Description : In \( III ^{ rd } \) group of salt analysis for cations \( NH _{4} Cl \) and \( NH _{4} OH \) are added as group reagents. Which of the following can be used instead of \( NH _{4} Cl \) ?(a) \( NaCl \)(b) \( \left( NH _ ... \)(c) \( \left( NH _{4}\right)_{2} C _{2} O _{4} \)(d) \( NH _{4} NO _{3} \)
Last Answer : In \( III ^{ rd } \) group of salt analysis for cations \( NH _{4} Cl \) and \( NH _{4} OH \) are added as ... O _{4} \) (d) \( NH _{4} NO _{3} \)
Description : 22. \( H _{2} O \) can act either as an acid or base. Which of the following reaction best illustrate the behaviour of water as a base?(a) \( H _{2} O + NH _{3} \rightarrow OH ^{+}+ NH _{4}^{-} \)(b) \( H _{ ... O \rightarrow H _{3} O ^{+}+ Cl ^{-} \)(d) \( HCl + NaOH \rightarrow NaCl + H _{2} O \)
Last Answer : 22. \( H _{2} O \) can act either as an acid or base. Which of the following reaction best illustrate ... HCl + NaOH \rightarrow NaCl + H _{2} O \)
Description : From the elements: Cl, Br, F, O, Al, C, Li, Cs and Xe; choose the following: (a) The element with highest negative electron gain enthalpy. (b) The element with lowest ionization enthalpy. ( ... . (f)The element which belongs to zero group. (g) The elements which forms largest number of compounds.
Last Answer : Ans. (a). The element chlorine (Cl) has the highest negative electron gain enthalpy. (b). The element cesium (Cs) has lowest ionization enthalpy. (c). The element fluorine F has lowest atomic radius. (d ... zero group (or group 18). (g). The element carbon (C) forms the largest number of compounds.
Description : 1 g of complex `[Cr(H_(2)O)_(5)Cl]Cl_(2).H_(2)O` was passed through a cation exchanger to produce HCl. The acid liberated was diluted to 1 litre. What
Last Answer : 1 g of complex `[Cr(H_(2)O)_(5)Cl]Cl_(2).H_(2)O` was passed through a cation ... molarity of acid solution [Molecular weight of complex=266.5]?
Description : Three different solutions of oxidising agents `KMnO_(4),K_(2)Cr_(2)O_(7) " and "I_(2)` is titrated separately with 0.158 gm of `Na_(2)S_(2)O_(3)`. If
Last Answer : Three different solutions of oxidising agents `KMnO_(4),K_(2)Cr_(2)O_(7) " and "I_(2)` is ... D. all three oxidising agent can act as self indicator.
Description : How many orders are correct: (a) H—F lt H-Cl lt H—Br lt H—I (Bond length) (b) H—F lt H—I ltH—Br ltH—I (Acidic strength) (C) H—I H—Br lt H—Cl ltH—F (Bo
Last Answer : How many orders are correct: (a) H-F lt H-Cl lt H-Br lt H-I (Bond length) (b) H-F lt H-I ltH- ... power) (f) H-Fgt H-Igt H-Brgt H-Cl (Boiling point)
Description : Arrange the following order of the property indicated: (a). F, Cl, Br and I (negative electron gain enthalpy) (b). Mg, Al, Si and Na (ionization enthalpy) (c). C, N, O and F (second ionization enthalpy)
Last Answer : Ans. (a). I
Description : In a `S_(N^(2))` substitution reaction of the type `R-Br+Cl^(-)overset("DMF")rarrR-Cl+Br^(-)` Which one of the following has the highest relative rate
Last Answer : In a `S_(N^(2))` substitution reaction of the type `R-Br+Cl^(-)overset("DMF")rarrR-Cl+Br^(-)` Which one of ... CH_(2)Br` D. `(CH_(3))_(2)CH-CH_(2)Br`
Description : Statement I: In strongly acidic solutions , anline becomes more reactive towards electrophilic reagents Statement II: The amino group being completely
Last Answer : Statement I: In strongly acidic solutions , anline becomes more reactive towards electrophilic reagents ... Assertion is false but Reason is true.
Description : Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH
Last Answer : Benzene + Br2/FeBr3
Description : Assertion: Phenol is more reactive than benzene towards electrophilic reactions. Reason : The +R effect of OH group increases the electron density on
Last Answer : Assertion: Phenol is more reactive than benzene towards electrophilic reactions. Reason : The +R effect of ... D. A is incorrect but R is correct
Description : Total number of stereoisomers of compound is: `CH_(3)-underset(overset(|)(OH))(C)H-underset(overset(|)(Br))(C)H-CH_(3)`
Last Answer : Total number of stereoisomers of compound is: `CH_(3)-underset(overset(|)(OH))(C)H-underset(overset(|)(Br))(C)H-CH_(3)` A. 2 B. 4 C. 6 D. 8
Description : Number of chiral carbon persent in the following compound: `CH_(3)-underset(overset(|)(OH))(C)H-CH_(2)-underset(overset(|)(Br))(C)H-underset(overset(|
Last Answer : Number of chiral carbon persent in the following compound: `CH_(3)-underset(overset(|)(OH))(C)H-CH_(2)-underset(overset( ... (3)` A. 2 B. 3 C. 4 D. 5
Description : Phosphates (e.g., tricresyl, tributyl, tetrabutyl, triphenyl etc.) are addedto polymers to act as (A) Hardeners (B) Anti-shrinkage agents (C) Plasticisers (D) Transparency improver
Last Answer : (C) Plasticisers
Description : Which one is the oxidising agent in the reaction given below `2CrO_(4)^(2-)+2H^(+)rarrCr_(2)O_(7)^(-2)+H_(2)O`
Last Answer : Which one is the oxidising agent in the reaction given below `2CrO_(4)^(2-)+2H^(+)rarrCr_(2)O_(7)^(-2)+H_(2)O` ... 2)O_(7)^(-2)` C. `Cr^(++)` D. None
Description : Asseration: `3SnCl_(2)+6HCl+O_(3)rarr3SnCl_(4)+3H_(2)O` is possible reaction showing oxidising nature of `O_(3)`. Reason: `O_(3)` whenever used as oxi
Last Answer : Asseration: `3SnCl_(2)+6HCl+O_(3)rarr3SnCl_(4)+3H_(2)O` is possible reaction showing oxidising ... as oxidising agent essentially liberates `O_(2)`.
Last Answer : Asseration: `3SnCl_(2)+6HCl+O_(3)rarr3SnCl_(4)+3H_(2)O` is possible reaction showing oxidising ... -I is not correct and Statement-II is correct
Description : (a) If the radius of the Br ion is 0.182 nm, how large a cation can fit in each of the tetrahedral hole. (b) AgI crystallizes in a cubic closed packed ZnS structure. What fraction of tetrahedral site ... Ag ion ? (c) At what temp. range, most of the metals becomes super conductors ?
Last Answer : (a) For a tetrahedron the limiting ratio is 0.225 – 0.414 For largest cation highest value 0.414 would be considered. r + / r– = 0.414 r + = 0.414 × 0.182 = 0.075 nm. (b) In FCC there are 8 tetrahedral voids. Out of this ½ is occupied by Ag cation. (c) 2 k – 5 k.
Description : Predict the products in the given reaction CHO Cl 50% KOH (1) OH OH OH O - O (2) OH Cl Cl O O - (3) OH OH OH OH (4) OH Cl Cl O - O Sol: [4] CHO Cl 50% KOH COOK Cl Cl OH
Last Answer : CHO Cl 50% KOH COOK Cl Cl OH
Description : The enthalpy changes at 298 K in successive breaking of `O-H` bonds of water, are `H_(2)O(g) rarr H(g)+OH(g),DeltaH=498kJ mol^(-1)` `OH(g) rarr H(g)+O
Last Answer : The enthalpy changes at 298 K in successive breaking of `O-H` bonds of water, are `H_(2)O(g) rarr H(g)+OH(g), ... KJ mol"^(-1)` D. `463 "KJ mol"^(-1)`
Description : `CH_(3)-CH_(2)-CH_(2)-underset(OH)underset(|)(CH)-CH_(3) underset(-H_(2)O)overset(H^(o+))rarr[F] overset(Br_(2)//C Cl_(4))rarrC_(5)H_(10)Br_(2)(G)` Ho
Last Answer : `CH_(3)-CH_(2)-CH_(2)-underset(OH)underset(|)(CH)-CH_(3) underset(-H_(2)O)overset(H^(o+))rarr[F] ... (including all stereoisomers) A. 2 B. 6 C. 3 D. 5
Description : Using the following thermochemical data. `C(S)+O_(2)(g)rarr CO_(2)(g), Delta H=94.0` Kcal `H_(2)(g)+1//2O_(2)(g)rarr H_(2)O(l), Delta H=-68.0` Kcal `C
Last Answer : Using the following thermochemical data. `C(S)+O_(2)(g)rarr CO_(2)(g), Delta H=94.0` Kcal `H_(2)(g)+1// ... .0` Kcal C. `-114.0` Kcal D. `+114.0` Kcal
Description : Given that - `2C(s)+2O_(2)(g)rarr 2CO_(2)(g) Delta H = -787 KJ` `H_(2)(g)+ 1//2O_(2)(g)rarr H_(2)O(l) Delta =-286 KJ` `C_(2)H_(2)(g)+(5)/(2)O_(2)(g)ra
Last Answer : Given that - `2C(s)+2O_(2)(g)rarr 2CO_(2)(g) Delta H = -787 KJ` `H_(2)(g)+ 1//2O_(2)(g)rarr H_(2) ... 1802` KJ B. `-1802` KJ C. `-800` KJ D. `+237` KJ
Description : `4M(s)+overset(Ө)(C)N(aq.)+2H_(2)O(aq.)+O_(2)(g)` `" " to 4[M(CN)_(2)]^(Ө)(aq.)+4overset(Ө)(O)H(aq.)
Last Answer : `4M(s)+overset(Ө)(C)N(aq.)+2H_(2)O(aq.)+O_(2)(g)` `" " to 4[M(CN)_(2)]^(Ө)(aq.)+4overset(Ө)(O)H(aq.) A ... 2)` D. `[Ag(CN)_(2)]^(-),[Zn(CN)_(4)]^(-2)`
Description : Assertion (A): UV radiation causes photodissociation of ozone into `O_(2)` and O, thus causing damage to the stratospheric change. Reason (R): Ozone h
Last Answer : Assertion (A): UV radiation causes photodissociation of ozone into `O_(2)` and O, thus causing damage ... true but reason is wrong D. Both are wrong
Description : What is the coordination number of an ion what is the coordination number of the cation (a) Na Cl structure and (b) Cs Cl structure explain the reason for this difference?
Last Answer : The coordination number is six for Na in NaCl.The coordination number is eight for Cs in CsCl. The accepted explanation is that the ionic radii of cesium and chloride are very similar.
Description : `K_2S_2O_8` , acidic `K_2S_2O_8` and acidic `MnO_2` oxidise `I^(-), Br^(-) , Cl^(-)` to `I_2 , Br_2 and Cl_2` , respectively. From the given data the
Last Answer : `K_2S_2O_8` , acidic `K_2S_2O_8` and acidic `MnO_2` oxidise `I^(-), Br^(-) , Cl^(-)` to `I_2 , ... gt I_2 gt Br_2` D. `Cl_2 gt K_2 S_2O_8 gt Br_2`
Description : For the following `(i) I^(-) (ii) Cl^(-) (iii) Br^(-)` the increasing order of nucleophilicity would be:
Last Answer : For the following `(i) I^(-) (ii) Cl^(-) (iii) Br^(-)` the increasing order of nucleophilicity would be: A. ... )ltCl^(-)` D. `Cl^(-)ltBr^(-)ltI^(-)`
Description : Which has the smallest bond angle `X-S-X` in the given molecules ? (X=F, Cl, Br, I)
Last Answer : Which has the smallest bond angle `X-S-X` in the given molecules ? (X=F, Cl, Br, I) A. `SOF_(2)` B. `SOC1_(2)` C. `SOBr_(2)` D. `SOI_(2)`
Description : The increasing order of reactivity among group 1 elements is Li
Last Answer : Ans. In group 1 elements (alkali metals) the reactivity of the metals is mainly due to the electron releasing tendency of their atoms, which is related to ionization enthalpy, Since ... electron gain enthalpy. Since both of them decrease down the group, the reactivity therefore decreases.
Description : Which of the following is the strongest nucleophile in an aqueous solution? (a) HO– (b) Cl– (c) Br– (d) I
Last Answer : I–
Description : Which of the following is the best leaving group? (a) F– (b) Cl– (c) Br– (d) I–
Description : The halogen with the largest atomic radius is: w) Cl x) I y) Br z) At
Last Answer : ANSWER: Z -- At
Description : How an — OH group attached to carbon in the benzene ring activates benzene towards electrophilic substitution ?
Last Answer : The lone pair of electrons present on oxygen atom enter into resonance with the benzene ring. As a result, the electron density becomes higher at o- and p- position and due to higher electron density, the ring gets activated towards electrophilic substitution.
Description : Electron are emitted from an electron gun at almost zero velocity and are accelerated by an electric field `E` through a distance of `1.0m` The electr
Last Answer : Electron are emitted from an electron gun at almost zero velocity and are accelerated by an electric field ... .5 nm` may be emitted by the hydrogen?
Description : Oxidising agents have high :-
Last Answer : Oxidising agents have high :- A. Reduction potential B. Oxidation potential C. Ionisation potential D. None of these
Description : Determine the equivalent weight of the following oxidising and reducing agents : (a) `KMnO_(4)` (reacting in acidic medium `MnO_(4)^(-)rarrMn^(2+)`) (
Last Answer : Determine the equivalent weight of the following oxidising and reducing agents : (a) `KMnO_(4)` (reacting in ... medium `MnO_(4)^(-)rarr MnO_(2)`)
Description : In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents are
Last Answer : In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents are ... D. `HNO_(3) and CO` respectively
Last Answer : In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents are ... D. `HNO_(3)` and CO respectively
Description : What are Aldehydes? (1) Mild oxidising agents (2) Strong oxidising agents (3) Strong reducing agents (4) Mild reducing agents
Last Answer : (3) Strong reducing agents Explanation: Aldehydes are organic chemical compounds that include a-carbonyl group (i.e. an oxygen atom attached to a carbon atom by a double covalent bond) and a ... atom makes aldehydes very easy to oxidize. Or, put another way, they are strong reducing agents.
Description : Substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected are called - (1) Catalysts (2) Hydrocarbons (3) Oxidising agents (4) Substitutes
Last Answer : (1) Catalysts Explanation: Catalysts are substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected. Eg: hydrogenation of vegetable oils using a nickel catalyst.
Last Answer : Strong reducing agents
Description : Which of the following reagents will replace –OH group by a halogen atom? (a) HOCl (b) Br2 (c) SOCl2 (d) I2
Last Answer : SOCl2
Description : Among the complex ions, `[Co(NH_(2) - CH_(2) - CH_(2) - NH_(2))_(2) Cl_(2)]^(+), [CrCl_(2) (C_(2)O_(4))_(2)]^(3-)` `[Fe(H_(2)O)_(4) (OH)_(2)]^(+), [Fe
Last Answer : Among the complex ions, `[Co(NH_(2) - CH_(2) - CH_(2) - NH_(2))_(2) Cl_(2)]^(+), [CrCl_(2) ... (3)) Cl]^(2+)` and that show(s) cis-trans isomerism is
Description : In the process of extraction of gold. Roasted gold ore `+CN^(-)+H_(2)O overset(O_(2))rarr [X]+OH^(-)` `[X]+Znrarr [Y]+Au` Identify the complexes `[X]
Last Answer : In the process of extraction of gold. Roasted gold ore `+CN^(-)+H_(2)O overset(O_(2))rarr [X]+OH^(-)` `[X]+ ... (4)]^(-),[Y] =[Zn (CN_(4))]^(-2)`
Description : The end product (B) of the reaction sequence: `C_(2)H_(5)-underset(H)underset(|)(N)-CH_(3) overset(Ph-overset(O)overset(||)(C)-Cl)underset(NaOH)rarrA
Last Answer : The end product (B) of the reaction sequence: `C_(2)H_(5)-underset(H)underset(|)(N)-CH_(3) overset(Ph-overset ... )underset(H_(2)O)rarr B` A. B. C. D.
Description : Arrange the following in the decreasing order of Vander Waal’s radii: Cl, H, O, N.
Last Answer : Ans.The overall decreasing order is: Cl> N > O >H.
Description : What is the oxidation number of Cl in HClO (read: H - C - L - O)?
Last Answer : ANSWER: 1+ (accept 1)
Description : Extra departmental agents are employed to work as a) Delivery agents, in cases where full time postman are not justified b) Mail carriers in cases where departmental runner are not justified c) Stamp vendors & Chowkidars d) All the above
Last Answer : d) All the above
Description : When `KMnO_(4)` acts as an oxidising agnet and ultimetely from `MnO_(4)^(2-), MnO_(2), Mn_(2)O_(3)`, and `Mn^(2+)`, then the number of electrons trans
Last Answer : When `KMnO_(4)` acts as an oxidising agnet and ultimetely from `MnO_(4)^(2-), MnO_(2), Mn_(2)O_(3)`, and `Mn^(2+) ... 3, 7 C. 1, 3, 4, 5 D. 3, 5, 7, 1