This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 87401. |
A solid is made of two elements X and Z. The atoms Z are in C.C.P. arrangement while atoms X occupy all the tetrahedral sites. What is the formula of the compound- |
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Answer» XZ |
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| 87402. |
A solid is formed by two elements P and Q. The element Q forms cubic close packing and atoms of P occupy two-third of tetrahedral voids. The formula of the compound is |
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Answer» `PQ_(3)` No. of tetrahedral VOIDS = 2N No. of P atoms `=2n XX ( 1)/( 3)= ( 2n )/( 3)` FORMULA `: P : Q ` `( 2n )/( 3) : n ` or `2:3 ` `:. P _(2) Q_(3)` |
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| 87403. |
A solid is formed and it has three types of atoms X, Y, Z. X forms an FCC lattice with Y atoms occupying one-fourth of tetrahedral voids and Z atoms occupying half of the octahedral voids. The formula of the solid is |
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Answer» `X_4 Y_4 Z_2` |
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| 87404. |
A solid having no definite geometrical shape with flat faces and sharp edges is : |
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Answer» AMORPHOUS solid |
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| 87405. |
A solid has a structure in which "W" atoms are located at the corner of the cubic lattice "O" atoms at the centre of edge and Na atom at the centre of cube. The formula of the compound is ........... |
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Answer» `NaWO_2` Number of Na atoms = 1 Number of O atoms `= (12 xx 1/4) = 3` `THEREFORE Na : W : O = 1 : 1 : 3 implies NaWO_3`. |
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| 87406. |
A solid has a strcture in which 'W' atoms are located at the corners of a cubic lattice 'O' atoms at the centre of edges and 'Na' atoms at the centre of the cube. The formula for the compound is |
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Answer» `NaWO_(2)` O atoms at the centre of edges `=(1)/(4)xx12=3` Na atoms at the centre of the cube=1 `W:O:Na=1:3:1`, hence formula =`NaWO_(3)` |
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| 87407. |
A solid having density of 9 xx 10^3 "kg m"^(-3) form face centred cubic crystals of edge length 200sqrt(2) pm. What is the molar mass of solid ? (Avogadro's constant = 6 xx 10^23 "mol"^(-1), pi = 3) |
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Answer» `0.0216 "kg MOL"^(-1)` `THEREFORE 9 xx 10^3 = (4 xx M)/((200 sqrt(2))^3 xx 10^(-36) xx 6 xx 10^(23))` `therefore M = 0.0305 "kg mol"^(-1)`. |
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| 87408. |
A solid has a structure in which W atoms are located at the corners of the cubic lattice, O atoms at the centre of the edges and Na atom at the centre of the cube. The formula of the compound is |
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Answer» `NawO_(2)` |
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| 87409. |
A solid has a bcc structure. If the distance of closest approach between the two atoms is 1.73overset@A.The edge length of the cell is : |
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Answer» 200 pm142.2 pm |
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| 87410. |
A solid has a b.c.c. structure . If the distance of closest approach between the two atoms is 1.73 Å. The edge length of the cell is : |
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Answer» 199 PM |
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| 87411. |
A solid element burns in oxygen without any change in volume (of gas) under similar conditions of temperature and pressure. If the vapour density of pure gaseous product is 32, what is the equivalent mass of the element? |
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Answer» SOLUTION :One vol. of oxide contains 1 VOLT. Of `O_(2)`. One MOLE of oxide contains one mole of `O_(2)`. Mol. Mass of oxide `=A=32=2V.D.=64` 32 PARTS of element combine with 32 parts of oxygen. So, equivalent mass of element`=(32)/(32)xx8=8` |
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| 87412. |
A solid dissolves in water exothermically, if its saturated solution at 20^@C is cooled to 0^@C then:- |
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Answer» Some solid separates out |
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| 87413. |
A solid crystal is composed of X, Y and Z atoms. Y atoms are occupying 50% of octahedral voids, whereas X atoms are occupying the 100 % tetrahedral void with Z atoms in ccp array arrangement, then the number of Y atoms in rational formula the given cell. |
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Answer» |
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| 87414. |
A solid cube of edge length =25.32 mm of an ionic compound which has NaCl type lattice is added to 1kg of water.The boiling point of this solution is found to be 100.52^@C(assume 100% ionisation of ionic compound).If radius of anion of ionic solid is 200 pm then calculate radius of cation of solid in pm (picometer). (K_b of water =0.52 K kg "mole"^(-1),Avogadro's number,N_A=6xx10^(23),(root3(75))=4.22) |
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Answer» Hence, number of moles of IONIC solid in GIVEN cube=0.5 So, number of formula units in given cube `=0.5xx6xx10^(23)` Number of units cells `=1/4xx0.5xx6xx10^23=7.5xx10^22` number of unit cells along ONE edge of cube `=root(3)(75)xx10^7=4.22xx10^7` edge length of unit cell =`a=(25.32xx10^(-3))/(4.22xx10^7)m=600xx10^(-12) m =600` pm forNaCl type unit cell, `a=2(r_(+)+r_(-)) " " IMPLIES " " r_(+)=100` pm |
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| 87415. |
A solid compound XY has NaCl structure . If the radius of the cation is 100 pm , the radius of the anion will be …….. |
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Answer» `((100)/(0.414))` For an FCC structure `(r_(X))/(r_(Y)) = 0.414` , gives that `r_(X) = 100` PM `r_(Y) = (100 "pm")/(0.414)` |
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| 87416. |
A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion will be……………… |
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Answer» `((100)/(0.414))` GIVEN that `r_(X^(+))="100 PM "r_(y^(-))=("100 pm")/(0.414)` |
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| 87417. |
A solid compound 'X' on heating gives CO_(2) gas and a residue. The residue mixed with water forms 'Y'. On passing an excess of CO_(2) through Y in water, a clear solution 'Z' is obtained. On boiling 'Z' compound 'X' is formed. The compound 'X' is |
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Answer» `CaCO_(3)` |
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| 87418. |
A solid compound contains X,Y and Z atoms in a cubic lattice with X atoms occupying the corners. Y atoms in the body centered positions and Z atoms at the centres of faces of the unit cell. What is the empirical formula of the compound. |
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Answer» `XY_(2)Z_(1)` Atoms of Y per unit cell `=1` Atoms of Z per unit cell `=6xx(1)/(2)=3` Hence the formula is `XYZ_(3)`. |
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| 87419. |
Asolid compound contains XYZ atoms in a cubic lattice with X atoms occupying the corners, Y atomsin the body centred positions and Z atoms at the centres of faces of the unit cell. What is the empirical formula of the compound |
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Answer» |
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| 87420. |
A solid catalyst is more effective in its finely divided form - Justify. |
| Answer» SOLUTION :Finely divided FORM of a catalyst has GREATER surface area when compared to their crystalline form. Greater the surface area, greater the ADSORPTION and HIGHER the catalytical activity. | |
| 87421. |
A solid AB has ZnS-type structure. The edge lenth of unit cell is 400 pm abd the radius of B^- ion is 0.130 nm. Then the radius of A^+ ion is |
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Answer» 35.8 pm |
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| 87422. |
A solid AB has the NaCl structure. If the radius of the cation A^(+) is 150 pm, calculate the maximum possible value of the radius of the anion B^(-). |
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Answer» `:. r^(+) = 150` PM and for MAXIMUM value of `r^(-), (r^(+))/(r^(-)) = 0.414` `:. (150)/(r^(-))= 0.414` or `r^(-) =(150)/(0.414) = 362.3` pm |
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| 87423. |
A solid AB has rock salt structure. If the radius of cation is 100 pm, the maximum radius of anion B^(ө)is ........... |
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Answer» 120.7 PM |
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| 87424. |
A solid AB has NaCl structure. If the radius of cation A^(+) is 160 pm, calculate the maximum possible value of radius of the anion B^(-)? |
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Answer» Solution :The RADIUS ratio of `A^(+)` and `B^(-)` having `Na^(+)Cl^(-)` structure is = 0.414 to 0.732 `:. ("Radius of cation, "A^(+))/("Radius of anion, "B^(-))` = 0.414 to 0.732 `:. "Radius of anion "B^(-)=("Radius of cation, "A^(+))/("0.414 to 0.732") = (160)/("0.414 to 0.732")` = 386.47 to 218.58 PM `:.` Maximum POSSIBLE value of the radius of the anion `B^(-) = 386.47` pm |
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| 87425. |
A solid (A) which has photographic effect reacts with the solution of a sodium salt (B) to give a pale yellow ppt. (C). Sodium salt on heating gives brown vapour. Identify A, B and C |
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Answer» `AgNO_(3),NaBr,AgBr` |
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| 87426. |
Asolid A^+B^-has the B^-ions arranged as below .If the A^+ ions occupy half of the tetrahedral sites in the structure. The formula of solid is : |
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Answer» AB |
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| 87427. |
A sol of egg albumin can be coagulated by addition of : |
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Answer» ELECTROLYTES |
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| 87428. |
A sol may be prepared by a precipitation reaction. Give one such example. How can we find the nature of electric charge on the sol particles ? |
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Answer» Solution :`As_2S_3` SOL MAY be prepared by precipitation reaction as per the following reaction : `As_2O_3 + 3H_2S to As_2S_3 + 3H_2O` We can FIND the nature of charge on colloidal solution by electrophoresis. The colloidal PARTICLES move towards the oppositely charged electrode in an electric field. For example, the colloidal solution of `As_2O_3` is negatively charged and moves towards positive electrode. |
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| 87429. |
A soild, A which has photographic effect reacts with the solution of a sodium salt B to give a pale yellow precipitate C. Sodium salt on heatinggives brown vapours. Identity A,B and C. |
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Answer» `AgNO_(3),NaBr,AgBr` `underset(A)(AgNO_(3))+underset(B)(NaBr)rarrunderset(underset("Light yellow ppt.")(C))(AgBr+NaNO_(3))` |
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| 87430. |
A sodium salt X of an unknown anion when treated with MgCl_(2) gives precipate Y only on boiling. It gives lime water test positive but doesn't gives KMnO_(4) test. Compound X and Y can't be seperated by using. |
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Answer» Phenolphtalein TEST |
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| 87431. |
A sodium salt on treatment with MgCl_2 gives white precipitate only on heating. The anion of sodium salt is: |
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Answer» `HCO_3^(-) ` `Mg(HCO_3)_2 overset("HEAT")to MgCO_3 + H_2O + CO_2 UARR ` |
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| 87432. |
A sodium salt on treatment with MgCl_(2) gives white precipitate only on heating. The anion of sodium salt is |
| Answer» Solution :N//A | |
| 87433. |
A sodium salt (A) when reacts with dilute HCI produces a salt and a colouless, rotten egg smelling gas (B). (B) when passed through lead acetate solution produces a black precipitate (C). Futher (C) on treatment with H_(2) O_(2) solution yields a white precipitate (D). Identify (A). |
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Answer» `H_(2) S` `underset((A))(Na_2S)+ 2HCL to 2NaCl + underset((B))(H_2S)` `Pb(CH_3COO)_(2) + H_2S to underset(("BLACK PPT."))underset((C))(PbS darr) + 2CH_3COOH` `PbS + 4H_2O_2 to underset(("WHITE ppt."))underset((D))(PbSO_4) darr + 4H_2O` . |
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| 87434. |
A sodium salt of an unknown anionwhentreates with MgCI_(2)gives whiteprecipitate onlyon boling .The anion is |
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Answer» `SO_(4)^(2-)` `MgCI_(2) + 2NaHCO_(3) RARR underset("soluble")((Mg(HCO_(3))_(2)) + 2NaCI` `Mg(HCO_(3))_(2) OVERSET(Delta)(to) underset(white)(MgCO_(3) darr) + H_(2)o + co_(2)` |
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| 87435. |
(a) Sodium metal crystallizes in bcc structure. Its unit cell edge length is 420 pm. Calculate its density. (Atomic mass of sodium = 23 u, N_(A) = 6.022 xx 10^(23) mol^(-)). (b) What is Frenkel defect ? How does it affect the density of a crystal ? |
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Answer» Solution :(a) Density `= (Z.M)/(a^(2) N_(A))` `= (2 XX 23 xx 10^(-3))/(420 xx 10^(-12) xx 6.022 xx 10^(23))` `= 1.031 xx 10^(3) kg//m^(3)` (b) This is a defect caused by the DISLOCATION of a smaller ION from its normal site to an intersitial site. Density does not change. |
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| 87436. |
(A) Sodium can't be used for drying ethyl alcohol.(R) Sodium displaces hydrogen from ethyl alcohol. |
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Answer» Both A & Rare true, R is the correct EXPLANATION of A |
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| 87437. |
A + SOCl_2 to B + SO_2 + HCl X + Na to C + H_2B + C to (C_2H_5)_2O+ NaClThen A and X are respectively |
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Answer» ` C_2H_5CI and C_2H_5ONa` |
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| 87438. |
A soap can be obtained by the saponificattion of |
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Answer» Liquid paraffin |
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| 87439. |
(A) SO_(2) gas is easily liquified while H_(2) isdifficult to liquify . (R ) SO_(2) has low critical temperature while H_(2) has high critical temperature. |
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Answer» Both (A) and (R) are true and (R) is the correct explanation of (A) |
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| 87440. |
(A): SO_(3) molecule has a planar structure (R) : S atom in SO_(3) is sp^(2)- hybridized and O-S-O bond angle is 120^(@) |
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Answer» Both (A) and (R ) are TRUE and (R ) is the CORRECT EXPLANATION of (A) |
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| 87441. |
(A) SO _(2) acts as good reducing agent in aqueous solutions (R ) SO _(2) + 2 H _(O to H _(2) SO _(4) + 2 (H) |
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Answer» Both (A) and (R ) are TRUE and (R ) is the CORRECT EXPLANATION of (A) |
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| 87442. |
(A) SO _(2) is reducing agent and TeO _(2) is oxidising agent (R )From SO _(2) to TeO _(2) acidic nature of dioxides increases. |
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Answer» Both (A) and (R ) are true and (R ) is the correct EXPLANATION of (A) |
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| 87443. |
(A) SO _(2) is angular molecule (R ) In SO _(2) sulphur exhibit SP ^(2) hybridisation |
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Answer» Both (A) and (R ) are true and (R ) is the correct explanation of (A) |
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| 87444. |
(A) SnCl_(4) is more covalent than SnCl_(2) (R ) Compound with higher oxidation state of metal is more covalent than with lower oxidation state |
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Answer» Both (A) and (R ) are true and (R ) is the correct EXPLANATION of (A) |
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| 87445. |
(A) S_N2 reactions are exothermic (R) S_N2 reactions are thermochemically favored by stronger nucleophiles |
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Answer» Both (A) and (R) are correct and (R) is the correct EXPLANATION of (A) |
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| 87446. |
(A): S_(N^(2)) reaction takes place in single step.(R): S_(N^(2)) reaction involves the reactivity order of alkyl halides as 1^@ gt 2^@ gt 3^@ halides. |
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Answer» Both A & R are TRUE, R is the correct explanation of A |
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| 87447. |
A smuggler could not carry gold by depositing iron on gold surface since |
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Answer» gold has higher standard reduction potential than iron |
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| 87448. |
A smuggler could not carry gold by depositing iron on the gold surface since |
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Answer» Gold is denser |
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| 87449. |
A small sample of Uranium metal (0.119 gm) is heated to 900^(@) C in air to give 0.135 gm of a dark oxide, U_(x) O_(y). Then [U = 238] |
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Answer» Moles of `U_(X) O_(y)` formed `= 5 xx 10^(-3)` Moles of `U = (0.119)/(238) = 0.5 xx 10^(-3) = 5 xx 10^(-4)` Mass of oxygen in oxide `= (0.135 - 0.119)` `= 0.016 gm` Moles of oxgyen ATOM in oxide `= (0.016)/(16) = 1 xx 10^(-3)` `{:(U,,O,),(5 xx 10^(-4),,1 xx 10^(-3),),(0.5,:,1,),(1,:,2,):}` Emprical formula `= UO_(2)` |
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| 87450. |
A small iodine crystal is added to each of the following aq solutions: I. sodium sulphate II. Sodiumthiosulphate III. Sodium tetrathionate IV. Sulphuric acid In which solutions the purple colour disappers |
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Answer» only in I |
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