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.
| 91151. |
(A) C_(7)H_(14) an organic compound decolourises Br_(2) solution to produce (B) which combines with strong base NaNH_(2) to produce (C) which does not give white ppt. with AgNO_(3)//NH_(4)OH. (A) again when treated with Hg(OA c)_(2)//H_(2)O+NaBH_(4) toproduce (D) and when treated with HBr/ROOR then OH^(-) to produce (E). Here (D) and (E) are isomeric alcohol, one is optically acetic and other is optically inactive. Q. What is (A) |
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Answer» `C-C-C-UNDERSET(C)underset(|)(C)=C-C` |
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| 91152. |
A C_(7)H_(12)O_(2) optically active alcohol is oxidised by jones reagent to an optically inactive ketone. The molecule is. |
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Answer»
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| 91153. |
A C_(7)H_(12)O_(2) compound gives a positive Tollen's silver mirror test as well as positive iodoform test.Which of the following would not satisfy these facts? |
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Answer» 2-hydroxy-3,3-dimethylcyclopentanone |
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| 91154. |
A C_(6)H_(12)O compound does not react with Br_(2) in C Cl_(4), produces a flammable gas on treatment with LiAlH_(4), and reacts with H_(2)CrO_(4) changing the color from orange to green. Which of the following compounds best agrees with these facts? |
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Answer» 1-methylcyclopentanol |
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| 91155. |
A C_(5)H_(13)N compound gives a base soluble derivative on reaction with Hinsberg test. Which of the following fits these facts best? |
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Answer» 1,1-Dimethylpropylamine |
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| 91156. |
A (C_(5)H_(12)O) produces, on reaction PCl_(5) from alkyl chloride B and C. B and C both on reaction with aqueous KOH form alcohol D and E . Both D and E give iodoform test. Identify the correct answers. |
| Answer» ANSWER :A::B::D | |
| 91157. |
(A) C_(2)H_(5)OH (B) CH_(3)CHO (C) CH_(3)COCH_(3) (D) C_(6)HCHO (E) C_(6)H_(5)CH_(2)CHO. Number of compounds which not only give yellow ppt with NaOH+I_(2) but also give red ppt with Fehling's reagent are _________ |
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Answer» 4 |
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| 91158. |
(A): C CI_4 can be used as a fire extinguisher. (R): C CI_4 is insoluble in water. |
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Answer» Both A & R are true, R is the correct EXPLANATION of A |
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| 91159. |
(A) C Cl_(3)-CHO on treatment with an alkali to form chloroform and formate ion but not undergo Cannizzaro's reaction even through no alpha-hydrogen. (R) H^(-) is not transfer does not take place because C Cl_(3), is good leaving group. |
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Answer» Both (A) and (R) are TRUE and (R) is the correct explanation of (A) |
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| 91160. |
(a). C-C-overset(O)overset(||)(C)-Cunderset(Delta)overset([O])to ltb rgt (b). Me_(2)CH-overset(O)overset(||)(C)-Meunderset(Delta)overset([O])to (c). Me_(3)C-overset(O)overset(||)(C)-Meunderset(Delta)overset([O])to (d). . |
Answer» SOLUTION :
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| 91161. |
A bydrogenation reaction is carried out at 500 K. If the same reaction is carried out in the presence of a catalyst at the same rate, the temperature required is 400 K. Calculate the activation energy of the reaction if the catalyst lowers the activation energy by 20 kJ mol^(-1). |
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Answer» Solution :Suppose activation energy in the absence of catalyst is `E_(a)` and that in the presence of catalyst, it is `E_(C)`. Then`K=Ae^(-E_(a)//400"R")("as k is same in both the cases").` Hence, `(E_(a))/(500" R")=(E_(c))/(400" R")" or "E_(c)=(4)/(5)E_(a)` But `E_(a)-E_(c)=20" kJ"" or "E_(a)-(4)/(5)E_(a)=20" or "(1)/(5)E_(a)=20" or "E_(a)=100" kJ MOL"^(-1).` |
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| 91162. |
A buttonn cell used in watchesfunction as followingZn(s) +Ag_(2)O(s) +H_(2)O(l) rarr 2Ag(s)+Zn^(2+)(aq)+2OG^(-)(aq), E^(@)=0.34 V the cellpotential will be |
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Answer» 1.10 V `Zn^(2+) (aq)+2e^(-) RARR Zn(s) , E^(@)= -0.76 V` cathodehalfcell is `Ag_(2) O(s)+H_(2)O(I)+2e^(-) rarr 2Ag(s)+2OH^(-) (aq)` `E^(@)=0.34 V` `E_(cell)^(@)=E_(CATHODE)^(@) - E_(anode)^(@) =0.34 -(-0.76) =+1.10 V` |
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| 91163. |
A button cell used in watches functions as follows: Zn(s)+Ag_(2)O(s)+H_(2)O(l)hArr2Ag(s)+Zn^(2+)(aq)+2OH^(-)(aq) The half-cell potential are Zn^(2+)(aq)+2e^(-)toZn(s),E^(@)=-0.76V Ag_(2)O(s)+H_(2)O(l)+2e^(-)to2Ag(s)+2OH^(-)(aq),E^(@)=0.34V The cell potential will be |
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Answer» 1.10 V |
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| 91164. |
A button cell used in watches function as following Zn(s)+Ag_(2)O(s)+H_(2)O(l)hArr2Ag(s)+Zn^(2+)(aq)+2OH^(-)(aq) if half cell potential are Zn^(2+)(aq)+2e^(-)toZn(s), Ag_(2)O(s)+H_(2)O(l)+2e^(-)to2Ag(s)+2OH^(-)(aq),E^(@)=0.34V The cell potential will be |
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Answer» 1.34V `Ag_(2)O(s)+H_(2)O(l)+2e^(-)to2Ag(s)+2OH^(-)(aq),E^(o)=0.34V` `Zn(s)+Ag_(2)O(s)+H_(2)O(l)+2e^(-)to2Ag(s)+2OH^(-)(aq)` `+2OH^(-)(aq),E_(CELL)=?` `E_(cell)^(o)=(E_(R.P.)^(o))_("cathode")-(E_(R.P.)^(o))_("anode")` `E_(cell)^(o)=0.34(-0.76)=1.10V` `E_(cell)=E_(cell)^(o)=1.10V` |
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| 91165. |
A button cell used in watches functions as following : Zn_((s)) + Ag_(2)O_((s)) + H_2O_((l)) |
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Answer» 1.10 V |
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| 91166. |
A : But-2-ene is more stable than propene. R : Heat of hydrogenation of but-2-ene is lesser than that of propene. |
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Answer» If both Assertion & Reason are TRUE and the reason is the correct explanation of the assertion, then MARK (1). |
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| 91167. |
A bulb of unknown volume contained an ideal gas at 650 mm pressure. A certain amount of gas was withdraw and found to occupy 1.52 cc at 1 atm pressure. The pressure of the gas remaining in the bulb was 600 mm. If all measurements were made at a constant temperature, find the volume of the bulb. |
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Answer» SOLUTION :When a certain amount of the gas is WITHDRAWN, the pressure dropped from 650 mm to 600 mm. So the pressure difference (650 - 600) ot 50 mm will be the pressure of the gas withdrawn which occupied the bub of volume `V_(1)` cc (suppose). SINCE the same amount of withdrawn gas occupied 1.52 cc at 1 atm (760 mm) pressure at the same TEMPERATURE, we can apply Boyle.s law : `p_(1)V_(1) = p_(2)V_(2)` `50 xx V_(1) = 760 xx 1.52` `V_(1) = 23.1` cc. |
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| 91168. |
A bulb of unknown volume V contains an ideal gas at 1 atm pressure. This bulb was connected to another evacuated bulb of volume 0.5 litre through a stopcock. When the stopcock was opened the pressure at each became 530 mm while the temperature remained constant. Find V in litres. |
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Answer» Solution :Since on openingthe stopcock, the same NUMBER of moles of the gas occupy a VOLUME of (V + 0.5) litre at the same temperature, We apply Boyle.s LAW : `p_(1)V_(1) = p_(2)V_(2)` `1 xx V = (530)/(760) xx (V + 0.5) ""(p_(2) = (530)/(760)"atm")` `V = 1.152` litres. |
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| 91169. |
A bulb emits light of wavelength 4500Å. The bulb is rated as 150 watt and 8% ofthe energy is emitted as light. How many photons are emitted per sec? |
| Answer» SOLUTION :`2.72xx10^(19)` | |
| 91170. |
A bulb contains 2 moles of H_2at a pressure of 0.8 atm and temperature T K. 0.6 mole of O_2is added to this bulb and the temperature of the bulb is lowered by 15 K to keep the same pressure. Calculate the volume of the bulb and its temperature T. Also, calculate the partial pressure of each gas. |
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Answer» <P> SOLUTION :`13.34 dm^3, 65 K, p_(H_2) = 0.615 ATM, p_(O_2) = 0.185 atm` |
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| 91171. |
A buffer solution with pH 9 is to be prepared by mixing NH_(4)Cl and NH_(4)OH. Calculate the number of moles of NH_(4)Cl that should be added to one litre of 1.0 M NH_(4)OH. [ K_(b) = 1.8 xx 10^(-5)] |
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Answer» 3.4 `pH = -log[1.8 xx 10^(-5)] + log.(["Salt"])/(1.0)` `9 = 4.7 + log.(["Salt"])/(1.0)` `log.(["Salt"])/(1.0) = 9 - 4.7 = 4.3` `(["Salt"])/(1.0)= "Antilog" (1)/(4.3), ["Salt"] = 1.8`. |
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| 91172. |
A buffer solution is prepared in which the concentration of NH_(3) is 0.30 M and the concentration of NH_(4)^(+) is 0.20 M. If the equilibrium constant, K_(b) for NH_(3) equals 1.8 xx 10^(-5), what is the pH of this solution (log 2.7 = 043) |
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Answer» 8.73 `= 4.74 + log.(0.20)/(0.30) = 4.74 + (0.301 - 0.477)` `= 4.74 - 0.176 = 4.56:. PH = 14- 4.56 = 9.44`. |
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| 91173. |
A buffer solution is prepared in which the concentration of NH_(3) is 0.30 M and concentration of NH_(4)^(+) is 0.20 M. If equilibrium constant K_(b) for NH_(3) equals 1.8xx10^(-5), what is the pH of the solution ? |
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Answer» `9.08` `pK_(b)=-LOG K_(b)=-log(1.8xx10^(-5))=4.74` `pOH=4.74+log((0.20)/(0.30))=4.56` `pH=14-4.56=9.44` |
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| 91174. |
A buffer solution is prepared by mixing equal concentration of acid (ionisation constant K_(a)) and a salt. The pH of buffer is |
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Answer» `pK_(a) + 7` `pH = pK_(a) + LOG.(["SALT"])/(["acid"])` Since, [salt] = [acid], `pH = pK_(a)`. |
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| 91175. |
A buffer solution is prepared by mixing 'a' moles of CH_(3)COONa and 'b' moles of CH_(3)COOH such that (a+b) = 1, into water to male 1L buffer solution. If the buffer capacity of this buffer solution is plotted against moles of salt CH_(3)COONa 'a' then the plot obtained will be (to the scale) approximately. (As shown in fig. in options) |
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Answer»
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| 91176. |
A buffer solution helps in maintaining the : |
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Answer» ALKANITY of solution |
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| 91177. |
A buffer solution has equal volumes of 0.2 M NH_(4)OH and 0.02 M NH_(4)Cl. The pK_(b) of the base is 5. The pH is |
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Answer» 10 `= 5 + log.(0.02)/(0.2) = 5 + log.(1)/(10) = 5 + (-1) = 4` `pH = 14 - pOH = 14 - 4 = 10`. |
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| 91178. |
A buffer solution has equal volumes of 0.2 M NH_(4)OH and 0.02 M NH_(4) CI The pk_(b) of the base is 5. The pH is |
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Answer» A) 10 `=5+log(0.02)/(0.2)=5+log(1)/(10)=5+(-1)=4` `pH=14-pOH=14-4=10` |
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| 91179. |
A buffer solution contains 0.1 mole of sodium acetate in 1000 cm^(3) of 0.1 M acetic acid. To the above buffer solutions, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is equal to............ |
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Answer» `pK_(a) - log_(2)` `["Salt"] = (0.1 + 0.1)/(1000 ml) = (0.2)/(1) = 0.2` `["Acid"] = (0.1)/(1000 ml) = (0.1)/(1) = 0.1` `pH = pK_(a) + log 2` `:. pH = 14 - 2 RARR pH = 12`. |
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| 91180. |
A buffer solution contains 0.1 mole of sodium acetate in1000 cm^(3) of 0.1 M acetic acid. To the above buffer solution, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is equal to |
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Answer» `pK_(a) + LOG 2` |
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| 91181. |
A buffer solution contains 0.1 mole of sodium acetate dissolved in 1000 cm^(3) of 0.1 M acetic acid. To the above buffer solution, 0.1 mole of sodium acetate is further added and dissolved.The pH of the resulting buffer is |
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Answer» `pK_(a)` `0.1+0.1=0.2` `pH=pK_(a)+"log"([CH_(3)COONa])/([CH_(3)COOH])` `pH=pK_(a)+"log"(0.2)/(0.1)=pK_(a)+log2`. |
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| 91182. |
A buffer solutioncontains 0.1 M of acetic acid and 0.1 M of sodium acetate. What will be its pH, it pK_(a) of acetic acid is 4.75 |
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Answer» `4.00` `pH = 4.75 + log 1, pH = 4.75`. |
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| 91183. |
A buffer solution contains 0.1 M each of acetic acid and sodium acetate. The pH of the buffer solution is (pK_(a)(CH_(3)COOH)=4.75) : |
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Answer» `4.75` `=4.75+log 1=4.75` |
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| 91184. |
A buffer solution containing 0.1 mole of ammonium hydroxide and 0.15 mole of ammonium chloride per litre of the solution. Calculate the pH of the buffer solution. K_b for ammonium hydroxide is 1.8 xx10^(-5). |
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Answer» SOLUTION :This is a buffer mixture containing a weak base and its salt. Hence the equation to be USED is `pOH=pK_b+log.(["salt"])/(["base"])` `pK_b=log K_b` `=-log 1.8-log 10^(-5)=4.7447` `therefore pOH=4.7447+log.(0.15)/(0.10)` `pOH=4.7447+log 1.5` `=4.7447+0.1761=4.9208` `pH+POH=14` `pH=14-4.9208=9.0792` `PH=9.08` |
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| 91185. |
A buffer mixture of acetic acid and potassium acetate has pH= 5.24. The ratio of [CH_3COO^-]/[CH_3COOH] in this buffer is, (pK_a = 4.740): |
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Answer» 3:1 |
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| 91186. |
A bufer solution was prepared by dissolving 0.05 mol formic acid & 0.06 mol sodium formate in enough water to make 1.0 L of solution. Ka for formic acid is 1.80 xx 10^(-4) If the solution in (b) were diluted to 10 times its volume, what would be the pH ? |
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Answer» |
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| 91187. |
A bubble of air is underwater at temperature 15^(@)C and the pressure 1.5 bar. If the bubble rises to the surface where the temperature is 25^(@)C and the pressure is1.0 bar, what will happen to the volume of the bubble? |
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Answer» Volume will become GREATER by a factor of 1.6 `Vprop T/P` Given `T_(1)=15+273=287, P_(1)=1.5` BAR `T_(2)=25+273=298, P_(2)=1` bar `V_(1)prop 288/1.5` i.e. `V_(1)prop 192` `V_(2)prop 298/1implies(V_(2))/(V_(1))=298/192=1.55~~1.6` |
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| 91188. |
A bubble of 8 moles of helium is submerged at certain depth n water. The temperature of water increases by 30^(@)C. How much heat is added approximately to helium (in kJ) during expansion? |
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Answer» |
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| 91189. |
A+Bto products, the kinetic data of the reaction is {:(A("m. lit"^(-1)),B("m. lit"^(-1)),"Rate"("m. lit"^(-1)"Sec"^(-1))),((1)0.5,0.5,2.xx10^(-4)),((2)0.5,1.0,1.99xx10^(-4)),((3)1.0,0.5,2.01xx10^(-4)):} The order of the reaction is |
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Answer» ONE |
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| 91190. |
A+Bto products is an elementary reaction. When excess of A is taken in this reaction, then the molecularity and other are respectively |
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Answer» 2 & 2 |
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| 91191. |
A brown ring is formed in the ring test for NOg ion. It is due to the formation of |
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Answer» `[Fe(H_(2)O)_(5) (NO)]^(2+)` |
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| 91192. |
A brown ring is formed in the ring test for NO_3^(-) ion. It is due to the formation of |
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Answer» `[FE(H_2O)_5(NO)]^(2+)` |
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| 91193. |
A brown coloured mixture of two gases is obtained by the reduction of 6N nitric acid with metallic copper. The mixture on cooling condenses to a blue liquid which on freezing (-30^@ C) gives a blue solid.The correct choice for blue liquid or solid is : |
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Answer» It is REFERRED to as the ANHYDRIDE of nitrous acid `NO+NO_2 OVERSET(-20^@C)HARR N_2O_3 ("blue"), (A) 2HNO_2 to N_2O_3 +H_2O` (B)`N_2O_2+2KOH to 2KNO_2+ H_2O` (C )`2NHO_3 + As_2O_3 + 2H_2O to` All options are correct. |
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| 91194. |
A brown ring appears in the test for |
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Answer» Nitrate |
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| 91195. |
A brown coloured mixture of two gases is obtained by the reduction of 6N nitric acid with metallic copper. Condeness to a blue liquid which on freezing at -30^(@)C gives a blue solid. The correct choice for blue liquid or solid is . |
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Answer» It is referred to as the anhydride of nitrous acid |
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| 91196. |
(A): Bromine does not displace chlorine from its salt solution (R): Chlorine is displaced from its oxysalt by bromine |
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Answer» Both (A) and (R ) are true and (R ) is the CORRECT EXPLANATION of (A) |
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| 91197. |
A brown colloidal solution of platinum was prepared by ........... in 1898. |
| Answer» SOLUTION :GEORGE BREDIG | |
| 91198. |
A broad spectrum antibiotic is |
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Answer» PARACETAMOL |
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| 91199. |
What are broad spectrum antibiotics. |
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Answer» Paracetamol |
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| 91200. |
A bright cone of light is called .......... in Tyndall effect. |
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Answer» TYNDALL CONE |
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