94420 + Interview Questions in Chemistry in Class 12 Page 1825 InterviewSolution

91201.	A broad spectrum antibiotic is :
Answer» Paracetamol Ranitidine Aspirin Chloromphenicol Answer :D

Discussion

91202.	A bridging ligand possesses:
Answer» Polydentate or monodentate nature TWO or more DONOR centres The tendency to get itself attached to two METAL ions All Answer :D

Discussion

91203.	A bidentale ligand is
Answer» Polydentate nature Two or more donor centres The TENDENCY to get itself attached to two metal IONS NONE of these Solution :

Discussion

91204.	A brick red colour is imparted by a
Answer» CA salt Sr salt Na salt Co salt Solution :Calcium SALTS impart brick RED colour to the FLAME

Discussion

91205.	(a) BrHC=CHBr exists as two diastereomers draw them and compare their dipole moment. (b) trans-Butenedioic acid has higher melting point than cis-butendioic acid. Why? (c) Draw the cis cand trans structure of hex-2-ene. Which isomer will have higher b.p. and why ?
Answer» Answer :`(##RES_CHM_SIM_E01_007_A01##)` dipole moment :`II GT 1` (b) Because of good packing of trans isomers. `(##RES_CHM_SIM_E01_007_A02##)` CIS has higher BOILING point due to more polarity.

Discussion

91206.	A breaker contains a solution of substance 'A'. Precipitation of substance 'A' takes place when small amount of 'A' is added to the solution. The solution is ………….
Answer» saturated supersturated unsaturated concentrated Solution :In saturated solution, more substance does not DISSOLVE. In a SUPERSATURATED solution, substance STARTS PRECIPITATING out.

Discussion

91207.	A+Brarr"Product",(dx)/(dt)=k[A]^(a)[B]^(b) If ((dx)/(dt))=k, then order of reaction is :
Answer» 4 2 1 0 Answer :D

Discussion

91208.	A+BrarrCH_(3)-OC(CH_(3))_(3)overset(HI)rarrX+Y Correct statement among the following is
Answer» A and B are `CH_(3)Ona` and `(CH_(3))_(3)` CBr X and Y are `CH_(3)I` and `(CH_(3))_(3)COH` X and Y are `CH_(3)OH` and `(CH_(3))_(3)` CI A and B are `CH_(3)OH` and `(CH_(3))_(3)` COH Answer :C

Discussion

91209.	A box is divided by a thin partition into equal compartments and they are filled with an equal number of hydrogen and heavy hydrogen molecules respectively. If the pressure in the hydrogen compartment is 1 cm Hg, what is the pressure in the other compartment ? What will be the pressure if the partition is removed ?
Answer» SOLUTION :1 CM HG, 1 cm Hg

Discussion

91210.	A box contains some identical red coloured balls, labelled as A, each weighing 2 grams. Another box contains identical blue coloured balls, labelled as B, each weighing 5 grams. Consider the combinations AB, AB_(2),A_(2)B and A_(2)B_(3) and show that law of multiple proportions is applicable.
Answer» Solution :`{:("Comination",AB,AB_(2),A_(2)B,A_(2)B_(3)),("Mass of A (g)",2,2,4,4),("Mass of B (g)",5,10,5,15):}` `therefore` Masses of B which combine with fixed mass of A (say 4 g ) will be 10 g, 20 g, 5 g, i.e., they are in the RATIO `2:4:1:3` which is a simple whole number ratio. Hence, the law of multiple proportions is APPLICABLE.

Discussion

91211.	A box contains 12xx10^(22) number of oxygen atoms. Find moles of O-atoms? (N_(A)=6xx10^(23))
Answer» ANSWER :`(##ALN_NC_CHM_MC_E01_001_A01##)` `0.2

Discussion

91212.	A box is divided into two equal compartments by a thin partition and they are filled with gases P and Q respectively . The two compartments have a pressure of 250 torr each. The pressure after removing the partition will be equal to
Answer» 500 TORR 125 torr 250 torr 5000 torr. Answer :C

Discussion

91213.	A bottle, which contains 200 ml of 0.1KOH, absorbs 1 millimole of CO_(2) from the air, If the solution is then treated with standard acid using phenolphthalein indicator, the normally will be
Answer» 0.095 N 0.1 N 0.2 N 0.036 N ANSWER :A

Discussion

91214.	A bottle of H_(3)PO_(4) solution contains 70% acid. If the density of the solution is 1.54 gcm^(-3) , the volumeof the H_(3)PO_(4) solution required to prepare 1L of IN solution is .
Answer» 90 mL 45mL 30mL 23mL Answer :C

Discussion

91215.	A bottle of milk stored at 300 K sours in 36 hours. When stored in a refrigerator at 275 K it sours in 360 hours, Calculate the energy of activation of the reaction involved in the souring process.
Answer» SOLUTION :`63.18 ` KJ / MOL

Discussion

91216.	A bottle of dry NH_3 and bottle of dry HCl connected through a long tube are opened simultaneously at both ends, the white (NH_4Cl) ring first formed will be :
Answer» At the CENTRE of the TUBE Near the HCl bottle Near the ammonia bottle Throughout the length of the tube ANSWER :B

Discussion

91217.	A sample of H_(2) SO_(4) (density 1.787 g mL^(-1)) si labelled as 86% by weight. What is the molarity of acid? What volume of acid has to be used to make 1 L of 0.2 M H_(2) SO_(4) ?
Answer» Solution :` :.100 " g of " H_(2)SO_(4)`solution CONTAINS 86 g of `H_(2)SO_(4)` ` :. 100/(1.787)" mL " H_(2)SO_(4)`solution contains `86/98` mole . ` :.100 mL H_(2)SO_(4) ` solution contains `86/98 XX (1.787)/(100) xx1000` ` = 15.68 M ` ` :. " normality of "H_(2)SO_(4) = (2xx 15.68) N = 31.68 N ` ( basicity of `H_(2)SO_(4)=2`) SUPPOSE that V mLof `31.36 " N " H_(2)SO_(4)` is to usedto make 100 mL of` 0.2 M" (i.e ., 0.4 N )" H_(2)SO_(4)` ` :. ` m.e of v mL of `31.36 " N " H_(2)SO_(4) =` m.e of 1000mL of `0.4 " N " H_(2)SO_(4)` `31.36 xx v = 0.4 xx1000` ` v = (0.4 xx1000)/(31.36) = 12.75 mL `

Discussion

91218.	A bottle of dry ammonia and a bottle of dry hydrogen chloride connected through a long tube are opened simultaneously at both ends. The white ammonium chloride rind first formed will be
Answer» at the CENTRE of the TUBE near the hydrogenchloride BOTTLE near the AMMONIA bottle throughout the length of the tube Answer :B

Discussion

91219.	A bottle of commercial sulphuric acid (density = 1.787 g mL^(-1)) is labelled as 86 per cent by mass What is the molarity of the acid ? What volume of the acid has to be used to make 1 liotre of 0.2 M H_(2)SO_(4) ?
Answer» Solution :Step I. Calculation of molarity of the ACID solution. `"MASS of solution"=100 g, "Density of solution "=1.787"gm L"^(-1)` `"Volume of 100 g of solution"=("Mass")/("Density")=((100g))/((1.787" gm L"^(-1)))=55.9mL=0.0559 L.` `"Molarity of solution (M)"= ("Mass of" H_(2)SO_(4)//"Molar mass")/("Volume of solution in Litres")=((86g)//(98"g mol"^(-1)))/((0.0559L))` `=15.7" mol L"^(-1)=15.7 M.` Step II. `"Volume of "H_(2)SO_(4)"required".` `"Applying molarity equation," M_(1)V_(1)=M_(2)V_(2)` `(15.7 M)xxV_(1)=(0.2 M)xx(1L)` `V_(1)=((0.2M)xx(1L))/((15.7M))=0.0127xx1000=12.7 mL.`

Discussion

91220.	A bottle of cold drink contains 200ml liquid in which CO_(2) is 0.1 molar. Suppose CO_(2) behaves like an ideal gas, the volume of dissolved CO_(2) at S.T.P. is
Answer» 0.224L 0.448L 22.4L 2.24L Solution :MOLES of `CO_(2)` in 200mlof solution `= 200 xx 10^(-3) xx 0.1` `= 0.02 mol` SINCE `CO_(2)` BEHAVES as an ideal gas, 0.02mol of ` CO_(2)` will occupy `= 0.02 xx 22.4 L = 0.448 L`

Discussion

91221.	A bottle is heated with its mouth open from 15^(@)C to 100^(@)C. What fraction of air originally contained in the vessel is expelled ?
Answer» ANSWER :`23.5%`

Discussion

91222.	(A) Both phenol and phenoxide ion exhibit resonance, phenoxide ion is more stable than phenol(R) In phenoxide ion two equivalent resonating structures, and in phenol four equivalent resonating structures are present
Answer» Both (A) and (R) are true and (R) is the CORRECT EXPLANATION of (A) Both (A) and (R) are true and (R) is not the correct explanation of (A) (A) is true but (R) is FALSE Both (A) and (R) are false Answer :C

Discussion

91223.	(a) Both assertion and reason are correct and the reason is correct expansion to assertion. (b) Both assertion and reason are correct but reason is not the correct expansion of assertion (c) Assertion is correct but reasion is wrong (d) Assertion is incorrect but reason is correct. Q. Assertion: Phoverset(c+)(N)_2Br^(Theta) on reaction with nitrobenzene in the presence of NaOH gives p-nitro biphenyl. Reason: The reaction takes place by free radical mechanism.
Answer» SOLUTION :It is an EXAMPLE of gomberg REACTION which takes PLACE by FREE radical mechanism.

Discussion

91224.	Identify correct statement/s from the following: (a) Boron has the capacity to absorb neutrons. (b) Amorphous boron is used as a rocket fuel igniter. ( c ) Boron is essential for the cell walls of plants. (d) Boron shows reactivity at higher temperatures.
Answer» ANSWER :a, B and C

Discussion

91225.	A boron-hydrogen compound weighing 0.0553g created a pressure of 0.658 atm in a bulb of 40.7mL volume at 100^(@)C. Analysis showed it to be 85.7% boron. What is its molecular formula?
Answer» SOLUTION :`(B_(5)H_(9))`

Discussion

91226.	(A) Bond energy of Cl_(2) is less than that of F_(2) (R ) Bond energy of Br_(2) is less than that of F_(2)
Answer» Both (A) and (R ) are TRUE and (R ) is the correct EXPLANATION of (A) Both (A) and (R ) are true and (R ) is not the correct explanation of (A) (A) is true but (R ) is false Both (A) and (R ) are false ANSWER :D

Discussion

91227.	(a) Bond angle in PH_4 is higher than that in PH_3. Why ? (b) What is formed when PH_3 reacts with an acid ?
Answer» SOLUTION :(a) In `PH_3`, the presence of lone pair caused the l.p-b.p repulsions which results in decrease of bond angle where as in `PH_4^(+)` there are no I.p. of electrons and so MOLECULE experience only b.p-b.p repulsions. As Ip-b.p. repulsions are greater than b.p.-b.p. repulsions bond angle in `PH_(4)^(+)`is higher than `PH_(3)`. (b) With an acid, `PH_3` forms phosphonium SALT. For EXAMPLE, with HI, it forms phosphonium iodide `PH_(3) + HI to underset("Phosphonium iodide")(PH_(4)^(+))^(-)`

Discussion

91228.	(A) Boiling points of acids are higher than the corresponding alcohols. (R) Esters are hydrolysed with dilute mineral acids to give carboxylic acids.
Answer» Both (A) and (R) are true and (R) is the CORRECT EXPLANATION of (A) Both (A) and (R) are true and (R) is not the correct explanation of (A) (A) is true but (R) is false Both (A) and (R) are false Answer :B

Discussion

91229.	(A) Boiling point of NH_(3) is less than that of SbH_(3) (R ) In NH_(3) hydrogen bonding is observed.
Answer» Both (A) and (R ) are true and (R ) is the correct EXPLANATION of (A) Both (A) and (R ) are true and (R ) is not the correct explanation of (A) (A) is true but (R ) is FALSE Both (A) and (R ) are false Answer :2

Discussion

91230.	(A) Boiling point of helium is least(R) Intermolecular forces of attractions are almost absent in helium
Answer» Both (A) and (R) are TRUE and (R) is the correct EXPLANATION of (A) Both (A) and (R) are true and (R) is not the correct explanation of (A) (A) is true but (R) is false Both (A) and (R) are false Answer :A

Discussion

91231.	A : Boiling point of n-pentane is more than neopentane but the melting point of neopentane is more than n-pentane. R : Branching decreases the boiling point but increases the melting point.
Answer» If both Assertion & REASON are true and the reason is the correct explanation of the assertion, then mark (1). If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2) if Assertion is true statement but Reason is FALSE, then mark (3) If both Assertion and Reason are false statements, then mark (4) ANSWER :3

Discussion

91232.	A boiled egg show a/an_in entropy:
Answer» Increase Decreases No change None Answer :A

Discussion

91233.	(A) : Boiling a solution containing Cl^(-),Br^(-) and I^(-) with potassium persulphate, violet and brown vapours appear. (R ) : Br^(-) and I^(-) are oxidised to Br_(2) and I_(2) and Cl^(-) is not oxidised.
Answer» Solution :BENEDICT's solution copper- citrate complex `Cu^(2+)` ION is complexed as thus, is PREVENTED from precipitation as copper (II) HYDROXIDE.

Discussion

91234.	A 'body' which allows the short wavelength incoming solar radiation to enter in but does not allow long wave outgong infrared radiation to escape out is called :
Answer» GLOBAL warming Green house Atmospheric effect Ionosphere Answer :B

Discussion

91235.	A body of mass x kg is moving with a velocity of 100 m/s.Its de Broglie wavelength is 6.62xx10^(-35)m . Hencex is[h=6.2xx10^(-34)Js]
Answer» `0.25 kg` `0.15 kg` `0.2 kg` `0.1 kg` SOLUTION :`lamda=h/(MV)` `m=h/(lamdav)=(6.62xx10^(-34))/(6.62xx10^(-35)xx100)=0.1kg`

Discussion

91236.	A body of mass x g is moving with a velocity of 100m/s. It de Broglie wavelength is 6.62xx10^(-35)m. Hence x is (h=6.62xx10^(-34)J-s)
Answer» 0.25 kg 0.15 kg 0.2 kg 0.1 kg Solution :`lamda=h/(mv)` `6.62xx10^(-35)=(6.62xx10^(-34))/(x XX 100)` or `x=10^(-1)kg=0.1kg`

Discussion

91237.	A body of mass 10 mg is moving with a velocity of 100 ms^(-1).The wavelength of de-Brogile wave associated with it would be (h = 6.63 xx 10^(-34) Js)
Answer» `6.63 XX 10^(-35) m` `6.63 xx 10^(-34)` m `6.63 xx 10^(-31)` m `6.63 xx 10^(-37)` m Solution :`m = 10 mg = 10 xx 10^(-3) g` = `10 xx 10^(-6)` kg = `10^(-5)` kg `v = 100 ms^(-1)`, de Brogile, `lambda = ?` `h = 6.63 xx 10^(-34) Js^(-1)` de Brogile RELATION, `lambda = (h)/(mv)` `lambda = (6.63 xx 10^(-34)Js^(-1))/(10^(-5) xx 100) = (6.63 xx 10^(-34))/(10^(-3))` = `6.63 xx 10^(-31)` m.

Discussion

91238.	A body centred cubic lattice is made up of two elements A and B. Atoms of 'A' occupy two corners of the cube. If the remaining position in the cell are occupied by atoms of 'B'. Suggest the formula of the compounds.
Answer» SOLUTION :`AB_(7)`

Discussion

91239.	A body centred cubic element of density 10.3 "g cm"^3 has a cell edge of 314 pm. Calculate the atomic mass of element.
Answer» ANSWER : 96.03 GL

Discussion

91240.	A body centred cubic element of density, 10.3 g cm^(-3) has a cell edge of 314 pm. Calculate the atomic mass of the element. (N_A = 6.023 xx 10^(23) mol^(-1))
Answer» Solution :Z=2 for BEC structure , d = 10.3 G `cm^(-3)`, a = 314 pm , `N_A =6.023 xx 10^(23) mol^(-1)` `M = (N_A xx d xx a^3)/(Z)=(6.023 xx 10^(23) xx 10.3 xx (314)^3 xx 10^(-30))/(2) = 96 g mol^(-1)`

Discussion

91241.	A bluish green coloured compound 'A' on heating gives two products 'B' and 'C'. A metal 'D' is deposited on passing H_(2) through heated 'B'. The compound 'A' and 'B' are insoluble in water. 'B' is black in colour, dissolves in HCI and on treatment with K_(4)[Fe(CN)_(6)] gives a chocolate brown ppm of compound 'E'. 'C' is colourless, odourless gas and turns lime water milkly. The compounds 'D' and 'E' are respectively
Answer» `Cu, Cu_(2)[Fe(CN)_(6)]` `Fe, Cu_(2)[Fe(CN)_(6)]` `Cr, CuCO_(3)` Zn, CuO Solution :`underset(A)(CuCO_(3)) to underset("Black")(CuO)+underset(C)(CO_(2))` `CuO+H_(2) overset(Delta)to underset(D)(Cu)+H_(2)O` `CuO+2HCl to CuCl_(2)+H_(2)O` `2Cu^(2+)+K_(4)[Fe(CN)_(6)] to Cu_(2) underset(underset(E)("chacelate brown PPT"))([Fe(CN)_(6)]) darr`

Discussion

91242.	A bluish green coloured compound 'A' on heating gives two products 'B' and 'C'. A metal 'D' is deposited on passing H_(2) through heated 'B'. The compound 'A' and 'B' are insoluble in water. 'B' is black in colour, dissolves in HCI and on treatment with K_(4)[Fe(CN)_(6)] gives a chocolate brown ppm of compound 'E'. 'C' is colourless, odourless gas and turns lime water milkly. Compound 'A' is
Answer» `CuSO_(4)` `CuCO_(3)` `FeSO_(4)` `CrCl_(3)` Solution :`UNDERSET(A)(CuCO_(3)) to underset("Black")(CuO)+underset(C)(CO_(2))` `CuO+H_(2) overset(DELTA)to underset(D)(Cu)+H_(2)O` `CuO+2HCl to CuCl_(2)+H_(2)O` `2CU^(2+)+K_(4)[Fe(CN)_(6)] to Cu_(2) underset(underset(E)("chacelate brown ppt"))([Fe(CN)_(6)]) darr`

Discussion

91243.	A bluish green coloured compound 'A' on heating gives two products 'B' and 'C'. A metal 'D' is deposited on passing H_(2) through heated 'B'. The compound 'A' and 'B' are insoluble in water. 'B' is black in colour, dissolves in HCI and on treatment with K_(4)[Fe(CN)_(6)] gives a chocolate brown ppm of compound 'E'. 'C' is colourless, odourless gas and turns lime water milkly. The compounds 'B' and 'C' are respectively
Answer» `CuS, SO_(2)` CuO, `CO_(2)` FeO, `H_(2)S` `Cr_(2)O_(3), CO` Solution :`underset(A)(CuCO_(3)) to underset("Black")(CuO)+underset(C)(CO_(2))` `CuO+H_(2) overset(Delta)to underset(D)(Cu)+H_(2)O` `CuO+2HCl to CuCl_(2)+H_(2)O` `2Cu^(2+)+K_(4)[Fe(CN)_(6)] to Cu_(2) underset(underset(E)("chacelate brown ppt"))([Fe(CN)_(6)]) darr`

Discussion

91244.	A blue solution of copper sulphate becomes darker when treated with excess of ammonia. This is because
Answer» ammonia molecules REPLACE WATER molecules in the solution ammonia is stronger ligand than water ammonia froms a stable comlex ion `[Cu(NH_(3)_(4)]^(2+)`with Cu^(2+)` ions All of above Solution :`underset("BLUE")([Cu(H_(2)O)_(4)]^(2+))+SO_(4)^(2-)+4NH_(3)rarr[Cu(NH_(3))_(4)]^(2+)+4H_(2)O` `NH_(3)` being a stronger ligand than `H_(2)O`, replaces `H_(2)O` and forms stable deep-blue coloured complex with `Cu^(2+)`.

Discussion

91245.	A blue coloured residue obtained in cobalt nitrate charcoal cavity test is due to
Answer» `Zn^(2+)` `Mg^(2+)` `Sn^(2+)` `AL^(3+)` SOLUTION :`Al_(2)O_(3).CoO` formed in the test is blue in colour.

Discussion

91246.	A blue colouration is not obtained when
Answer» ammonium hydroxide dissolves in COPPER SULPHATE copper sulphate SOLUTION reacts with `K_(4)[Fe(CN)_(6]` Ferric chloride reacts with sod. FERROCYANIDE. anhydrous `CuSO_4` is dissolved in water. Solution :`2CuSO_(4) + K_(4)[Fe(CN)_6] rarr underset("Chocolate PPT")(Cu_2 [ Fe(CN)_6] + 2K_2SO_4)`

Discussion

91247.	A blue colouration is not obtained when :
Answer» Ammonium HYDROXIDE DISSOLVES in copper sulphate Copper sulphate solution REACTS with `K_4[Fe(CN)_6]` Ferric CHLORIDE reacts with sodium ferro-cyanide Anhydrous white `CuSO_4` is dissolved in water Answer :B

Discussion

91248.	A blown-up balloon has a volume of 500 mL at 5^@C . The balloon is distended to7/8 of its maximum stretching capacity. Will the balloon burst at 30^@C? Determine the minimum temperature above which it will burst.
Answer» SOLUTION :No , `44.7^@C`

Discussion

91249.	A blackish - brown solid (A) is oxidised in air with the hydroxide of an alkali metal. It produces a deep green compound (B) which on electrolytic oxidation in alkaline medium produces a deep green compound (B) which on electrolytic oxidation in alkaline medium produces a deep violet compound (C ). Identify A, B and C.
Answer» Solution :`A : MnO_(2), B : K_(2)MnO_(4), C : KMnO_(4)`

Discussion

91250.	(a) Blackish brown coloured solid (A) which is an oxide of manganese, when fused with alkali metal hydroxide and an oxidising agent like KNO_(3), produces a dark green coloured compound (B). Compound (B) on disporportionation in neutral and acidic solution gives a purple coloured compound (C). Identify (A), (B) and (C) and write the reaction involved when compound (C) is heated to 513 K. (b) (i) E^(@)_(M^(3+)//M^(2+)) values for the first series of transition elements are given below. Answer the question that follows. Identify the two strongest oxidising agents in the aqueous solution from the above data. (ii) Cu (I) ion in aqueous solution is not known (iii) The highest oxidation state of a metal is exhibited in its oxide.
Answer» Solution :(a) Compounds (A), (B) and (C) are `underset((A))(MnO_(2))``underset((B))(K_(2)MnO_(4))``underset((C))(KMnO_(4))` The reactions are explained as under `underset((A))underset(("Blackish brown"))underset("dioxide")underset("Manganese")(2MnO_(2))+4KOH+O_(2)tounderset((B))underset(("Dark green"))underset("manganate")underset("Potassium")(2K_(2)MnO_(4))+2H_(2)O` `underset((B))(3K_(2)MnO_(4))+4HCl to underset("PERMANGANATE")underset("Potassium")underset((C))(2KMnO_(4))+MnO_(2)+4KCl+2H_(2)O` `underset((C))underset("permanganate")underset("Potassium")(2KMnO_(4))underset(Delta)overset(513K)to underset("manganate")underset("Potassium")(K_(2)MnO_(4))+MnO_(2)+O_(2)` (b) (i) `Co(3+)` and `Mn^(3+)` are the strongest oxidising AGENTS because they have the highest positive values for `E_(M^(3+)//M^(2+))^(0)`. (ii) COPPER (I) ions are unstable in aqueous solutions and undergo disproportionation. `2Cu^(2+)to Cu^(2+)+Cu` (iii) Oxygen has a small size and a high electronegativity. Hence they can oxidise the METAL to high oxidation state by prompting all the valence electrons to participate in bonding.

Discussion

Explore topic-wise InterviewSolutions in .

A broad spectrum antibiotic is :

A bridging ligand possesses:

A bidentale ligand is

A brick red colour is imparted by a

(a) BrHC=CHBr exists as two diastereomers draw them and compare their dipole moment. (b) trans-Butenedioic acid has higher melting point than cis-butendioic acid. Why? (c) Draw the cis cand trans structure of hex-2-ene. Which isomer will have higher b.p. and why ?

A breaker contains a solution of substance 'A'. Precipitation of substance 'A' takes place when small amount of 'A' is added to the solution. The solution is ………….

A+Brarr"Product",(dx)/(dt)=k[A]^(a)[B]^(b) If ((dx)/(dt))=k, then order of reaction is :

A+BrarrCH_(3)-OC(CH_(3))_(3)overset(HI)rarrX+Y Correct statement among the following is

A box contains some identical red coloured balls, labelled as A, each weighing 2 grams. Another box contains identical blue coloured balls, labelled as B, each weighing 5 grams. Consider the combinations AB, AB_(2),A_(2)B and A_(2)B_(3) and show that law of multiple proportions is applicable.

A box contains 12xx10^(22) number of oxygen atoms. Find moles of O-atoms? (N_(A)=6xx10^(23))

A box is divided into two equal compartments by a thin partition and they are filled with gases P and Q respectively . The two compartments have a pressure of 250 torr each. The pressure after removing the partition will be equal to

A bottle, which contains 200 ml of 0.1KOH, absorbs 1 millimole of CO_(2) from the air, If the solution is then treated with standard acid using phenolphthalein indicator, the normally will be

A bottle of H_(3)PO_(4) solution contains 70% acid. If the density of the solution is 1.54 gcm^(-3) , the volumeof the H_(3)PO_(4) solution required to prepare 1L of IN solution is .

A bottle of milk stored at 300 K sours in 36 hours. When stored in a refrigerator at 275 K it sours in 360 hours, Calculate the energy of activation of the reaction involved in the souring process.

A bottle of dry NH_3 and bottle of dry HCl connected through a long tube are opened simultaneously at both ends, the white (NH_4Cl) ring first formed will be :

A sample of H_(2) SO_(4) (density 1.787 g mL^(-1)) si labelled as 86% by weight. What is the molarity of acid? What volume of acid has to be used to make 1 L of 0.2 M H_(2) SO_(4) ?

A bottle of dry ammonia and a bottle of dry hydrogen chloride connected through a long tube are opened simultaneously at both ends. The white ammonium chloride rind first formed will be

A bottle of commercial sulphuric acid (density = 1.787 g mL^(-1)) is labelled as 86 per cent by mass What is the molarity of the acid ? What volume of the acid has to be used to make 1 liotre of 0.2 M H_(2)SO_(4) ?

A bottle of cold drink contains 200ml liquid in which CO_(2) is 0.1 molar. Suppose CO_(2) behaves like an ideal gas, the volume of dissolved CO_(2) at S.T.P. is

A bottle is heated with its mouth open from 15^(@)C to 100^(@)C. What fraction of air originally contained in the vessel is expelled ?

(A) Both phenol and phenoxide ion exhibit resonance, phenoxide ion is more stable than phenol(R) In phenoxide ion two equivalent resonating structures, and in phenol four equivalent resonating structures are present

Identify correct statement/s from the following: (a) Boron has the capacity to absorb neutrons. (b) Amorphous boron is used as a rocket fuel igniter. ( c ) Boron is essential for the cell walls of plants. (d) Boron shows reactivity at higher temperatures.

A boron-hydrogen compound weighing 0.0553g created a pressure of 0.658 atm in a bulb of 40.7mL volume at 100^(@)C. Analysis showed it to be 85.7% boron. What is its molecular formula?

(A) Bond energy of Cl_(2) is less than that of F_(2) (R ) Bond energy of Br_(2) is less than that of F_(2)

(a) Bond angle in PH_4 is higher than that in PH_3. Why ? (b) What is formed when PH_3 reacts with an acid ?

(A) Boiling points of acids are higher than the corresponding alcohols. (R) Esters are hydrolysed with dilute mineral acids to give carboxylic acids.

(A) Boiling point of NH_(3) is less than that of SbH_(3) (R ) In NH_(3) hydrogen bonding is observed.

(A) Boiling point of helium is least(R) Intermolecular forces of attractions are almost absent in helium

A : Boiling point of n-pentane is more than neopentane but the melting point of neopentane is more than n-pentane. R : Branching decreases the boiling point but increases the melting point.

A boiled egg show a/an_in entropy:

(A) : Boiling a solution containing Cl^(-),Br^(-) and I^(-) with potassium persulphate, violet and brown vapours appear. (R ) : Br^(-) and I^(-) are oxidised to Br_(2) and I_(2) and Cl^(-) is not oxidised.

A 'body' which allows the short wavelength incoming solar radiation to enter in but does not allow long wave outgong infrared radiation to escape out is called :

A body of mass x kg is moving with a velocity of 100 m/s.Its de Broglie wavelength is 6.62xx10^(-35)m . Hencex is[h=6.2xx10^(-34)Js]

A body of mass x g is moving with a velocity of 100m/s. It de Broglie wavelength is 6.62xx10^(-35)m. Hence x is (h=6.62xx10^(-34)J-s)

A body of mass 10 mg is moving with a velocity of 100 ms^(-1).The wavelength of de-Brogile wave associated with it would be (h = 6.63 xx 10^(-34) Js)

A body centred cubic lattice is made up of two elements A and B. Atoms of 'A' occupy two corners of the cube. If the remaining position in the cell are occupied by atoms of 'B'. Suggest the formula of the compounds.

A body centred cubic element of density 10.3 "g cm"^3 has a cell edge of 314 pm. Calculate the atomic mass of element.

A body centred cubic element of density, 10.3 g cm^(-3) has a cell edge of 314 pm. Calculate the atomic mass of the element. (N_A = 6.023 xx 10^(23) mol^(-1))

A blue solution of copper sulphate becomes darker when treated with excess of ammonia. This is because

A blue coloured residue obtained in cobalt nitrate charcoal cavity test is due to

A blue colouration is not obtained when

A blue colouration is not obtained when :

A blown-up balloon has a volume of 500 mL at 5^@C . The balloon is distended to7/8 of its maximum stretching capacity. Will the balloon burst at 30^@C? Determine the minimum temperature above which it will burst.