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InterviewSolution
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.
| 401. |
Silicones are water repelling in nature because-A. they have highly covalent `Si-O-Si` linkages.B. they have organic groups forming hydrophobic exterior.C. they are polymoric in nature.D. they have `Si-H` bonds as in hydrocarbons. |
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Answer» Correct Answer - B |
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| 402. |
If the starting material for the manufacture of silicone is `RSiCl_(3)`, write the structure of the product formed. |
| Answer» Correct Answer - A::B::C::D | |
| 403. |
Amorphous boron is extracted from borax by the following steps : `"Borax" overset((A))rarr H_(3) BO_(3) overset("Heat")rarr B_(2) O_(3) overset((B)) rarr "Boron" (A) and (B) are` (a) `H_(2) SO_(4), Al` (b) `HCl`, Carbon ( c) `H_(2) SO_(4), Mg` (d) `HCl, Fe`.A. `H_(2)SO_(4),Al`B. `HCl`,carbonC. `H_(2)SO_(4),Mg`D. `HCl,Fe` |
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Answer» Correct Answer - C `Na_(2)B_(4)O_(7)+H_(2)SO_(4)+5H_(2)OtoNa_(2)SO_(4)+4H_(3)BO_(3)` `2H_(3)BO_(3)toB_(2)O_(3)+3H_(2)O` `B_(2)O_(3)+3Mg to 2B+3MgO` |
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| 404. |
Given type of silicones are called `[P]` `-O-oversetoverset(R)(|)underset(R)underset(|)(Si)-O-oversetoverset(R)(|)underset(R)underset(|)(Si)-O-oversetoverset(R)(|)underset(R)underset(|)(Si)-` `[P]` is prepared by hydrolysis of `[Q]` `[P]` & `[Q]` are respectively.A. Linear silicone, `CH_(3)SiCl_(3)`B. branched silicone, `(CH_(3))_(3)SiCl`C. Cyclic silicone, `(CH_(3))_(2)SiCl_(2)`D. Cyclic silicone, `CH_(3)SiCl_(3)` |
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Answer» Correct Answer - C `4(CH_(3))_(2)+8H_(2)Oto[P]+8HCl+4H_(2)O` |
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| 405. |
Define an alum. What are some of its important uses? |
| Answer» Correct Answer - A::B::C::D | |
| 406. |
`C Cl_(4)` is inert towards hydrolysis but `SiCl_(4)` is readily hydrolysed becauseA. carbon cannot expand its octet but silicon can expand its octetB. ionisation potential of carbon is higher than siliconC. carbon forms double and triple bondsD. electronegativity of carbon is higher than of silicon |
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Answer» Correct Answer - A `C Cl_(4)` is not readily hydrolysed due to non-availability of `d`-orbital in carbon. |
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| 407. |
The role of addition of `Me_(3)SiCl` during the hydrolysis followed by conduction of `Me_(3)SiCl_(2)` is.A. To catalyte the reaction.B. To terminate the chain and hence controlling the molecular weight.C. For obtaiming a proper cross linking.D. All of the above |
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Answer» Correct Answer - B Being containing one halogens atom it is ultilized for terminating the chain. |
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| 408. |
How many of the following may react with `SiCl_(4)` to produce a non-polar product ? `NaH, CH_(3)MgCl, H_(2)O, LiAlH_(4), H_(2)SO_(4)(l),NH_(3), Be` |
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Answer» Correct Answer - D `4NaH+SiCl_(4)to4NaCl+SiH_(4) uarr`(non-polar) `CH_(3)MgCl+SiCl_(4)toMgCl_(2)+Si(CH_(3))_(4)`(non-polar) `3H_(2)O+SiCl_(4)to H_(2)SiO_(3)+4HCl` `LiAiH_(4)+SiCl_(4)to LiCl + AlCl_(3)+SiH_(4)`(non-polar) `H_(2)SO_(4)(l)+SiCl_(4) to ` no reaction `NH_(3)+SiCl_(4) to ` Polymeric substance `2Be+SiCl_(4) to 2BeCl_(2)+Si`(non-polar) |
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| 409. |
Aqueous solution of potash alum is:A. alkalineB. acidicC. neutralD. soapy |
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Answer» Correct Answer - B It is acidic because of the hydrolysis of `Al_(2)(SO_(4))_(3)` according to the following reaction. `Al_(2)(SO_(4))_(3) + 6H_(2)O to 2Al(OH)_(3) + 3H_(2)SO_(4)` |
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| 410. |
Out of `C Cl_(4)` and `SiCl_(4)` which one reacts with water? |
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Answer» Correct Answer - Due to the presence of `d`-orbitals in `Si, SiCl_(4)` reacts with water but due to the absence of `d`-orbitals in `C,C Cl_(4)` does not react with `H_(2)O` |
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| 411. |
Which of a solution of sodium hydroxide is addeed in excess to the solution of potash alum, we obtainA. a white precipitateB. bluish white precipitateC. a clear solutionD. a crystalline mass |
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Answer» Correct Answer - C Potash alum is `K_(2)SO_(4).Al_(2)(SO_(4))_(3).24H_(2)O` and so, `Al_(2)(SO_(4))_(3)+6NaOHto 2Al(OH)_(3)darr ("white")+3Na_(2)SO_(4) , Al(OH)_(3)+OH^(-)to [Al(OH)_(4)]^(-)` (soluble complex) |
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| 412. |
Which silicon compound is used in machinary (with moving parts) in a manner similar to the use of an allotrops a covalent network solid and a molecular solid?A. Silica gelB. ZeoliteC. SiliconeD. Silane |
| Answer» Correct Answer - C | |
| 413. |
Name the element of group `13` which forms only covalent compounds. |
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Answer» Correct Answer - Because of small size and high sum of first three ionization enthalpies `(Delta_(i)H_(1)+Delta_(i)H_(2)+Delta_(i)H_(3)),B` forms only covalent compounds. |
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| 414. |
Give balance equation for the reaction of aluminium with aqueous sodium hydroxide. |
| Answer» Correct Answer - A::B::C | |
| 415. |
Why carbon froms covalent compounds whereas lead forms ionic compounds ? |
| Answer» Correct Answer - A::B::C::D | |
| 416. |
In silicon dioxide:A. there are double bonds between silicon and oxygen atoms.B. silicon atom is bonded to two oxygen atoms.C. each silicon atom is surrounded by two oxygen atoms and each oxygen atom is bonded to two silicon atoms.D. each silicon atom is surrounded by four oxygen atoms and each oxygen atom is bonded to two silicon atoms. |
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Answer» Correct Answer - D Silicon dioxide exhibits polymorphism.It is a network solid in which each `Si` atom is surrounded tetrahedrally by four oxygen atoms. `-O-undersetundersetunderset(|)(O)(|)oversetoversetoverset(|)(O)(|)(Si)-O-undersetundersetunderset(|)(O)(|)oversetoversetoverset(|)(O)(|)(Si)-O-` |
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| 417. |
Boron form covalent compound due toA. Higher ionization energyB. Lower ionization energyC. Small sizeD. Both (A) and ( C) |
| Answer» Correct Answer - D | |
| 418. |
Which of the following facts regarding boron and silicon in true?A. Boron is used to make boron steel or boron carbide control rods for nuclear reactor.B. Boron and silicon form halides which are not hydrolysed.C. Boron and silicon react with magnesium to form magnesium boride and magnesium silicide which are decomposed by acids to give volatile borane and silane, respectively.D. Both boron and silicon react with alkali to form borates and silicates containing `BO_(3)^(3-)` and `SIO_(4)^(4-)` tetrahedral units, respectively. |
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Answer» Correct Answer - A::B::D (B)`BCl_(3)+3H_(2)O overset("Hydrolysis")to H_(3)BO_(3) + 3HCl , SiCl_(4)+3H_(2)O overset("Hydrolysis")to H_(2)SiO_(3) + 4HCl` ( C)`B+Mg to Mg_(3)B_(2) +H_(3)PO_(4) to "Mix of borones" overset(Delta) to B_(2)H_(6)` (D)`2B+6NaOH to 2Na_(3)BO_(3) + 3H_(2) , Si+4NaOH to Na_(4)SiO_(4) + 2H_(2)` |
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| 419. |
Carbon and silicon belong to group `IV`. The maximum coordination number of carbon in commonly occuring compounds is four whereas that of silicon is six. This is due toA. Large size of siliconB. More electropositive nature of siliconC. Availability of low lying `d`-orbitals in siliconD. Both (A) and (B) |
| Answer» Correct Answer - C | |
| 420. |
From `B_(2)H_(6)`, all the following can be prepared exceptA. `H_(3)BO(3)`B. `[BH_(2)(NH_(3))_(2)]^(+) [BH_(4)]^(-)`C. `B_(2)(CH_(3))_(6)`D. `NaBH_(4)` |
| Answer» Correct Answer - C | |
| 421. |
`BCl_(3)` is trigonal planr while `AlCl_(3)` is tetrahedral in dimeric state. Explain. |
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Answer» Correct Answer - Both `BCl_(3)` and `AlCl_(3)` are electron deficient molecules having six electrons in the valence shell of their respective central atoms.To complete their octets, the central atom in each case can accept a pair of electrons from the chlorine atom of another molecule forming dimeric structures. However, because of small size of `B`,it cannot accommodate four big sized `Cl` atoms around it.Therefore, `BCl_(3)` prefers to exist as a monomeric planar molecule in which `B` atom is `sp^(2)-` hybridized. On the other hand, `Al` because of its bigger size can easily accommodate four `Cl` atoms around it.As a result, `AlCl_(3)` exists as a dimer, since the covalency of `Al` has increased to `4`.Therefore, `Al` is `sp^(3)`-hybridized and the four `Cl` atoms are held tetrahedrally around it. |
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| 422. |
All the boron trihalides except `BI_(3)` may be prepared by direction between the elements. Boron trihalides consist of trigonal-planar `BX_(3)` molecules. Unlike the halides of the other elements in the group they are monomeric in the gas, liquid and solid states, `BF_(3)` and `BCl_(3)` are gases, `BBr_(3)` is a volatile liquid and `BI_(3)` is a solid. Boron trihalides are Lewis acids because they form simple Lewis complexes with suitable bases, as in the reaction: `BF_(3)(g)+NH_(3)(g)toF_(3)B-NH_(3)(s)` However, boron chlorides, bromides and iodides are susceptible (sensitive) to protolysis by mild proton sources such as water, alcohols and even amines, for example `BCl_(3)` undergoes rapid hydrolysis: `BCl_(3)(g)+3H_(2)O(l)toB(OH)_(3)(aq)+3HCl (aq)` It is supposed that the first step in the above reaction is the formation of the complex `Cl_(3)B larr OH_(2)` which then eliminates `HCl` and reacts with water. Which is correct about the hydrolysis of `BX_(3)`?A. All `BX_(3)` undergo hydrolysis to produce `B(OH)_(3) (aq)` and `HX(aq)`.B. `BF_(3)` does not undergo complete hydrolysis due to formation of `HBF_(4)`C. `BBr_(3)` does not undergo hydrolysis at all because it cannot form `H`-bonds with water.D. All the above are correct |
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Answer» Correct Answer - B Some of the total `BF_(3)` combine with `HF` formed during hydrolysis to form `HBF_(4)`. |
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| 423. |
All the boron trihalides except `BI_(3)` may be prepared by direction between the elements. Boron trihalides consist of trigonal-planar `BX_(3)` molecules. Unlike the halides of the other elements in the group they are monomeric in the gas, liquid and solid states, `BF_(3)` and `BCl_(3)` are gases, `BBr_(3)` is a volatile liquid and `BI_(3)` is a solid. Boron trihalides are Lewis acids because they form simple Lewis complexes with suitable bases, as in the reaction: `BF_(3)(g)+NH_(3)(g)toF_(3)B-NH_(3)(s)` However, boron chlorides, bromides and iodides are susceptible (sensitive) to protolysis by mild proton sources such as water, alcohols and even amines, for example `BCl_(3)` undergoes rapid hydrolysis: `BCl_(3)(g)+3H_(2)O(l)toB(OH)_(3)(aq)+3HCl (aq)` It is supposed that the first step in the above reaction is the formation of the complex `Cl_(3)B larr OH_(2)` which then eliminates `HCl` and reacts with water. Which of the follwoing is the best order of Lewis acid strength of `BF_(3),BCl_(3)` and `BBr_(3)` ?A. `BF gt BCl_(3) gt BBr_(3)`B. `BF = BCl_(3) = BBr_(3)`C. `BF lt BCl_(3) lt BBr_(3)`D. `BBr_(3) lt BF_(3) lt BCl_(3)` |
| Answer» Correct Answer - C | |
| 424. |
The impurities like `As_(2)O_3` result in the poisoning of catalyst. In contact process, the impurities of arsenic are removed byA. gelantinuous `Fe(OH)_(3)`B. `Al(OH)_(3)`C. `Cr(OH)_(3)`D. `Fe_(2)O_(3)` |
| Answer» Correct Answer - A | |
| 425. |
Geometry of `IF_5` isA. linearB. trigonal planerC. Bent T-shapedD. Square pyramidal |
| Answer» Correct Answer - D | |
| 426. |
`O_3` is oxidising agentA. oxidising agentB. reducing agentC. both (A) and (B)D. none of these |
| Answer» Correct Answer - A | |
| 427. |
`PbO_(2)` is a stronger oxidising agent than `SnO_(2)`. Or `PbO_(2)` can act an oxidiside agent. |
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Answer» Correct Answer - In `PbO_(2)` and `SnO_(2)` both lead and tin present in `+4` oxidation state.But due to stronger inert pair effect,`Pb^(2+)` ion is more stable than `Sn^(2+)` ion. In other words, `Pb^(4+)` ions i.e. `PbO_(2)`, is more easily reduced to `Pb^(2+)` ions than `Sn^(4+)` ions are reduced to `Sn^(2+)` ions.Thus, `PbO_(2)` acts as a stronger oxidising agent than `SnO_(2)`. |
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| 428. |
Which of the following behaves as both oxidising and reducing agents ?A. `H_(2)SO_(4)`B. `SO_(2)`C. `H_(2)S`D. `HNO_(3)` |
| Answer» Correct Answer - B | |
| 429. |
Which of the following oxide is good oxidising agent?A. `O_(2)F_(2)`B. `OF_(2)`C. `ClO_(2)`D. `BrO_(2)` |
| Answer» Correct Answer - B | |
| 430. |
`H_2SO_4` act as oxidising agent withA. CB. `C_(6)H_(12)O_(6)`C. NaClD. NaOH |
| Answer» Correct Answer - A | |
| 431. |
Chlorine acts as a bleaching agent only in the presence ofA. dry airB. moistureC. sunlightD. pure oxygen |
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Answer» Correct Answer - B `Cl_2` gas reacts with `H_2O` to form HOCI and HCI. Hypochlorous and (HOCI) has bleaching action, because of its oxidising property. `HOCl to HCl +O` |
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| 432. |
Which compounds acts as an oxidising as well as reducing agent?A. `SO_(2)`B. `MgO_(2)`C. `Al_(2)O_(3)`D. `CrO_(3)` |
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Answer» Correct Answer - A The minimum and maximum oxidation number of S are -2 and +6 respectively. Since the oxidation number of S in `SO_(2)` is +4. therefore it can be either increased or decreased. Therefore `SO_(2)` behaves both as an oxidising as well as reducing agent. |
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| 433. |
Which of the following acts as pickling agent ?A. `HNO_(3)`B. `HCl`C. `H_(2)SO_(4)`D. `HNO_(2)` |
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Answer» Correct Answer - C To remove the oxide film on metallic sheet the sheet is dipped in `H_(2)SO_(4)` solution and them washed with water. This is known as pickling. `H_(2)SO_(4)` is used for cleansing metals before electroplateing, enamling, galvanising etc. |
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| 434. |
The hybrid orbital of the central atom in `AlF_(4)^(-)` is :A. `sp`B. `sp^(2)`C. `sp^(3)`D. `sp^(3)d` |
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Answer» Correct Answer - C |
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| 435. |
The number of lone pair of electrons in central atom of `CIF_5`A. OB. 1C. 2D. 3 |
| Answer» Correct Answer - B | |
| 436. |
(i)`P+C("carbon")+Cl_(2)toQ+CO uarr` , (ii)`Q+H_(2)OtoR+HCl` (iii)`BN+H_(2)O to R+NH_(3)` , (iv)`Q+LiAIH_(4) to S+LiCl+ AlCl_(3)` (v)`S+H_(2)toR+H_(2) uarr` , (vi)`S+NaH to T` (`P,Q,R,S` and `T` do not represent their chemical symbols) Compound S is: (I) an odd compound (II) (III) an electron deficient compound (IV) a hybridized compound Choose the correct code:A. IIIB. I,IIIC. II,III,IVD. I,II,IV |
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Answer» Correct Answer - A (i)`B_(2)O_(3)(P)+3C+3Cl_(2) to 2BCl_(3) (Q) +3CO uarr` (ii)`BCl_(3)(Q)+3H_(2)O to H_(3)BO_(3)(R)+3HCl` (iii)`BN+3H_(2)O to H_(3)BO_(3)(R ) + NH_(3)` (iv)`4BCl_(3)(Q)+3LiAlH_(4) to 2B_(2)H_(6)(S)+3LiCl+3AlCl_(3)` (v)`B_(2)H_(6)+6H_(2)O to 2H_(3)BO_(3) (R)+6H_(2) uarr` (vi)`B_(2)H_(6)(S)+2NaH to 2NaBH_(4)(T)` |
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| 437. |
The maximum covalency of nitrogen isA. 2B. 3C. 4D. 5 |
| Answer» Correct Answer - B | |
| 438. |
Which of following trihalides of nitrogen behaves as the weakest base?A. `NF_(3)`B. `NCl_(3)`C. `NBr_(3)`D. `NI_(3)` |
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Answer» Correct Answer - A Because of high electronegativity of F atom, the nitrogen atom attains positive charge and therefore, it has practically no electron-donating properties.. |
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| 439. |
The reddish-brown gas escaping on heating a chloride and `K_2Cr_2O_7` mixture with conc. `H2SO_4`A. `Cl_(2)`B. `CrO_(2)Cl_(2)`C. `CrO_(3)`D. `H_(2)CrO_(4)` |
| Answer» Correct Answer - B | |
| 440. |
First ever compound of a noble gas was prepared byA. Neil BartlettB. RamsayC. CavandishD. Faraday |
| Answer» Correct Answer - A | |
| 441. |
Noble gases are used in discharge tubes to give different colours. The gas in Beacon lights for pilots used is?A. ArB. NeC. XeD. Kr |
| Answer» Correct Answer - B | |
| 442. |
The noble gas which was discovered first in the sun and then on the earthA. heliumB. neonC. argonD. xenon |
| Answer» Correct Answer - A | |
| 443. |
The oxidation number of phosphorus in `Ba(H_(2)PO_(2))_(2)` is:-A. `+3`B. `+2`C. `+1`D. `-1` |
| Answer» Correct Answer - C | |
| 444. |
Which of the following statements is correct ?A. The major pollutant acids in acid rain are nitrous acid and sulphurous acidB. HF is a strong acid nboeC. `P_4O_6 and P_4O_10` are allotropes of phosphorusD. Phosphoric acid is a weak acid |
| Answer» Correct Answer - A | |
| 445. |
Which of the following compounds possess Lewis acid character ? (1) `BF_(3)` `BF_(3)` (2) `SiF_(4)` (3) `PF_(5)`A. 1 aloneB. 1,2, and 30C. 2 and 3D. 1 and 3 |
| Answer» Correct Answer - B | |
| 446. |
The product obtained on heating `NH_4NO_3` isA. `N_(2)O`B. `NO`C. `N_2O_(5)`D. `N_(2)O_(3)` |
| Answer» Correct Answer - A | |
| 447. |
Hydrogen bonding is strongest inA. O-H......SB. S-H.......OC. F-H.....FD. F-H.......O |
| Answer» Correct Answer - C | |
| 448. |
In the reaction `2Ag+2H_(2)SO_(4)rarrAg_(2)SO_(4)+2H_(2)O+SO_(2),H_(2)SO_(40`acts as `a//an` |
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Answer» Correct Answer - B `underset("Reducing agnet")(2Ag)+underset("Oxidising agent")(2H_(2)SO_(4))to Ag_(2)SO_(4)+2H_(2)O+SO_(2)` |
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| 449. |
Which of the following compounds is most acidic ?A. `H_(2)O`B. `H_(2)S`C. `H_(2)Se`D. `H_(2)Te` |
| Answer» Correct Answer - D | |
| 450. |
In `SF_4, S` atom is ........... hybridized.A. `sp^(3)`B. `sp^(3)d`C. `sp^(3)d^(2)`D. `dsp^(2)` |
| Answer» Correct Answer - B | |