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.
| 501. |
Write the chemical equations for the Ethene to ethane conversion |
| Answer» SOLUTION :`H_2C = CH_2 OVERSET(H_2)(to) H_3C - CH_3` | |
| 502. |
Which of the following contains the largest number of molecules? |
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Answer» 0.2 mole of `H_2` `=0.2 xx 6.02 xx 10^23` `= 1.204 xx 10^23` molecules of `H_2` (II) 8.0 g `H_2 = (8.0)/(2) = 4.0` mole `H_2` ` = 4.0 xx 6.02 xx 10^23= 2.408 xx 10^24` molecules of `H_2` (iii) 17.0 g `H_2O = 17/18` MOLES of `H_2O` ` = 17/18 xx 6.02 xx 10^23` `= 5.685 xx 10^23` molecules of `H_2O` (IV) 6.0g of `CO_2 = (6.0)/(44)` moles of `CO_2` ` = (6.0)/(44) xx 6.02 xx 10^23` ` = 8.21 xx 10^22` molecules of `CO_@` |
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| 504. |
What is alkali? Give two example. |
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Answer» Solution :A base which is SOLUBLE in water is known as ALKALI. EXAMPLE: `NaOH,KOH` |
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| 505. |
Which metals do not liberate gas on reaction with acids? |
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Answer» ZN,Mg |
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| 506. |
Which of the following statements are correct for modern periodic table ? |
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Answer» New elements can be easily arranged. |
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| 509. |
The use of nonbiodegradable substances should be avoided. |
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Answer» |
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| 510. |
While cooking, if the bottom of the vessel is getting blackened on the outside, it means that |
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Answer» The FOOD is not COOKED COMPLETELY |
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| 511. |
Write the equations for the reaction of ethyne with hydrogen |
| Answer» SOLUTION :`HC -= CH OVERSET(H_2)(to) H_2C = CH_2 overset(H_2)(to) H_3C - CH_3` | |
| 512. |
What type of reaction occurs between ethene and hydrogen? |
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Answer» ADDITION is an example of addition reaction. |
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| 513. |
Which category of compounds is formed when one hydrogen atom of an alkane molecule is replaced by a hydroxyl group ? Name the functional groups in the following compounds: (a) RCOOH(b) RCOOR |
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Answer» SOLUTION :ALCOHOLS. a] Carboxylic acids. `""` B] ESTERS. |
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| 514. |
What are Electrolytic decomposition reactions? |
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Answer» Solution :In this TYPE of reaction,the reactant is decomposed by applying electricity. For example,decoposition of sodium chloride OCCURS on passing electric current through its aqueous solution . `2NaCl_((aq))OVERSET("Electricity")to2Na_((s))+Cl_(2(g))` |
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| 515. |
What is meant by 22 carat gold in terms of percentage purity? |
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Answer» Solution :24 carat gold is CONSIDERED to have 999.99 parts of gold per 1000 g. THEREFORE, one carat is taken as one part of 24. That means 22 carat gold is 22 parts per 24 parts. Accordingly, parts of gold in 1000 g of 22 carat gold can be calculated. From this, percentage can be FOUND out. Amount of gold in 1000 g of 22 carat gold= `22/24 xx 1000 =916.3` g Percentage of gold= 91.6%. |
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| 517. |
What happens when chlorine gas is passed into and aqueous solution of potassium iodate ? |
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Answer» SOLUTION :Since chlorine is more REACTIVE than IODINE, the latter is dislpaced from POTASSIUM iodile by chlorine. `2KI + CI_(2) to 2KCI +I_(2)` |
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| 518. |
Which one of the following elements exhibit maximum number of valence electrons? |
| Answer» Solution :Phosphorus which belongs to Group 15 has 5 i.e., MAXIMUM number of electrons. | |
| 519. |
The symbols are used in a chemical reaction to |
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Answer» MAKE the equation LOOK nice |
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| 520. |
What are Metalloids ? Give examples ? |
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Answer» Solution :There are some meals which show some properties of a METALS and NON metals. Such ELEMETNS are CALLED METALLOIDS. Eg. Germanium, Silicon, Arsenic. |
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| 521. |
Which one will migrate towards anode in an electrolytic cell ? |
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Answer» Lead ION |
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| 522. |
Which functional groups always occur at the terminal position of a carbon chain? |
| Answer» Solution :Aldehydic GROUP R-CHO and carboxyl group R-COOH (R = ALKYL group). | |
| 523. |
Write two tests to demonstrate that CH_3COOH is an acid. |
| Answer» SOLUTION :`CH_3COOH`turns BLUE litmus red and LIBERATES carbon DIOXIDE from sodium BICARBONATE. | |
| 524. |
What is anode mud ? |
| Answer» Solution :When electriccurrent in passed through the electrolyticsolution , PURE coppergets deposited at the cathode and the impuritiessettleat the BOTTOM of the anode in the FORM of sludge CALLED anode MUD . | |
| 525. |
Which kind of defect is found in KCl crystal ? |
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Answer» Frenkel |
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| 526. |
Zinc piece and zinc powder are taken in two test tubes and equal amount of dil. HCl is added. In which test tube does the reaction proceed faster? |
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Answer» |
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| 527. |
Which non metalic element is in liquid form. |
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Answer» Carbon |
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| 528. |
What do you observe ? |
| Answer» Solution :When sodium CARBONATE is added to 2 mL dilute solution of ethanoic ACID, a brisk effervescence appear DUE to EVOLUTION of carbon dioxide gas. | |
| 529. |
What will be the mass of one ""^(12)C atom in g? |
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Answer» SOLUTION :`"1 mole of " ""^(12)C" atoms"=6.022xx10^(23)" atoms"=12g` `"Thus, "6.022xx10^(23)" atoms of """^(12)" have mass "=12g` `therefore" 1 atom of " ""^(12)C" will have mass"=(12)/(6.022xx10^(23))G=1.9927xx10^(-23)g` |
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| 530. |
Write the equations for the reaction of ethyne with chlorine |
| Answer» Solution :`HC -= CH overset(Cl_2)(to) CLHC = CHCL overset(Cl_2)(to) Cl_2HC - CHCl_2` | |
| 531. |
Which gas is usually liberated when an acid reacts with a metal ? Illustrate with an example. How will you test for the presence of this gas? |
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Answer» Solution :Usually hydrogen gas is liberated when an acid reacts with a METAL. This is illustrated by taking examples of zinc and iron metals. `Zn(s)+2HCl(aq) rarr ZnCl_(2) + H_(2)(G)` `Fe(s) + H_(2)SO_(4)(aq) rarr FeSO_(4)(aq) + H_(2)(g)` Test for Hydrogen gas Hydrogen gas burns with a POP sound. It is lighter than air. When hydrogen gas is passed through soap solution, soap bubbles are formed which being lighter than air rise up. The pop sound is due to the combustion of hydrogen producing water. `2H_(2)+O_(2) rarr 2H_(2)O` |
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| 532. |
When an organic compound X is warmed with alkaline solution of KMnO_4a new compound Y is formed which smells of vinegar. On heating compounds X and Y with a few drops of concentrated sulphuric acid another compound Z is formed. Name thecompound X and Y |
| Answer» SOLUTION : X = ETHANOL, Y = ETHANOIC ACID | |
| 533. |
When an organic compound X is warmed with alkaline solution of KMnO_4a new compound Y is formed which smells of vinegar. On heating compounds X and Y with a few drops of concentrated sulphuric acid another compound Z is formed. Name the compound Z |
| Answer» SOLUTION : ETHYL ethanoate | |
| 534. |
When an organic compound X is warmed with alkaline solution of KMnO_4a new compound Y is formed which smells of vinegar. On heating compounds X and Y with a few drops of concentrated sulphuric acid another compound Z is formed. Name the process of conversion of X to Y |
| Answer» SOLUTION :OXIDATION | |
| 535. |
When an organic compound X is warmed with alkaline solution of KMnO_4a new compound Y is formed which smells of vinegar. On heating compounds X and Y with a few drops of concentrated sulphuric acid another compound Z is formed. Name the process of formation of Z |
| Answer» SOLUTION :ESTERIFICATION | |
| 536. |
Write the balanced equation for the following chemical reactions: (i) Hydrogen + Chlorine rarr Hydrogen chloride (ii) Barium chloride + Aluminium sulphate rarr Barium sulphate + Aluminium chloride (iii) Sodium + Water rarr Sodium hyddroxide + Hydrogen |
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Answer» SOLUTION :(i) `H_(2)(G)+Cl_(2)(g)rarr2HCl(g)` (ii) `3BaCl_(2)(aq)+Al_(2)(SO_(4))_(3)(aq)rarr3BaSO_(4)(s)+2AlCl_(3)(aq)` (iii) `2Na(s)+2H_(2)O(l)rarr2NaOH(aq)+H_(2)(g)` |
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| 537. |
What is thermite reaction? |
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Answer» Solution :Reduction of iron OXIDE to iron by aluminium is CALLED thermite reaction. `Fe_(2)O_(3) + 2AL rarr 2Fe + Al_(2)O_(3) + "Heat"`. |
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| 538. |
Which coating is used on electric wire ? |
| Answer» SOLUTION :The coating of POLYVINYL CHLORIDE is FORMED on electric WIRE. | |
| 539. |
When calciumcarbonateis heated, itbreaksdowninto______ and_________. |
| Answer» SOLUTION :CALCIUMOXIDE , CARBONDIOXIDE | |
| 540. |
Which reagent does not react with iron ? J |
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Answer» CONC. `HNO_(3)` |
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| 541. |
Which of the following acids is present in vinegar? |
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Answer» LACTIC ACID |
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| 542. |
Write the limitations of Mendeleev's classification. |
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Answer» Solution :The limitations of Mendeleev.s classification of elements are as follows: (1) Position of HYDROGEN in periodic table : Electronic configuration of hydrogen resembles with alkali METALS. Like alkali metals, hydrogen combines with halogens, oxygen and sulphur to form compounds having similar formulae. For example,  Hence, many PROPERTIES of hydrogen are similar to those of alkali metals, so it should be placed along with alkali metals of group IA. Just like halogens `(F_(2),Cl_(2),Br_(2),I_(2))`, hydrogen also exists as a diatomic molecule `(H_(2))`. Hydrogen combines with metals and non-metals to form covalent compounds.  Therefore, many properties of hydrogen are similar to those of halogens, hence it can be placed in halogen group. In short, position of hydrogen in the periodic table is a matter of controversy. ( 2 ) Position of isotopes : Isotopes were discovered long after Mendeleev gave his periodic classification of elements. Isotopes : Atoms of the same element having same atomic number but different atomic masses are known as isotopes. Isotopes of any element have similar chemical properties, but different atomic masses. Thus, isotopes of all elements posed a challenge to Mendeleev.s periodic table. Therefore, the placing of isotopes in distinguishable positions in the periodic table BECOME almost impossible. (3) Irregularities of atomic masses of elements : Atomic masses do not increase in a regular manner in moving from one element to NEXT element. So it was difficult to predict that how many element would be discovered between two elements. |
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| 543. |
Write the atomic numbers of two elements X and Y having electronic configuration 2, 8, 2 and 2, 8, 6 respectively. |
| Answer» Solution :ATOMIC NUMBER of `X = 2 + 8 + 2 = 12`, atomic number of `Y = 2 + 8 + 6 = 16.` | |
| 544. |
What is the trend in the atomic size in a group, does it increase or decrease? |
| Answer» SOLUTION :INCREASE | |
| 545. |
Which of the following is a displacement reaction? |
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Answer» `NaOH + HNO_(3) to NaNO_(3) + H_(2)O` |
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| 546. |
What are electropositive atoms? How does electropositivity vary along the period in modern periodic table ? |
| Answer» SOLUTION :Atoms which GIVE up electrons to form cations are called ELECTROPOSITIVE atoms. Decreases while GOING from LEFT to right. | |
| 547. |
Which of the following is not half metal. |
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Answer» Silicon |
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| 548. |
Which one of the following is a hetero diatomic molecules? |
| Answer» SOLUTION :`HI` | |
| 549. |
What will happen if a blue litmus paper is brought in contact with an aqeous solution of sulphur dioxide ? |
| Answer» SOLUTION :BLUE litmuspaper will TRUN RED . | |