94420 + Interview Questions in Chemistry in Class 12

1.	Net work done by a system is given by:
Answer» Decrease in Helmholtz FREE energy `(triangleA)` Decrease in GIBB's free energy `(TRIANGLEG)` Decrease in internal energy Decrease in heat enthalpy Answer :A

Discussion

2.	Nessler's reagent is used to detect the presence of:
Answer» `CrO_(4)^(2-)` `PO_(4)^(3-)` `MnO_(4)^(-)` `NH_(4)^(+)` ANSWER :D

Discussion

3.	Nessler's reagent is
Answer» `K_2Hgl_4` in EXCESS of KI. `K_2 Hgl_4` in excess of KOH `K_2Hgl_4` in excess of HCI `Hgl_2` in excess of KOH Answer :B

Discussion

4.	Nessler's reagent used to test the presence of ammonia or NH_(4)^(+) is
Answer» `K_(2)HgI_(4)" in excess KI"` `K_(2)HgI_(4) " in excess KOH"` `K_(2)HgI_(4)" in excess HCL"` `H_(2)I_(2)" in excess KOH"` ANSWER :B

Discussion

5.	Nessler's reagent is used to detect
Answer» `CrO_(4)^(2-)` `PO_(4)^(3-)` `MnO_(4)^(-)` `NH_(4)^(+)` Solution :Nessler's REAGENT gives red PRECIPITATE with `NH_(4)^(+)` `NH_(4)Cl+2K_(2)[HgI_(4)]+4KOHtounderset("Iodide of Millon's base (BROWN ppt)")(NH_(2)-HG-O-HG-I)+7KI+KCl+3H_(2)O`

Discussion

6.	Nesseler's reagent is:-
Answer» `K_(2)HgI_(4)` `K_(2)HgI_(4)+KOH` `K_(2)HgI_(2)+KOH` `K_(2)HgI_(4)+Hg` Solution :`2KI+HgI_(2) to underset("Nessler's REAGENT")(K_(2)HgI_(4)+KOH)`

Discussion

7.	Nervousness anaemia is caused by the deficiency of vitamin
Answer» `B_1` `B_2` `B_6` `B_(12)` ANSWER :D

Discussion

8.	Nernst equation is given by
Answer» `E_("OX")=E_("ox")^(0)-(0.059)/(N)log_(10)""(["oxidised state"])/(["Reduced state"])` `E_("ox")=E_("ox")^(0)+(0.059)/(n)log_(10)""(["oxidised state"])/(["Reduced state"])` `E_("ox")=E_("ox")^(0)-(0.059)/(n)log_(e)""(["oxidised state"])/(["Reduced state"])` `E_("ox")=E_("ox")^(0)+(0.059)/(n)log_(e)""(["oxidised state"])/(["Reduced state"])` SOLUTION :Formula of NERNST EQUATION.

Discussion

9.	Nernst equation gives the variation of potential of an electrode based on activity of ions temperature and pressure. The equation is E=E^(@) -(2.303RT)/(nF) logQ (or)E=E^@ - (0.0591)/(n) log Q E^@= Standard potential and 'Q' is the reaction quotient. Which cell has least potential ?
Answer» `ZN// UNDERSET(1M)(Zn^(+2))// underset(1M)(Cu^(+2))//Cu` `Zn// underset(0.1M)(Zn^(+2))// // underset(0.1M)(Cu^(+2))// Cu` `Zn // underset(0.1M)(Zn^(+2))// underset(1M)(Cu^(+2))// Cu` `Zn// underset(1M)(Zn^(+2))// underset(0.1M)(Cu^(+2))// Cu` Solution :`E_("cell") = E_("cell")^(0) + (0.0591)/(n) LOG "([Cu^(+2)])/([Zn^(+2)])` ` [Cu^(+2)] uarrE_("cell") uarr ` ` [Cu^(+2)] darr E_("cell")darr` Metallurgy , Refer Ellingham Diagram According to this graph lower line metal reduce upper line metal

Discussion

10.	Nernst equation gives the variation of potential of an electrode based on activity of ions temperature and pressure. The equation is E=E^(@) -(2.303RT)/(nF) logQ (or)E=E^@ - (0.0591)/(n) log Q E^@= Standard potential and 'Q' is the reaction quotient. What is the reduction potential of a hydrogen electrode in an aqueous solution containing 0.1 M NH_4OH,(Kb=10^(-5)), ?
Answer» 0.02 V 0.03 V 0.06 V 0.01 V Solution :`E_1 = E^(0) + (0.06)/(3) LOGC , E_2 = E^(0) +(0.06)/(3) LOG ((C)/(10))` ` (E_2 -E_1) = (0.06)/(3) [log""((C)/(60))-logC] = 0.02 log((C)/(10) xx (1)/(C)) = 0.02 xx log 10^(-1) = -0.02V`

Discussion

11.	nernst equation gives the effect of _____and____on the EMF of a cell.
Answer» CONCENTRATION of ELECTROLYTIC SOLUTIONS TEMPERATURE Both a& b None Solution :Concentration of electrolytic solutions, temperature

Discussion

12.	Nernst equation for cell potential in case of Zn-Cu cell is given by
Answer» `E_("CELL") =E_("cell")^(@) +(RT)/(2F) ln ([Zn^(2+)])/([Cu^(2+)])` `E_("cell") =E_("cell")^(@) -(RT)/(2F) ln ([Zn^(2+)])/([Cu^(2+)])` `E_("cell") = E_("cell")^(@) -(RT)/(2F) ln ([Cu^(2+)])/([Zn^(2+)])` `E_("cell") =E_("cell")^(@) -(RT)/(2T) log ([Zn^(2+)])/([Cu^(2+)])` ANSWER :B

Discussion

13.	Neoprene (synthetic rubber) is a polymer of
Answer» Propene VINYL chloride Chloroprene Butadiene Solution :`UNDERSET("Chlorprene")(n(CH_(2)=underset(Cl)underset(\|)(C)-CH=CH_(2))) to underset("NEOPRENE")((-CH_(2)-underset(Cl)underset(\|)(C)=CH-CH_(2)-)_(n))`

Discussion

14.	Neoprene is prepared from
Answer» ISOPRENE VINYL CYANIDE CHLOROPRENE isobutylene Answer :C

Discussion

15.	Neoprene is the polymer of :
Answer» cis-isoprene BUTADIENE CHLOROPRENE trans-isoprene . ANSWER :C

Discussion

16.	Neoprene is polymer of ........................
Answer» ANSWER :CHLOROPRENE , (2-chloro-1,3-butadiene)

Discussion

17.	Neoprene is formed by
Answer» FREE RADICAL polymerization Cationic polymerisaiton Anionic polymerization CONDENSATION polymerization Answer :A

Discussion

18.	Neoprene is condensation polymer. Is it true or false?
Answer» SOLUTION :BAKELITE is a CONDENSATION POLYMER.

Discussion

19.	Neoprene is condensation polymer.
Answer» SOLUTION :BAKELITE is a CONDENSATION POLYMER.

Discussion

20.	Neoprene, bakelite, Buna-S, Buna-N.
Answer» SOLUTION :Bakelite. It is a thermosetting plastic whereas others are SYNTHETIC RUBBER.

Discussion

21.	Neoprene is a polymer of
Answer» CHLOROPRENE Isoprene Styrene Ethene Answer :A

Discussion

22.	Neopentyl alcoholoverset( +HCl //"anhydrous" ZnCl_2) to A , " Here"'A'is
Answer» NEOPENTYL CHLORIDE n-pentyl chloride 2- Chloropentane ter-pentyl chloride ANSWER :D

Discussion

23.	Neopentane on photochemical chlorination gives three isomeric monochlorides.
Answer»

Discussion

24.	Neon is mainly used in discharge tubes at a pressure of __________ mm
Answer» SOLUTION :5MM

Discussion

25.	Neon is generally used for warning signals. Why?
Answer» Solution :NEON lights are VISIBLE from long distances even in fog and mist and hence neon is GENERALLY USED for warning signals.

Discussion

26.	Neon is generally used for warning signals. Why ?
Answer» Solution :NEON lights are visible from long distances even in fog and mist and HENCE neon is GENERALLY USED for warning SIGNALS.

Discussion

27.	Neon in extensively used in
Answer» COLD STRONGE unit organic compounds medicines coloured ELECTRIC DISCHARGE lamps Solution :N//A

Discussion

28.	Neon is extensively used in:
Answer» COLD STORAGE units Organic compounds Medicines Coloured ELECTRIC DISCHARGE lamps Answer :D

Discussion

29.	Neodymium show +2, +3, and +4 oxidation state of +4 oxidation state. The most oxidising state known is aqueous solution is
Answer» `+2` `+3` `+4` none of these SOLUTION :We know that, +3 oxidation is common in all series. Stable of +3 O.S. depends upon high HYDRATION energy, high lactic energy and high I.P. `Nd^(2+)` - has configuration `4f^(4)` `Nd^(4+)-` has configuration `4f^(2)` HENCE `+2,+4` oxidation states are unstable in Nd in AQUEOUS solution.

Discussion

30.	neo Pentyl chloride on dyhydrohalogenation (using low conc. Of base) yields mainly
Answer» 2- METHYL but 2-ENE 2- Methyl but -1- ene 3- Methyl but -1-ene 2- PENTENE Answer :A

Discussion

31.	Neo - heptyl alcohol has the formula :
Answer» `CH_(3)-underset(CH_(3))underset(\|)OVERSET(CH_(3))overset(\|)(C)-underset(OH)underset(\|)(CH)-CH_(2)CH_(3)` `CH_(3)-underset(OH)underset(\|)overset(CH_(3))overset(\|)(C)-CH_(2)CH_(2)CH_(2)-CH_(3)` `C_(2)H_(5)-underset(C_(2)H_(5))underset(\|)overset(C_(2)H_(5))overset(\|)(C)-OH` `CH_(3)-underset(CH_(3))underset(\|)overset(CH_(3))overset(\|)(C)-CH_(2)CH_(2)CH_(2)OH` Answer :D

Discussion

32.	Nelson cell is used for the preparation of
Answer» SLAKED LIME Baryta Sodium CAUSTIC soda Answer :D

Discussion

33.	Neglecting the liquid junction potential, calculate the emf of the following cell at 25^@C H_2 (1atm) \|0.5 M HCOOH\|\|1M CH_3 COOH\|H_2(1atm) The dissociation constants of HCOOH and CH_3COOH are 1.77 times 10^-4 and 1.8 times 10^-8 respectively.
Answer» SOLUTION :`-0.0246` VOLT

Discussion

34.	Negative deviation from Raoult's Law is observed in whichof the following binary liquid mixtures :
Answer» ETHANOL and acetone benzene and toluene acetone and chloroform acetone and carbnon lisulphide Solution :is the CORRECT ANSWER.

Discussion

35.	Negative catalyst is one :
Answer» Which RETARD the RATE of REACTION Takes the reaction in FORWARD direction Promotes the side reaction None Answer :A

Discussion

36.	Neelam is a class XII student. Her mother fell down and bruised her leg which gave her lot of pain. Neelam gave her mother a non-narcotic analgesic which was safe to use. Her mother questioned if there was some other type of analgesics as well. Neelam replied in the affirmative and told her mother that narcotic analgesics should be taken only when one is in acute pain. After reading the above passage, answer the following questions : (i)What values are expressed by Neelam about narcotic and a non-narcotic analgesics? (ii) Give some examples of narcotic and non-narcotic analgesics. (iii) Give one example of an antipyretic which also acts as an analgesic. How does it work as an analgesic?
Answer» Solution :(i)Neelam expressed values about the safety in CHOOSING analgesics. Whereas non-narcotic analgesics are non-addictive and hence are safe to use, narcotic analgesics are addictive, i.e., habit forming and hence not safe to use. Therefore, narcotic analgesics should be used only in severe pain such as post-operative pain, cardiac pain, pains of TERMINAL cancer and in child birth. (ii) Examples of non-narcotic analgesics are : aspirin, paracetamol, naproxen, ibuprofen and diclofenac sodium, and examples of narcotic analgesics are morphine, codeine and heroin (iii) Aspirin ACTS both as an antipyretic as WELL as analgesic. Its analgesic action is due to the reason that it INHIBITS the synthesis of prostaglandins which stimulate inflammation in the tissues and cause pain.

Discussion

37.	Neeral went to the departmental store to purchase store to purchase groceeries. On one of the shelves he noticwed sugar-free tables. He decided to buy them for his grandfather who was a diabatic. There were three types of sugar-free tablets. He decided to buy sucrolose which was good for his grandfather's health. (i) Name another sugar-free tablet which neeraj did not purchase. ltBrgt (ii) Was it right to purchase such medicines without doctor's prescription? (iii) What qualit of Neeraj is reflected above?
Answer»

Discussion

38.	Nef - carbonyl synthesisis usedto produce
Answer» CARBOXYLICACIDS or esters aldehydesor ketones ALCOHOLS or ethers oxime or amide ANSWER :B

Discussion

39.	Necessary conditions for halogenation are
Answer» Cold and dark presence of HALOGEN CARRIER Both (a) and (b) NONE Answer :C

Discussion

40.	Necessary condition for HVZ reaction (halogenation of fatty acids ) is :
Answer» PRESENCE of catalyst Sunlight BOTH (A) AND (B) None Answer :C

Discussion

41.	Near the top of the blast furnace, iron oxides are reduced to spongy iron by
Answer» C CO `CO_(2)` `CaCO_(3)` ANSWER :2

Discussion

42.	Ne gets more easily adsorbed over charcoal the He. Explain.
Answer»

Discussion

43.	Near the top of a blast furnace employed for the extrction of iron the metal oxides are reduced to spongy iron by :
Answer» CARBON `CO` `CO_2` LIMESTONE ANSWER :B

Discussion

44.	Nd (Z = 60) is a member of group 3 in periodic table. An isotope of it is beta-active. The daughter nuclei will be a member of
Answer» Group -3 Group -4 Group -1 Group -2 Solution :ELEMENT 57 to 71 are placed in III group

Discussion

45.	NCl_3 on hydrolysis yields:
Answer» `N_2 and NOCL` `NO and HCL` `NH_3and HOCL` `N_2O and NH_3` ANSWER :C

Discussion

46.	NCl_3 is possible for nitrogen while NCl_5 is not possible. For phosphorus atom PCl_3 and PCl_5 both are possible. The reason for this is.....
Answer» P-atom POSSESSES VACANT d-orbitals, while N-atom does not POSSESS. The elctronegativity of P is less than that of N. The tendency to form hydrogen BOND for phosphorus is less than that of nitrogen At normal temperature phosphorus is solid, while nitrogen possesses gaseous state. Solution :P-atom possesses vacant d-orbitals, while N-atom does not possess.

Discussion

47.	NCl_(3) gets readily hydrolysed while NF_(3) does not. Why?
Answer» SOLUTION :In `NCl_(3), CL` has vacant d - orbitals to accpet the lone pair of electrons DONATED by O - atom of `H_(2)O` MOLECULES but in `NF_(3)F` does not have d - orbitals. `NCl_(3)+3H_(2)Orarr NH_(3)+3HOCl`, `NF_(3)+H_(2)Orarr"No reaction."`

Discussion

48.	NCI_(5) is not formed because
Answer» it is UNSTABLE nitrogen is inert nitrogen does have d-orbitals nitrogen has small ATOMIC radius. Solution :`NCI_(5)` is not FORMED because N does not have d-orbitals and cannot EXPAND its octet BEYOND cight.

Discussion

49.	NCI_(3) is an endothermic compound while NF_(3) is an exothermic compound.
Answer» Solution :DUE to smaller size of F as compared to CI, the N-F bond is much stronger (272 kJ `mol^(-1)`) than N-CI bond (201 kJ `mol^(-1)`) while bond dissociation energy of `F_(2)` (158.8 kJ `mol^(-1)`) is much lower than that of `CI_(2)` (242.6 kJ `mol^(-1)`). Therefore, ernergy released during the fomation of `NF_(3)` molecule is more than the energy needed to break `N_(2)` (941.4 kJ `mol^(-1)`) and `F_(2)` molecules into individual atoms. In other words, formation of `NF_(3)` is an exothermic REACTION or `NF_(3)` is an exothermic compound. `{:(N_(2)(g)+3F_(2)(g) rarr 2 NF_(3)(g),,""Delta = -214.2 kJ mol^(-1)),(N_(2)(g)+3CI_(2)(g) rarr 2 NCI_(3)(g),,""Delta H = +463.2 kJ mol^(-1)):}` In CONTRAST, energy released during the formation of `NCI_(3)` molecule is less than the energy needed to break `N_(2) and CI_(2)` molecules into individual atoms. In other words, formation of `NCI_(3)` is an endothermic reaction or `NCI_(3)` is an endothermic compound.

Discussion

50.	N(CH_3)_3 is pyramidal but N (SiH_3)_3 is planar-explain.
Answer» Solution :Because of d -orbital RESONANCE, the N-atom in `N(SiH_3)_3` MOLECULE is `sp^2` - hybridised and therefore, the molecule is planar. No such d -orbital resonance OCCURS in `N(CH_3)_3` and the central N-atom is `sp^3` -hybridised. For this reason, this molecule is pyramidal.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Net work done by a system is given by:

Nessler's reagent is used to detect the presence of:

Nessler's reagent is

Nessler's reagent used to test the presence of ammonia or NH_(4)^(+) is

Nessler's reagent is used to detect

Nesseler's reagent is:-

Nervousness anaemia is caused by the deficiency of vitamin

Nernst equation is given by

Nernst equation gives the variation of potential of an electrode based on activity of ions temperature and pressure. The equation is E=E^(@) -(2.303RT)/(nF) logQ (or)E=E^@ - (0.0591)/(n) log Q E^@= Standard potential and 'Q' is the reaction quotient. Which cell has least potential ?

nernst equation gives the effect of _____and____on the EMF of a cell.

Nernst equation for cell potential in case of Zn-Cu cell is given by

Neoprene (synthetic rubber) is a polymer of

Neoprene is prepared from

Neoprene is the polymer of :

Neoprene is polymer of ........................

Neoprene is formed by

Neoprene is condensation polymer. Is it true or false?

Neoprene is condensation polymer.

Neoprene, bakelite, Buna-S, Buna-N.

Neoprene is a polymer of

Neopentyl alcoholoverset( +HCl //"anhydrous" ZnCl_2) to A , " Here"'A'is

Neopentane on photochemical chlorination gives three isomeric monochlorides.

Neon is mainly used in discharge tubes at a pressure of __________ mm

Neon is generally used for warning signals. Why?

Neon is generally used for warning signals. Why ?

Neon in extensively used in

Neon is extensively used in:

Neodymium show +2, +3, and +4 oxidation state of +4 oxidation state. The most oxidising state known is aqueous solution is

neo Pentyl chloride on dyhydrohalogenation (using low conc. Of base) yields mainly

Neo - heptyl alcohol has the formula :

Nelson cell is used for the preparation of

Neglecting the liquid junction potential, calculate the emf of the following cell at 25^@C H_2 (1atm) |0.5 M HCOOH||1M CH_3 COOH|H_2(1atm) The dissociation constants of HCOOH and CH_3COOH are 1.77 times 10^-4 and 1.8 times 10^-8 respectively.

Negative deviation from Raoult's Law is observed in whichof the following binary liquid mixtures :

Negative catalyst is one :

Nef - carbonyl synthesisis usedto produce

Necessary conditions for halogenation are

Necessary condition for HVZ reaction (halogenation of fatty acids ) is :

Near the top of the blast furnace, iron oxides are reduced to spongy iron by

Ne gets more easily adsorbed over charcoal the He. Explain.

Near the top of a blast furnace employed for the extrction of iron the metal oxides are reduced to spongy iron by :

Nd (Z = 60) is a member of group 3 in periodic table. An isotope of it is beta-active. The daughter nuclei will be a member of

NCl_3 on hydrolysis yields:

NCl_3 is possible for nitrogen while NCl_5 is not possible. For phosphorus atom PCl_3 and PCl_5 both are possible. The reason for this is.....

NCl_(3) gets readily hydrolysed while NF_(3) does not. Why?

NCI_(5) is not formed because

NCI_(3) is an endothermic compound while NF_(3) is an exothermic compound.

N(CH_3)_3 is pyramidal but N (SiH_3)_3 is planar-explain.

nernst equation gives the effect of _andon the EMF of a cell.