InterviewSolution
Saved Bookmarks
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.
| 301. |
Which compound does not give oxygen on heating?A. `HgO`B. `KMnO_(4)`C. `(NH_(4))_(2)Cr_(2)O_(7)`D. `KClO_(3)` |
|
Answer» Correct Answer - C `(NH_(4))_(2)Cr_(2)O_(7)` on heating gives `N_(2)`. `(NH_(4))_(2)Cr_(2)O_(7)overset(Delta)(rarr)N_(2)+Cr_(2)O_(3)+4H_(2)O`. |
|
| 302. |
A green coloured solution of a salt changes its colour to light pink on passing ozone through it. Which of the following species represent pink and green colour respectively.A. `Mn^(2+)` and `MnO_(2)`B. `MnO_(4)^(2-)` and `MnO_(4)^(-)`C. `MnO_(4)^(-)` and `MnO_(4)^(2-)`D. `Cu^(+)`and `Cu^(2+)` |
|
Answer» Correct Answer - C `MnO_(4)^(-)` is pink while `MnO_(4)^(2-)` is green, ozone oxidizes `MnO_(4)^(2-)` to `MnO_(4)^(-)` |
|
| 303. |
A green coloured solution of a salt changes its colour to light pink on passing ozone through it. Which of the following species represent pink and green colour respectively.A. `Mn^(2+)` and `MnO_(2)`B. `MnO_(4)^(2-)` and `MnO_(4)^(-)`C. `MnO_(4)^(-)` and `MnO_(4)^(2-)`D. `Cu^(+)` and `Cu^(2+)` |
|
Answer» Correct Answer - C `MnO_(4)^(-)` is pink while `MnO_(4)^(2-)` is given ,ozone oxidizes `MnO_(4)^(2-)` to `MnO_(4)^(-)`. |
|
| 304. |
When excess of `NaOH` solution is added in potash alum the product is.A. a white precipateB. bluish white precipateC. a clear solutionD. a crystalline mass |
|
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)+6NaOHto2Al(OH)_(3)darr("white")+3Na_(2)SO_(4),),(Al(OH)_(3)+OH^(-)to[Al(OH)_(4)]^(-)("soluble complex")):}` |
|
| 305. |
How many of the following compounds have peroxy linkage? `H_(3)PO_(5),H_(2)SO_(5),H_(2)S_(2)O_(8),HNO_(4),H_(4)P_(2)O_(7),H_(2)S_(2)O_(3),H_(2)S_(2)O_(6).` [If your answer is 2 then write the answer as 0002.] |
|
Answer» Correct Answer - `0005` `H_(3)PO_(5),H_(2)SO_(5),H_(2)S_(2)O_(8),H_(4)P_(2)O_(8),HNO_(4)` |
|
| 306. |
What may be expected to happen when phosphine gas is mixed with chlorine gas?A. The mixure only cools downB. `PCl_(3)` and `HCl` are formed and the mixure warms upC. `PCl_(5)` and `HCl` are formed and the mixure cools downD. `PH_(3).Cl_(2)` is formed with warming up |
|
Answer» Correct Answer - C `PH_(3)+4Cl_(2)rarrPCl_(5)+3HCl` |
|
| 307. |
What may be expected to happen when phosphine gas is mixed with chlorine gas ?A. `PCI_3` and HCI are formed and themixture warms upB. `PCI_5` and HCI are formed and the mixture cools downC. `PH_3 Cl_2` is formed with warming upD. The mixture only cools down |
|
Answer» Correct Answer - B `PH_3 + 4Cl_2 to PCl_5 + 3HCl` |
|
| 308. |
A red solid is insoluble in water. However, it becomes soluble if some KI is added to water. Heating the red solid in a test tube results in liberation of some violet coloured fumes and droplets of a metal appear on the cooler parts of the test tube. The rod solid is:A. `HgI_2`B. HgOC. `Pb_3O_4`D. `(NH_4)_2Cr_2O_7` |
|
Answer» Correct Answer - A `underset"(insoluble)"(HgI_2) + KI to underset"(soluble)"(K_2HgI_4)` |
|
| 309. |
An aqueous solution of a substance gives a white percipitate on treatment with dil `HCl`, which dissole on heating. On passing `H_(2)S` in hot acidic solution a black percipitate is formed. The substance is:A. `Hg_(2)^(2+)`saltB. `CU^(2+)` saltC. `Ag^(+)` saltD. `Pb^(2+)` salt |
|
Answer» Correct Answer - D `PbCl_(2)` is soluble in hot water but insoluble in cold water. `Pb^(2+)+2HCloverset(Delta)tounderset("soluble")(PbCl_(2))overset(H_(2)S)tounderset("black")(PbS)` |
|
| 310. |
Trisilicylamine is a weaker bse than trimethylamine. Explain. |
| Answer» In trisilicylamine `(SiH_(3))_(3)N`, the ione elec tron pair on the nitrogen atom is involved in `p pi-p pi` bondoing with the vacant 3d orbitals on silicon atom. As a result, it is not as easily available to the attacking Lewis acid as in case of trimethylamine `(ch_(3))_(3)N`. whre the electron pair is rather free. | |
| 311. |
Carbon dioxide is a gas but silica is a solid because:A. `CO_(2)` molecules are lighter than `SiO_(2)` moleculesB. carbon dioxide is composed of descreate covalent `CO_(2)` molecules whereas silica has continuous tetrahedral structureC. `CO_(2)` is more acidic than `SiO_(2)`D. melting point of silica is very high |
| Answer» Correct Answer - B | |
| 312. |
Nuclear fusion producesA. ArgonB. DeuteriumC. HeliumD. Krypton |
|
Answer» Correct Answer - C Fusion of H nuclei at very high temperature produces He nucleus. (Thermonuclear reaction) |
|
| 313. |
The inert gases can be isolated and separated byA. electrolysis of their compoundB. fractional distillation of liquid airC. adsorption and desorption on charcoalD. both (b) and (c) |
|
Answer» Correct Answer - D Separation, isolation is done by coconut charcoal by adsorption, desorption process. |
|
| 314. |
Noble gases do not react with other elements becauseA. they are monoatomicB. they are found in abundanceC. the size of their atom is very smallD. they have completely paired up and stable electron shells |
|
Answer» Correct Answer - D Octet configuration -`ns^2 np^6`, all electrons are paired |
|
| 315. |
Elements of group 18 are known as noble gases becauses:A. they were discovered by noble kings of ancient timesB. they were extremely rare in atmosphereC. their valence shell orbitals are completely filled and therefore, react with a few elements only under certain conditionsD. None of the above |
| Answer» Correct Answer - C | |
| 316. |
Noble gases do not react with other elements becauseA. they are monoatomicB. they are found in abundanceC. the size of their atoms is very smallD. they are completely paired up and have stable electron shells |
|
Answer» Correct Answer - D In general , noble gases are not very reactive, Their chemical inertness is due to the fact that they have completely filled `ns^(2)np^(6)` electronic configuration of their valence shells. The other reasons are very high ionisation enthalpy and almost zero electron affinity. |
|
| 317. |
`Br_(2)+underset(HOT)OH^(o+)rarr(A)+(B)` `(A)+(B)+H^(o+)rarr Br_(2)` (A) gives yellow precipitate with `AgNO_(3)`. (A) and (B) are |
|
Answer» `Br_2+OH^(-)("hot") to Br^(-)+BrO_3^-` `Br^(-)+BrO_(3)^(-) overset ("distillation")to Br_2` |
|
| 318. |
`A+Br_(2)+N_(2)+(B) overset(NaOH)rarr(A)` if A is a basic gas then identify (A) and (B)A. `NH_(3),NH_(4)Br`B. `NH_(3),N_(2)O`C. `NH_(3),N_(2)O_(5)`D. None of these |
| Answer» Correct Answer - A | |
| 319. |
Elements of group `14`A. exhibit oxidation state of +4 onlyB. exhibit oxidation state of +2 and +4C. form `M^(2-) " and " M^(4+)` ionsD. form `M^(2+)` and `M^(4+)` ions |
| Answer» Correct Answer - D | |
| 320. |
Which nitrogen halide is least stable thermodynamically?A. `NF_(3)`B. `NCl_(3)`C. `NBr_(3)`D. `NI_(3)` |
| Answer» Correct Answer - D | |
| 321. |
Thermodynamically the most stable form of carbon isA. diamondB. graphiteC. fullerencesD. coal |
| Answer» Correct Answer - B | |
| 322. |
Statement -1 : `NO_(2)` and `CIO_(2)` both being odd electron molecules dimerise. Statement -2 : On dimerisation, `NO_(2)` is coverted to stable `N_(2)O_(4)` molecule with even number of electrons.A. Statement -1 and Statement- 2 both are False.B. Statement -1 is true, Statement- 2 is false.C. Statement -1 is true , Statement-2 is true, Statement-2 is a correct explantion for Statement -1.D. Statement -1 is False, Statement- 2 is True. |
|
Answer» Correct Answer - D `CIO_(2)` does not dimerise because odd electron is present in `d` orbital and is declocalised. But in `NO_(2)` it is present in `sp^(2)` hybrid orbital and thus can dimerise to form `N_(2)O_(4)`. |
|
| 323. |
Ammonium nitrate decomposes on heating intoA. Ammonia and nitric acidB. Nitrous oxide and waterC. Nitrogen, hydrogen and ozoneD. Nitric oxide, nitrogen dioxide and hydrogen |
|
Answer» Correct Answer - B `underset((S))NH_(4)NO_(3)overset(Delta)rarr(2H_(2)Ouarr)+underset(("Laughing gas"))underset("Nitroge oxide")((N_(2)O)uarr)` |
|
| 324. |
Among the following nitrates, silver nitrates, lead nitrate, silver nitrate and ammonium nitrate, the one that decomposes without leaving any solid residue isA. Lead nitrateB. Ammonium nitrateC. Silver nitrateD. Sodium nitrate |
|
Answer» Correct Answer - B `NH_(4)underset((s))NO_(3)overset(Delta)(rarr)2H_(2)O-+N_(2)Ouarr` `Naunderset((s))(N)O_(3)overset(Delat)(rarr)Naunderset((s))(N)O_(2)+O_(2)uarr` `underset(Lunar caustic)(2AgNO_(3)(s)rarr2Ag(s)+2NO_(2)(g)+O_(2)(g)` `2Pb(NO_(3))_(2)rarr2underset((s))(Pb)O+4NO_(2)uarr+O_(2)uarr` |
|
| 325. |
A deep brown gas is formed by mixing two colourless gases which areA. `NO_2` and `O_2`B. `NO` and `O_2`C. `N_2O` and NOD. `NH_3` and HCl |
|
Answer» Correct Answer - B `2NO+O_2 to 2NO_2` Brown gas |
|
| 326. |
A gas is obtained on heating ammonium nitrate.The gas:A. causes laughterB. brings tears to the eyesC. is acidic in natureD. is basic in nature |
|
Answer» Correct Answer - A `NH_(4)NO_(3)overset(Delta)to N_(2)O+2H_(2)O` `N_(2)O` is a colorless neutral gas. It process laughter so it is called as laughing gas. Note : Picrin is tear gas. |
|
| 327. |
Which oxide of nitrogen is obtained on heating ammonium nitrate at `250^@C`?A. Nitric oxideB. Nitrous oxideC. Nitrogen dioxideD. Dinitrogen tetraoxide |
|
Answer» Correct Answer - B `NH_4NO_3 oversetDeltatoN_2O + 2H_2O` |
|
| 328. |
`Me_(2)SiCl_(2)` on hydrolysis will produceA. `(Me)_(2)Si=O`B. C. `Me_(2)SiCl(OH)`D. `(Me)_(2)Si(OH)_(2)` |
| Answer» (d) `(Me)_(2)SiCl_(4)` on hydrolysis will yield `(Me)_(2)Si(OH)_(2)` | |
| 329. |
Reaction of diborane with ammonia gives initiallyA. `B_(2)H_(6).NH_(3)`B. BorazoleC. `B_(2)H_(6).3NH_(3)`D. `[BH_(2)(NH_(3))_(2)]^(+)[BH_(4)]^(-)` |
|
Answer» Correct Answer - D `3B_(2)H_(6) +6NH_(3) rarr 3[BH_(2)(NH_(3))_(2)]^(+)[BH_(4)]^(-) rarr underset("Borazine")(2B_(3)H_(3)H_(6) ) + 12 H_(2)` |
|
| 330. |
Out of following forms of sulphur `S_(8),S_(6)` and `S_(2)` which one is paramagnetic in nature and why ? |
| Answer» Correct Answer - A::B::C::D | |
| 331. |
What happens when one mole of per oxodisulphuric acid reacts with one mole of water (partial hydrolysis) and excess of water (complete hydrolysis ) ? |
| Answer» Correct Answer - A::B::C::D | |
| 332. |
Amongest `H_(2)O,H_(2)S,H_(2)Se` and `H_(2)Te` the one with highest boiling point is :A. `H_(2)O` because of hydrogen bondingB. `H_(2)Te` because of higher molecular weightC. `H_(2)S` because of hydrogen bondingD. `H_(2)Se` because of lower molecular weight |
|
Answer» Correct Answer - A |
|
| 333. |
On moving down the group forms `H_(2)O` to `H_(2)`Te acidic strength increases, why ? |
| Answer» Correct Answer - A::B::C::D | |
| 334. |
Which allotropic of carbon is thermodynamically more stable ? |
| Answer» Correct Answer - Graphite | |
| 335. |
Which allotropic form of sulphur is thermodynamically stable at room temperature ? |
| Answer» Correct Answer - B::C | |
| 336. |
Which allotropic of carbon is thermodynamically more stable ?A. WhiteB. RedC. BlackD. Yellow |
| Answer» Correct Answer - C | |
| 337. |
Oxygen molecule exhibitsA. ParamagnestismB. DiamagnetismC. FerromagnetismD. Ferrimagnetism |
|
Answer» Correct Answer - A Oxygen molecule exhibits paramagnetism because of two unpaired electrons in the antibonding molecular orbitals. |
|
| 338. |
Oxygen molecule exhibitsA. ParamagnestismB. DiamagnetismC. FerromagbetismD. Ferrimagnetism |
|
Answer» Correct Answer - A Paramagnetism because of two unpaired electrons in the antibonding molecular orbitals. |
|
| 339. |
`P_(4)+NaOH undeset("warm")` to Products. Explaine the reducing character of one of the products obtained by taking the example of copper sulphate. |
|
Answer» `P_(4) + 3 NaOH + 3 H_(2)O to PH_(3) underset("sodium hypophosphite")(+ 3 NaH_(2)PO_(2))` `4Cu^(2+) + PH_(3) + 4H_(2)O to H_(3)PO_(4) +4Cu darr +8H^(+)` Sodium hypophosphite also acts as a strong reducing agent and reduces copper sulphate to `Cu_(2)H_(2)`. |
|
| 340. |
Write the formulae of the compounds, in which oxygen has positive oxidation states and mention the oxidation states of oxygen in them. |
|
Answer» In `OF_(2)` and `O_(2)F_(2)` oxygen has positive oxidation states. `to` In `OF_(2)`, oxygen oxidation state is + 2. `to` In `O_(2)F_(2)` oxygen oxidation state is + 1. |
|
| 341. |
Give the names and formulae of the compounds in which sulphur exhibits an oxidation state of (A)`-2` , (B)`+4` , ( C)`+6` |
| Answer» (A)`H_(2)S^(2-)` , (B)`S^(4+)O_(2)` , ( C)`S^(+6)O_(3)` | |
| 342. |
Copper molecule exhibitsA. `SO_(2)`B. `SO_(3)`C. `H_(2)S`D. `O_(2)` |
|
Answer» Correct Answer - A `Cu+2H_(2)SO_(4)rarrCuSO_(4)+2H_(2)O+SO_(2)` |
|
| 343. |
`AlCl_(3)` achives stability by forming a dimer. Structure of the dimer isA. B. C. D. None of the above |
| Answer» Correct Answer - (b) | |
| 344. |
Nitrogen can be prepared by:A. decomposition of sodium azideB. decomposition of ammonium dichromateC. decomposition of ammonium nitrateD. all of the above |
| Answer» Correct Answer - D | |
| 345. |
Iron is dropped in dil. `HNO_(3)` , it givesA. ferric nitrateB. ferric nitrate and `NO_(2)`C. ferrous nitrate and ammonium nitrateD. ferrous nitrate and nitric oxide |
|
Answer» Correct Answer - C `4Fe + underset("Dil.")(10HNO_(3)) to underset("Ferrous nitrate ")(4Fe(NO_3)_(2))+underset("Ammonium nitrate ")(NH_(4)NO_(3))+3H_(2)O` |
|
| 346. |
Copper exhibits only +2 oxidation state in its stable compounds. Why?A. copper is transition metal in +2 stateB. `+2` state compounds of copper are formed by exothermic reactionsC. Electron configuration of copper in +2 state is `[Ar]3d^(9)4s^(0)`D. Copper gives coloured compounds in +2 state |
| Answer» Correct Answer - B | |
| 347. |
`AlCl_(3)` forms dimer `Al_(2)Cl_(6)` but dissolves in water forming `[Al(H_(2)O)_(6)]^(3+)` and `Cl^(Ө)` ions. Aqueous solution of `AlCl_(3)` is acidic due to hydrolysis.A. If both assertion and reason are true and the reason is the correct explanation of teh assertion.B. If both assertion and reason are true but reason in not the correct explation of the assertion.C. If assertion is true but reason is false.D. Ifassertion is false but reason is true. |
|
Answer» Correct Answer - B Assertion: In gaseous phase and in non-polar solvent like benzene `AlCl_(3)` exists as dimer, `Al_(2)Cl_(6)`. High enthalpy of hydration in water breaks the covalent dimer forming `[Al(H_(2)O)_(6)]^(3+)` and `3Cl^(-)`. Reason: `AlCl_(3)+3H_(2)OtoAl(OH)_(3)+3HCl` |
|
| 348. |
Complete the following reactions. `("NH"_(4))_(2)+"Cr"_(2)"O"_(7)overset(Delta)to` |
| Answer» `(NH_(4))_(2)+"Cr"_(2)O_(7)overset(Delta)toN_(2)+4" H"_(2)O+"Cr"_(2)O_(3)` | |
| 349. |
Which metal will give nitrous oxide by cold and dil `HNO_(3)`?A. ZnB. CuC. PbD. Ag |
| Answer» Correct Answer - A | |
| 350. |
Complete the following reactions. Decomposition of nitrous acid |
| Answer» `3"HNO"_(2)to"HNO"_(3)+2" NO"+"H"_(2)O` | |