	False statement about `Na_(2)CO_(3)10H_(2)O` isA. It contains dative, covalent and ionic bondsB. It removes only permanent hardness of waterC. It does not give pink colour with phenolphthaleinD. All are false
Answer» Correct Answer - D

Discussion

949.	Sodium gives blue colour in `NH_(3)` solution. This blue colour is due toA. ammoniated `Na^(+)`B. `ammoniated Na^(-)`C. ammoniated `e^(-)`D. `Na^(+)//N^(-)` pair.
Answer» Correct Answer - C Blue colour is due to ammoniated electron.

Discussion

950.	When `CO` is heated with `NaOH` under pressure, we getA. `Na_(2)CO_(3)`B. `NaHCO_(3)`C. `HCOONa`D. None
Answer» Correct Answer - C `NaOH +CO underset(5-10atm)overset(150^(@)-200^(@)C)rarrHCOONa`

Discussion

Explore topic-wise InterviewSolutions in .

which of the following is used to make visible upper tract in an X-ray photograph?A. MilkshakeB. bnrium enemaC. `BaSO_(4)` suspensionD. `CaSO_(4)`

Colour of iodine solution is discharged by shaking it with aqueous solution of sodium thiosulphate.A. `H_(2)SO_(4)`B. Sodium thisulphideC. Sodium sulphateD. Sodium thisulphate

Sodium thiosulphate, `Na_(2)S_(2)O_(3).5H_(2)O` is used in photography toA. Reduce silver bromide to metallic silverB. Convert metallic silver to silver saltC. Remove undecomposed `AgBr` as a soluble silver thiosulphate complexD. Remove unreduced silver

Sodium thiosulphate `(Na_(2)S_(2)O_(3).5H_(2)O)` is used in photography toA. Reduce AgBr to metallic Ag.B. Remove reduce AgC. Remove undecomposed AgBr as a soluble complexD. Convert metallic Ag

Acidified solution f sodium thiosulphate are unstable because:A. they have the tendency to oxidise the acid.B. they have the tendency to disproportionate.C. they have the tendency to reduce the acid.D. they have strong S-S bonds.

Which of the following metals can easily be cut with a knife?A. MagnesiumB. BariumC. AluminiumD. Sodium

On hydrolysis of Rubidium superoxide, which of the following products are formed?A. RbOHB. `H_(2)O_(2)`C. `O_(2)`D. `H_(2)O`

On combustion in excess air, Li forms :A. `Li_(2)O`B. `Li_(2)O_(2)`C. `LiO_(2)`D. `LiO_(3)`

The correct order of degree of hydration of `M^(+)` ions of alkali metals is :A. `Li^(+)ltK^(+)ltNa^(+)ltRb^(+)ltCs^(+)`B. `Li^(+)ltNa^(+)ltK^(+)ltRb^(+)ltCs^(+)`C. `Cs^(+)ltRb^(+)ltK^(+)ltNa^(+)ltLi^(+)`D. `Cs^(+)ltRb^(+)ltNa^(+)ltK^(+)ltLi^(+)`

Select correct statement :A. Interstitial carbides are formed by metalloids like Si and BB. SiC and `B_(4)C` are covalent carbides.C. `B_(4)C` on hyrolysis give methane.D. VC, WC are ionic carbides.

When excess potassium super oxide is placed in a container containing `CO_(2)` , thenA. The pressure of the container decreasesB. The pressure of the container increasesC. The pressure of the container remains constantD. The pressure of the container first increases and then decreases

Methanides are:A. `Mg_(2)C_(3),BeC, Al_(4)C_(3)" and " CaC_(2)`B. `Mg_(2)C_(3),BeC, " and " Al_(4)C_(3)`C. `Be_(2)C, Al_(4)C_(4) " and " CaC_(2)`D. `Be_(2)C " and " Al_(4)C_(3)`

Which of the following statement is incorrect ?A. Mg and Ca both impart characteristic color to the flame.B. The metallic radius of Na is greater than that of Mg.C. Metallic bond of Mg is stronger than the metallic bond in NaD. Melting point of Mg is greater than melting poing of Ca.

`KO_(2)` ( potassium super oxide ) is used in space and submarines because it `:`A. absorbs `CO_(2)` and increses `O_(2)` contentsB. eliminates moisture and increses `CO` contentsC. absorbs `CO_(2)`onlyD. produces ozone

Sodium peroxide is used to purify the an m submarines and confined spaces because:A. it remoces `CO_(2)` and produces `O_(2)`B. it decompses to from `Na_(2)O`C. it reacts with oxygen to from sodium superoxideD. all of these

Which of the following is formed by the action of water on sodium peroxide ?A. `H_(2)`B. `N_(2)`C. `O_(2)`D. `CO_(2)`

Which is not a solid?A. `KHCO_(3)`B. `Na_(2)CO_(3)`C. `Ca(HCO_(3))_(2)`D. LiCl

The best route for the preparation of `BeF_(2)` is :A. thermal decomposition of `(NH_(4))_(2)" BeF_(4)`B. `BeO+C+F_(2)overset(600-800K)hArrBeF_(2)+CO`C. `Be+F_(2)overset(High T)rarrBeF_(2)`D. all of the above

The covalent halide among the followingA. `BeF_(2)`B. `SrCl_(2)`C. `CaCl_(2)`D. `BaCl_(2)`

The compoud formed when an alkyl halide reacts with magnesium in ether isA. Grignard reagentB. AntisepticC. AnaestheticD. Antipyretic

Which one is the highest melting halide ?A. NaClB. LiClC. LiBrD. NaI

When `NaOH` crystals are left in open air, they acquire a fluid layer around each crystal asA. They start meltingB. They absorb moisture from airC. They react with air to form a liquid compoundD. They absorb `O_(2)` from air

Chemical A is used for water softening to remove temporary hardness. A reacts with sodium carbonate to generate caustic soda. When `CO_(2)` is bubbled through a solution of A, it turns cloudy. What is the chemical formula of A ?A. `CaCO_(3)`B. `CaO`C. `Ca(OH)_(2)`D. `Ca(HCO_(3))_(2)`

Which is used in purification of air in the space craft.A. Slaked limeB. Quick limeC. Pottassium superoxideD. `CaCI_(2)`

Compounds of alkaline earth metals are generally less soluble in water than that of alkali metals because of:-A. High hydration energyB. More covalent characterC. More ionic characterD. Less lattice energy

Which of the following alkaline earth metal sulphate is least soluble in water:-A. `BaSO_(4)`B. `CaSO_(4)`C. `BeSO_(4)`D. `SrSO_(4)`

Which one of the following is not an ore of magnesium ?A. CarnaliteB. DolomiteC. CalamineD. Sea water

Caesium oxide will beA. Very stronly basicB. AcidicC. Wealkly basicD. Amphoteric

Why are potassium and caesium, rather lithium used in photoelectric cells?

Match the list I and list II and select the correct answer using the codes given below the lists. A. A-6,B-1,C-4,D-3B. A-6,B-1,C-4,D-1C. A-6,B-1,C-5,D-2D. A-5,B-2,C-4,D-3

Which of the following statements is incorrect:-A. `NaHCO_(3)` on heating gives `Na_(2)CO_(3)`B. Pure sodium metal dissolves in liquid ammonia to give blue solutionC. `NaOH` reacts with glass to give sodium silicateD. Aluminium reacts with excess `NaOH` to give `AI(OH)_(3)`

Identify the false statementA. both `Na_(2)CO_(3)` and `K_(2)CO_(3)` are obtained by solvay processB. meltallic sodium is used for drying diethyl ether but not ethyl alcohol.C. The sftness of Group IA metals increases down the group.D. LiCl is more covalent than LiF

Crude sodium chloride contains :A. `Na_(2)SO_(4)`B. `CaSO_(4)`C. `CaCl_(2)`D. `MgCl_(2)`

Passivity is exhibited by i) Be ii)Mgiii)Aliv)BA. I,iiB. ii,iiiC. I,iiiD. ii,iv

Choose the correct answer A. A-4,B-3,C-2,D-1B. A-3,B-4,C-1,D-2C. A-2,B-3,C-4,D-1D. A-1,B-2,C-3,D-4

`A+H_(2)Oto NaOH` `A underset(400^(@)C)overset(O_(2))rarrBunderset(at25^(@)C)overset(H_(2)O)rarrNaOH+O_(2),` B is used for oxygenating in submarines A and B are respectively.A. `Na_(2)O_(2)` and `Na_(2)O`B. `Na_(2)O` and `Na_(2)O_(2)`C. `Na_(2)O_(2)` and `O_(2)`D. `Na_(2)O` and `O_(2)`

Which one of the following salts gives aqueous solution which is weakly basic ?A. `NaHCO_(3)`B. `NaHSO_(4)`C. `NaCl`D. `NH_(4)HCO_(3)`

Which of the following may be a use of `Na_(2)CO_(3).10H_(2)O`?A. Water softening, laundering and cleaningB. Manufacture of glass, soap, borax and caustic sodaC. Paper, paint and textile industryD. An important laboratory reagent both in qualitative and quantitative analysis

`NaOH+CO oversetr(200^(@)C)underset(5-10 atm)rarr A`. The product A is:A. `NaHCO_(3)`B. `Na_(2)CO_(3)`C. HCOONaD. `H_(2)CO_(3)`

False statement about `Na_(2)CO_(3)10H_(2)O` isA. It contains dative, covalent and ionic bondsB. It removes only permanent hardness of waterC. It does not give pink colour with phenolphthaleinD. All are false

Sodium gives blue colour in `NH_(3)` solution. This blue colour is due toA. ammoniated `Na^(+)`B. `ammoniated Na^(-)`C. ammoniated `e^(-)`D. `Na^(+)//N^(-)` pair.

When `CO` is heated with `NaOH` under pressure, we getA. `Na_(2)CO_(3)`B. `NaHCO_(3)`C. `HCOONa`D. None