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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.
| 6451. |
Does entropy increase or decrease when egg is boiled? |
| Answer» Solution :On boiling EGG, entropy decreases as DUE to DENATURATION, the helical structure of PROTEIN become more complicated and random coiled structure. | |
| 6453. |
Does conservation mean to protect something harmful to human population ? |
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| 6454. |
What happens when a solution of an acid is mixed with a solution of a base in a test tube ? (i) The temperature of the solution increases (ii) The temperature of the solution decreases (iii) The temperature of the solution remains the same (iv) Salt formation takes place |
| Answer» Solution :YES, HEAT is releasedSo , the temperature of the MIXTURE , increases. | |
| 6455. |
Does a balanced chemical equation satisfy the law of conservation of mass ? |
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| 6457. |
Dobereiner's triads could not arrange all the elements known at that time. |
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Answer» Solution :In Dobereiner.s triads, three elements were arranged in the ORDER of increasing atomic masses of elements in which the atomic mass of the MIDDLE element is the average of the atomic masses of the other two elements. Dobereiner could IDENTIFY triads from the elements known at that time was only a COINCIDENCE. Thus, this CLASSIFICATION of elements into triads could not be applied to all the elements known at that time. |
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| 6458. |
Dobereiner's Triad |
| Answer» SOLUTION :When elements with SIMILAR chemical properties are arranged in increasing order of their atomic mass in group of three CALLED as TRIADS, the atomic mass of the MIDDLE element is approximately equal to the mean of the atomic masses of the other two elements. | |
| 6459. |
Dobereiner: Triad :: Newlands : __________ |
| Answer» Solution :Octaves - Doberiner ARRANGED three elements in atriad whereas Newlands ARRANG e d the elementsin increasing ORDER of their ATOMIC MASSES. Hefound that fir stelement and tlw eighth elementhad similar properties and calledit law of octaves. | |
| 6460. |
Do they contain the same number of shells? |
| Answer» SOLUTION :These ELEMENTS CONTAIN the same number of SHELLS (2, K and L). | |
| 6461. |
do theycontainthe samenumberof shells ? |
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Answer» SOLUTION :YES Alltheseelementscontainthe samenumberofshellsI.e.,TWOSHELLS- KandL In ferencefromtheisacitvity, welearnthat theinaperiodall elementhavesamenumberof shellsbutnotsamenumberofvalenceelectrons.Aswe moredownwardsin a periodthenumberof valenceelectronsincreases by ONE |
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| 6462. |
Do these elements also contain the same number of valence electrons Li , Na , Mg ? |
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Answer» Solution :No, all these elements contain DIFFERENT number of valence electrons. 3] Do they contain the same number of shells? ANSWER: Yes. All these elements contain the same number of shells, i.e., TWO shells - Kand L. Inference: From this activity, we learn that the in a period, all elements have same number of shells but not same number of valence electrons. As we move DOWNWARDS in a period, the number of valence electrons increases by one. |
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| 6463. |
Do these elements also contain the same number of valence electrons ? |
| Answer» Solution :These ELEMENTS do not contain the same NUMBER of VALENCE ELECTRONS. | |
| 6465. |
Do the covalent compounds conduct electricity ? |
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| 6466. |
Do plants grow better when the soil is highly acidic ? |
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| 6467. |
Do ionic componds have low boiling points ? |
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| 6468. |
Do equimolar solutions of NaOH and Ca(OH)_(2) possess same pH value at the same temperautre ? Justify |
| Answer» Solution :Sodium HYDROXIDE being a STRONG base than calcium hydroxide FURNISHES more number of `OH^(-)` as it UNDERGOES complete DISSOCIATION. Greater the `OH^(-)` concentration greater will be the basic character. A stronger base will have pH value greater than a weak base. Hence NaOH, which is a strong base has higher pH value than `Ca(OH)_(2)` | |
| 6469. |
Do both test tubes have the same amount of foam ? |
| Answer» Solution :Both the TEST tubes do not contain the same amount of foam. The test TUBE with SOAP solution CONTAINS little foam in it. | |
| 6470. |
Do basic solutions also have H^+ (aq) ions ? If yes, then why are these basic ? |
| Answer» Solution :ACID and basic SOLUTIONS both have `H^+` (aq) ions. The DIFFERENCE is that in ACIDS `H^+` (aq) ion concentration is more than `OH^-` (aq) ion concentration while in basic solution `OH^-` (aq) ion concentration is more than `H^+` (aq) concentration. | |
| 6471. |
Do basic solution also have H^(+) (aq) ions ? If yes, then why are these basic ? |
| Answer» Solution :BASIC solutions ALSO have `H^(+)` ions in addition to `OH^(+)` ions . They are basic because in these solutions , `OH^(-)` ION concentration is greater than `H^(+)` ion concentration . | |
| 6472. |
Do basic solutions also have H^(+) aq ion ? If yes, then why are these basic ? |
| Answer» Solution :When a BASE DISSOLVES in water, it will produce `H^(+)` ions as well as `OH^(-)` ions. The `H^(+)` ion CONCENTRATION is LESS than `OH^(-)` ion. Hence they are basic. | |
| 6474. |
Do all the single electron species of various ele- ments possess same energy for the electron in the ground state? Give reason. |
| Answer» Solution :reason for REVOLUTION of ELECTRON around the NUCLEUS. | |
| 6475. |
Do antioxidants behave as reducing agents ? |
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| 6476. |
Do acidic solutions contain OH^(-) ions ? |
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| 6477. |
Distinguish between the saturated and unsaturated solution at a temperature of 25^@ C using the data given below (Note : Solubility of NaCl is 36g) . (i) 16g NaCl in 100g water, (ii) 36g NaCl in 100g water. |
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Answer» SOLUTION :Solubility of NaCl is 36g. (i) 16G NaCl in 100G water is an unsaturated solution. (ii) 36g NaCl in 100g water is a saturated solution. 
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| 6478. |
Distinguish between roasting and calcination . Which of these two is used for sulphide ores and why? |
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Answer» Solution :Roasting: It is the process in which sulphide ores of the metals are converted into oxides by heating them in the presence of excess AIR, For example zinc sulphide is converted into zinc oxide by roasting. `2ZnS(s)+3O_2(g) to_(Roas ti ng)^(Heat) 2ZnO(s)+2SO_2(g)` Calcination: It is the process in which carbonates ores of the metals are decomposed into oxides by heating them in the absence or limited air. For example, zinc CARBONATE is decomposed into zinc oxide and carbon dioxide by calcination. `ZnCO_3(s)to_(calci NATION)^(Heat)ZnO(s)+CO_2(g)` Out of roasting and calcination, only roasting is used for sulphide ores. This is because it is EASIER to obtain metal from its oxide as compared to its sulphide. |
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| 6479. |
Distinguish between renewable and non-renewable sources of energy, |
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Answer» Solution :Renewable SOURCE * The SOURCES of energy which can never be finished and are continuously PRODUCED in nature are known as renewable sources of energy EX: wind, the sun, biogas, hydropower etc. Non-renewable sources * The sources of energy which are exahaustable and take lots of time to be formed again are known as non-renewable source of energy For ex: coal, natural GAS petroleum etc.a |
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| 6480. |
Distinguish between : Oxidation reaction and Reduction reaction |
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| 6481. |
Distinguish between orbit and orbital with respect to defination |
| Answer» Solution :`{:("ORBIT","Orbital"),("Orbital is a definite circular PATH in which electrons revolve AROUND the nucleus.","Orbital is the three-dimensional SPACE around the nucleus in which the probability of finding an electrons with a particular energy is MAXIMUM."):} ` | |
| 6482. |
Distinguish between Metals and non-metals on the basis of their physical properties. |
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| 6483. |
Distinguish between metal and non-metal on the basis of their chemical properties. |
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| 6484. |
Distinguish between ionic and covalent compounds under the following properties: (a) Strength of forces between constituent elements (ii) Solubility of compounds in water (c ) Electrical conduction in substances |
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Answer» Solution :(a) Ionic compounds have strong force of attraction between the oppositely charged IONS(e.g `Na^+ and Cl^(-))`, so they are solids . Covalent compounds have weak force of attractio between their MOLECULES so they are USUALLY liquids or gases. (B) IOnic compounds are soluble in water but covalent compounds are INSOLUBLE in water. (c ) Ionic compounds conduct electricity when dissolved in water or when melted because they contains they (charged particles) But covalent, compounds like glucose do not conduct electricity because they do not contain ions. |
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| 6485. |
Distinguish between isotopes and isobars. |
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| 6486. |
Distinguish between homologus organs and analogus organs. In which catagory would you place wings of a bird and wings of a bat? Justify your answer giving a suitable reason. |
Answer» Solution : Wings of bird and wings of a bat are analogous ORGANS as they have DIFFERENT basic STRUCTURAL design but have SIMILAR appearance and PERFORM similar functions. |
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| 6487. |
Distinguish between : Endothermic reaction and Exothermic reaction |
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| 6488. |
Distinguish between electrochemical equivalent and equivalent mass of a substance |
| Answer» Solution :ELECTROCHEMICAL EQUIVALENT is the AMOUNT of substance deposited or liberated at the electrode by the passage of one coulomb of electricity through the electrolyte. Equivalent mass is the amount of substance deposited or liberated at the electrode by the passage of 1 Farady (96,500 C) of electricity through the electrolyte | |
| 6489. |
Distinguish between calcination and roasting |
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| 6490. |
Distinguish between : (3) Saturated carbon compounds and Unsaturated carbon compounds |
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| 6491. |
Distinguish between : (2) Diamond and Graphite |
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| 6492. |
Distinguish between : (1) Ionic compounds and Covalent compounds |
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| 6494. |
Dissolving 120 g of urea ( Molar mass of urea = 60" g mol"^(-1) ) in 1000 of water gave a solutionof density 1.15 g/mL. Calculate the molarity of the solution. |
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| 6495. |
Dissolution of acid or base in water is |
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Answer» Exothermic |
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| 6497. |
Disodium potassium phosphate is a/an ____salt |
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Answer» acid |
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| 6498. |
Discuss the magnetic separation methods. |
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Answer» Solution : Magnetic separation method: Priciple : The magnetic properties of the ores form the basis PF separation . When either the ORE or the gangue is megnetic . This method is employede.g Tinstone `SnO_(2)`, the ore of TIN . Method :The crushed ore is placed overe a conveyer belt which rotates around two metal wheels , one of which rotated to the magnetic wheel and fall sepratately APART from the nonmagnetic PARTICLES . 
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| 6499. |
Discuss the important physical and chemical properties of alcohols. Give the tests of alcohols. |
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Answer» Solution :Properties of alcohols (A) Physicial properties 1. The lower members of alcohols are colourless, volatile liquids having typical alcoholic smell and burning taste. 2. Lower alcohols are completely soluble in water. However, the solubility decreases with increase in molecular mass. 3. The boilng points of alcohols are higher than those of alkanes of comparable molecular masses. 4. The common alcohols are lighter than water. B. Chemical Properties. 1. Action with sodium. Alcohols react with sodium metal to form sodium alkoxide and hydrogen GAS is liberated. For example, `underset("Methanol")(2CH_(3)OH) + 2Na rarr underset("Sodium methoxide")(2CH_(3)ONa) + H_(2)` `underset("Ethanol")(2C_(2)H_(5)OH) + 2Na rarr underset("Sodium ethoxide")(2C_(2)H_(5)ONa) + H_(2)` 2.Combustion. Alcohols burns readily in air and produce carbon dioxide, water and heat. For example. `underset("Methanol")(CH_(3)OH) + O_(2) rarr CO_(2) + 2H_(2)O + "Heat"` `underset("Ethanol")(C_(2)H_(5)OH) + 3O_(2) rarr 2CO_(2) + 3H_(2)O + "Heat"` 3. Oxidation. Alcohols are easily oxidised to corresponding carboxylic acids by oxidising agents such asacidified potassium dichromate. For example, `underset("Methanol")(CH_(3)OH) + 2[O] overset(K_(2)Cr_(2)O_(7), H_(2)SO_(4))rarr underset("Methanoic acid")(HCOOH) + H_(2)O` `C_(2)H_(5)OH + 2[O] overset(K_(2)Cr_(2)O_(7), H_(2)SO_(4))rarr underset("Ethanoic acid")(CH_(3)COOH) + H_(2)O` During this reaction, the organge COLOUR of `K_(2)Cr_(2)O_(7)` changes to green. 4. Reaction with carboxylic acids (esterification). Alcohols react with carboxylic acids in the presence of concentration sulphuric acid as catalyst to form ester which have sweet fruit smell. This reaction is called esterification. For example : `underset("Methanol")(CH_(3)OH) + underset("Ethanoic acid")(CH_(3)COOH) underset("Heat")overset("Conc. " H_(2)SO_(4))hArr underset("Methyl ethanoate")(CH_(3)COOCH_(3)) + H_(2)O` `underset("Ethanol")(CH_(3)CH_(2)OH) + underset("Ethanoic acid")(CH_(3)COOH) underset("Heat")overset("Conc. " H_(2)SO_(4))hArr underset("Ethyl ethanoate")(CH_(3)COOC_(2)H_(5)) + H_(2)O` Tests for Alcohols. The presence of an alcoholic group or hydroxyl group in an organic compound can be tested by the following tests : 1. Sodium metal test. Add a small piece of sodium metal of the organic compound in a dry test tube. If the bubbles of hydrogen gas are produced, it shows the presence of alcoholic group (-OH) in the organic compound. 2. Ester formation test. Warm the organic compound with ACETIC acid and a few drops of conc. `H_(2)SO_(4)`. A sweet smell (due to the formation of ester) indicates the presencce of alcohlolic group. |
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| 6500. |
Discuss the important properties of ionic compounds. |
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Answer» Solution :Important properties of ionic compounds. The important properties of the ionic or electrovalent compounds are GIVEN below : 1. Ionic compounds consist of ions. The ionic compounds consist of positive ions or cations and negative ions or anions. These ions are attracted towards each other by force of attraction called electrostatic force of attraction. 2. Ionic compounds are crystalline SOLIDS. The ionic compounds exist as solids. These solids are in the form of crystals. The crystals are formed by the combination of a large number of cations and anions. For example, sodium chloride is made up by `Na^(+)andCl^(-)` ions. The arrangement of ions in the crystals is called crystal lattice. The crystal lattice is different for different ionic compounds. The arrangement of `Na^(+)andCl^(-)` ions in the crystal lattice of NaCl is as shown. 3. Ionic compound have high melting and boiling points. We know that the ionic compounds are solids in which a large number of cations and anions are closely packed in space. If these compounds are to melt or boil, the ions are to be separated from each other. For the separation of ions, energy is needed. Therefore, ionic compounds have high melting and boiling points. 4. Ionic compounds do not conduct electricity in the solid state. In ionic compounds, the current is to be carried by the movement of cations and anions. As these are closely packed in the crystalline solids, their movement is almost nil. Since the ions are not in a position to move, the ionic compounds are not conducting in the solid state. 5. Ionic compounds conduct electricity in molten state or in solution. When heated, the ionic compounds melt. SIMILARLY, when added to a solvent, the cations and anions are free to move. Because of the movement of the ions, these compounds conduct electricity. 6. Ionic compounds are generally SOLUBLE in water. When an ionic compound is added to water, the force which binds the ions with one another becomes weak. Therefore, these oppositely charged ions get separated and dissolve in water. 7. Ionic compounds have high dendities. 8. Ionic compounds are hard and brittle. 9. Ionic compounds undergo ionic reactions which are quick and proceed to COMPLETION. |
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