InterviewSolution
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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.
| 4551. |
List four observation that helps us to determine whether a chemical reaction has taken place. |
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Answer» SOLUTION :(i) EVOLUTION of gas (ii) CHANGE in temperature (iii) Change in state (iv) Change in COLOUR. |
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| 4552. |
List any two uses of plaster of Paris. |
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Answer» Solution :(a) PLASTER of Paris is used for making toys and MATERIALS for decoration (b) It is used for making surfaces smooth. (c ) It is ALSO used in medicine to MAKE plaster casts to immobilize broken BONES while they heal. |
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| 4553. |
List any two practices that can be followed to dispose off the waste produced in our homes. |
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Answer» Solution :Partices for waste disposal at homes can be: (i) Kitchen waste can be put in a PIT which will CONVERT to manure over time. (ii) Newspapers, magazines ETC., should be SENT for recycling. (ii) Metal cans and GLASS bottles too should be sent for recycling. |
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| 4554. |
List any two properties of the elements belonging to the first group modern periodic table. |
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Answer» SOLUTION :FIRST GROUP of elements are also called alkali metals: a] These elements exhibits valency b] These are very REACTIVE elements and not FOUND freely in nature. |
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| 4555. |
List any two observations when a highly reactive metal is dropped in water. |
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Answer» Solution :(i) large amount of HEAT is EVOLVED. (II) Metal starts FLOATING. |
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| 4556. |
List any two causes for the failure of sustained availability of ground water |
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Answer» SOLUTION :i) LOSS of vegetation COVER ii) POLLUTION from industrical effluents |
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| 4557. |
List any four differences between soaps and detergents. |
Answer» SOLUTION :DIFFERENCE between SOAPS and DETERGENTS : 
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| 4558. |
Write any four physical properties of metals. |
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Answer» Solution :(i) METALS are usually hard (Exceptions are: sodium and potassium) (II) There are sonorous (III) These are lustrous (iv) Metals exhibit melleability and ductility (iv) They exhibit HIGH tensil strength and have high densities. |
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| 4560. |
Linear overlapping of any two pure atomic p-orbitals lead to ______ bond formation. |
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Answer» |
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| 4561. |
Limestone on heating gives |
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Answer» washing soda |
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| 4562. |
Limestone ,chalk and marble are different physical forms of calcium oxide. |
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Answer» SOLUTION :FALSE Correct statement:LIME stone ,CHALK and marble are DIFFERENT physical forms of calcium carbonate. |
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| 4563. |
Lime is prepared by the thermal decomposition of calcium carbonate. |
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| 4565. |
Lighta Bunsenburnerand adjustthe airholeat thebasetogetdifferenttypesofflames/ presenceofsmoke whendoyouget yellowsootyflame? whendo yougeta blueflame ? |
Answer» SOLUTION :WHENTHE airholeis completelyopentheflameis cleanandbluein colourandwhentheairwhenthe airholeis notcompletelyopentheflameissooctyandyellowin COLOUR
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| 4566. |
In NaCl, Na^(+) ion has ___________ and Cl^(-) ion has __________ electron configurations |
| Answer» Solution :GROUP 1 - LI, NA, K have ONE electron in theiroutermost SHELL whereas F, Cl, Br have 7 electronsin their outermost shell. | |
| 4567. |
Let us consider the following two reaction. 2NaCl_((aq))+F_(2(g))to2NaF_((aq))+Cl_(2(g))1^(st) reaction 2NaF_((aq))+Cl_(2(g))to2NaCl_((aq))+F_(2(g))2^(nd) reaction Which reaction will not occur .Why? |
| Answer» Solution :The FIRST involves the displacement of chlorine from NaCl,by fluorine .In the SECOND reaction chlorine displaces fluorine from NaF.Out of these two,the second reaction will not occur.Because fluorine is more active than chlorine and occupies the UPPER POSITION in the periodic table.So, in displacement reactions, the activity of the elements and their RELATIVE position in the periodic table are the key factors to determine the feasibility of the reactions.More active elements readily displace less active elements from their aqueous solutions. | |
| 4568. |
Lemon juice has a pH 2,what is the concentration of H^(+) ions? |
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Answer» SOLUTION :`[H^(+)]=10^(-PH)` `[H^(+)]=10^(-2)` `[H^(+)]=1xx10^(-2)M` |
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| 4569. |
Leave the test tubes undisturbed for some time and observe. Does the oil layer separate out? In which test tube does this happen first? |
| Answer» SOLUTION :In TEST tube A, two separate layers of oil and WATER are formed, while, in test tube B separate layers are not formed. | |
| 4570. |
Lead nitrate on heating gives lead oxide, nitrogen oxide and oxygen. Write balanced equation with state symbols for this reaction. |
| Answer» Solution :`2PB(NO_(3))_(2)(s)overset("HEAT")(to)2PbO(s)+4NO_(2)(g)+O_(2)(g)` | |
| 4571. |
Lead and mercury are comparatively poor conductors of heat. |
| Answer» Solution :True - Mercury, not being a GOOD conductor of HEAT is still USED in thermometers because it is a LIQUID at room temperature. | |
| 4574. |
Law of Conservation of Mass was given by? |
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Answer» Proust |
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| 4575. |
Lattice energies of fluorid, chloride, bromide and iodide compounds are 766.5, 597.5, 537.5 and 437.03 k J/mol, respectively. Compare the oxidizing capacities of the halogens on the basis of thelattice energies of these compounds with an appropriate reason. |
| Answer» Solution :The more the lattice energy, the stronger the ionic bond which in turn depends on the ease of formation of anion if the cation is the same. The easier the formation of the anion, the more the OXIDIZING capacity. Hence, from the given lattice energies it can be CONCLUDED that the increasing order of the oxidizing capacities of HALOGENS is <BR>`I_(2)lt Br_(2) lt Cl_(2) lt F_(2)` | |
| 4577. |
Lanthanides : Ce to Lu :: Actinides: ___________ |
| Answer» SOLUTION :TH to Lr - Ce to Lu are CALLED Lathanides and Thto Lr are called ACTINIDES. | |
| 4579. |
Lanthanides amd actinides are called as …… |
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Answer» ALKALI METAL |
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| 4580. |
Lanthanide Series |
| Answer» SOLUTION :The series of FOURTEEN elements from Cerium [CE(58)] to Lutetium [Lu (71)] is CALLED LanthanidesSeries. | |
| 4581. |
Lack of oxygen in muscles often leads to cramps among cricketers. This results due to |
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Answer» Conversion of PYRUVATE to ethanol |
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| 4583. |
KMnO_(4)+H_(2)SO_(4) + FeSO_(4) to K_(2)SO_(4) + MnSO_(4)+Fe_(2)(SO_(4))_(3)+H_(2)o Coefficients of sulphuric acid and ferric sulphate in thebalanced equation of above reaction are __________ and __________ , respectively |
| Answer» Solution :`2KMnO_(4)+8H_(2)SO_(4)+10FeSO_(4) to 5Fe_(2)(SO_(4))_(3)+ K_(2)SO_(4) +2MnSO_(4) + 8H_(2)O` | |
| 4584. |
KI and Pb(NO_(3))_(2) solutions are mixed to give a precipitate.What is the colour of the precipitate? |
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Answer» White |
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| 4586. |
K_(c)changes with change in_______. |
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| 4587. |
K_(2)SO_(4).Al_(2) (SO_(4))_(3) 24H_(2)O gives reactions of both K^(+) and Al^(+3) ions respectively |
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| 4588. |
Justify the following statements with an explanation. (i) Solubility of calcium oxide decreases with increase in temperature.(ii) What happens to the solubility in exothermic process with regard to temperature?(iii) In endothermic process, solubility increases with increase in temperature. (iv) At a given temperature, increase in pressure increases the solubility of the gas |
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Answer» Solution : (i) In an exothermic process, the solubility DECREASES. When CALCIUM oxide dissolves in water, exothermic reaction take place, and so the solubility of calcium oxide decreases. (ii) In an exothermic process, the solubility decreases with the increase in temperature, as there is already evolution of HEAT and it is observed. (iii) In an ENDOTHERMIC process, the solubility INCREASES. The solubility of `KNO_3` in water is an endothermic reaction and so solubility increases with the increase of temperature. (iv) At a given temperature, increase in pressure increases the solubility of gas according to Henry.s law. e.g. (`CO_2` in soft drinks) |
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| 4589. |
Justify the following statements: a) Cations are smaller in size than the corresponding atom. b) Size of the atom increases as we move down a group. c) Atomic size decreases as we move across a period. |
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Answer» Solution :a) Cations WOULD have lost outermost-shell electrons and HENCE their size is smaller than the corresponding atom. B] Addition of new shells, going down a group, increases the distance between the outermost electrons and the nucleus. c] Increase in nuclear CHARGE, tending to pull electrons closer to the nucleus, reduces the ATOMIC size of elements, along a period. |
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| 4590. |
Justify that HCOOH and CH_3 COOHare homologues. |
| Answer» SOLUTION :Because HCOOH and CH COOH differ by one `-CH_2` UNIT. | |
| 4591. |
Justify that C_2H_4 and C_3H_6are homologues of one another. |
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Answer» SOLUTION :Both the MOLECULES DIFFER by `-CH_2` UNIT. That is, `C_2H_4 + CH_2 to C_3H_6` `C_3H_6 - CH_2to C_2H_4` THEREFORE, `C_2H_4` and `C_3H_6`are homologues of each other. |
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| 4592. |
Just like H_(2)O, there are two lone pairs in Cl_(2)O molecule. But bond angle in Cl_(2)O is 111^(@). Explain. |
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Answer» Solution :(i) COMPARISON of electrons present in the valence shell in CL in `Cl_(2)O` and H in `H_(2)O` (ii) comparisons of size between chlorine and hydrogen (III) comparison of the valence electronic configuration between hydrogen and chlorine |
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| 4593. |
Jusitfy with the help of an example that displacement reaction is also a redox reaction. |
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Answer» SOLUTION :Consider the following displacement reaction in which Fe displaces CU from `CuSO_(4)` to form `FeSO_(4)`: `underset("Iron")(Fe(s))+underset(("Blue"))underset("Copper sulphate")(CuSO_(4)(aq))rarrunderset(("Green"))underset("Iron (II) sulphate")(FeSO_(4)(aq))+underset(("Reddish-brown"))underset("Copper")(Cu(s))` In the above reaction, Fe is gaining oxygen. HENCE, Fe is oxidised. `CuSO_(4)` is loosing oxygen. Hence, it is reduced. So, it is a redox reaction. |
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| 4594. |
J-shped tube closed at one end was used by Boyle to study the relationship between the pressure of the trapped gas and its volume. Such a set up is given here. Initially some amount of gas is taken in the tube and mercury is poured in it. The volume of the gas is 0.2 L and the difference in the height of themercury column is 760 mm of Hg. Now, some more amount of mercury is poured and the difference in the height of themercury column is found to be 1140 mm of Hg. Calculate the new volume of the gas considering the temperature constant. |
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Answer» Solution :`V_(1) = 0.2 LV_(2)` =? `P_(1) = 760 "mm "P_(2) = 1140" mm "+ 760` mm ACCORDING to Boyle's LAW ` P_(1) V_(1) = P_(2) V_(2)` ` 1520 xx 0.2 = 1900 xx V_(2) rArr V_(2) = (1520 xx 0.2)/(1900) = 0.16 `L |
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| 4595. |
IUPAC stand for International Union of Pure and Analytical Chemistry. |
| Answer» Solution :IUPAC STAND for INTERNATIONAL Union of PURE and APPLIED CHEMISTRY. | |
| 4596. |
IUPAC name of CH_(3)-overset(CH_(3))overset(|)(CH)-CH_(2)-CH_(2)-CH_(3) is…………………. |
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Answer» pentane |
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| 4597. |
IUCN is an international agency to protect threatened animals and plants. |
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| 4599. |
It is the electrode at which oxidation takes place in an electrolytic cell . |
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| 4600. |
It is the discharge of a catin at cathode . |
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