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.
| 51. |
Which of the following elements is a semi metal. |
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Answer» Aluminum |
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| 52. |
Which of the following statemetns is (are) correct about the reaction between sulphur and concentrated sulphuric acid ? |
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Answer» `SO_(2)` gas is FORMED |
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| 53. |
Two rows shown separately at the bottom of the Modern Periodictable are called __________ and _________ . |
| Answer» SOLUTION :LANTHANIDE SERIES,ACTINIDE series | |
| 54. |
Which of the following represents the formulaof blue vitriol ? |
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Answer» `ZnSO_(4)` |
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| 55. |
Why are unsaturated hydrocarbons more reactive than saturated hydrocarbons? |
| Answer» Solution :Unsaturated hydrocarbons are more REACTIVE due to presence of C=C and C=C bonds which are WEAKER than the SINGLE bond in SATURATED hydrocarbons. These double and triple bonds are the reactive sites in the unsaturated hydrocarbons which easily GIVE addition reactions. | |
| 56. |
Which of the following is a (are) combination reaction (s) ? |
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Answer» `CaO + H_(2)O to Ca(OH)_(2)` |
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| 57. |
Write the balanced chmical equation for the following reaction and identify the type of reaction in each case Thermite reaction, Iron (III) oxide reacts with aluminium and gives molten iron and aluminium oxide. |
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Answer» Solution :Balanced equation is : `Fe_(2)O_(3)(s)+2Al(s)toAl_(2)O_(3)(s)+2Fe(l)+"heat"` It is a displacement REACTION where aluminium displaces iron(Fe) from `Fe_(2)O_(3)`. Molten iron is USED for repairing broken RAILWAY tracks. |
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| 58. |
Think about it, Write the Electronic configuration and valency of first 20 elements. |
Answer» SOLUTION :
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| 60. |
What do you observe when electrolysis of copper sulphate is done using strip as anode ? Give reasons. |
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Answer» Solution :Electrolyte: `CuSO_(4)` `CuSO_(4) hArr Cu^(2+) + SO_(4)^(2-)` `{:("Cathode (reduction)","Anode (Fe) OXIDATION"),(Cu^(2+) + 2E^(-) rarr Cu,Fe - 2e^(-) rarr Fe^(2+)),(,"Compared to " SO_(4)^(2+)"," Fe " ionsies to give " Fe^(2+) " DUE to low reduction potential"):}` `:. Cu and Fe^(+2)` are PRODUCTS at cathode and anode, respectively. |
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| 61. |
Which of these are more reactive? |
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Answer» Hg |
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| 62. |
Write the structural formula of ethanol. |
| Answer» SOLUTION :`H-UNDERSET(H) underset(|) OVERSET(H) overset(|)C- underset(H)underset(|) overset(H) overset(|)C-OH` | |
| 63. |
Write the balanced chemical equation for the following reaction and identify the type of reaction and define it. Iron III oxide reacts with aluminium and gives molten iron and aluminium oxide'. |
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Answer» SOLUTION :`Fe_(2)O_(3)+2AlrarrAl_(2)O_(3)+2Fe` Displacement reaction is the reaction in which one elementdisplaces ANOTHER ELEMENT. |
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| 64. |
Write the chemical equation for the reaction which takes place during burning of ethanol in air. |
| Answer» SOLUTION :`CH_(3)CH_(2)OH + 3O_(2) rarr 2CO_(2) + CH_(2)O` | |
| 65. |
What are modern periodic table? |
| Answer» Solution : The modem periodic table is a TABULAR arrangement of elements in rows and columns, HIGHLIGHTING the regular repetition of PROPERTIES of the elements. | |
| 66. |
What are ill effects of drinking excess of alohol ? |
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Answer» Solution :III effects of drinking excess of ALCOHOL : (i) With increase in its consumption, the body loses its CONTROL and gradually one loses one.s consciousness. (ii) If consumed in large quantities, it may cause death by damaging liver. (iii) It CAUSES addiction and makes person dependent on it. (iv) medically, alcohol is an intoxicant. The person loses all sense of discrimination under its influence. Therefore, we should all condemn drinking of alcohol on any pretex because once started, it lead to a TOTAL disaster. |
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| 67. |
The relationship between volume and number of molecules of a gas at constant temperature and pressure is known as ........ |
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Answer» |
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| 68. |
What is denatured alcohol? |
| Answer» SOLUTION : A sample of ETHANOL containing some poisonous CHEMICALS such as methanol or acetone or pyridine or copper sulphate is called DENATURED SPIRIT. | |
| 69. |
When the temperature increases, volume percentage |
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Answer» INCREASES |
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| 70. |
Write the balanced chemical equation for the following chemical reactions. Ethene is burnt in the presence of oxygen to form carbon dioxide, water and releases heat and light. |
| Answer» SOLUTION :`C_(2)H_(4)(G)+3O_(2)(g)to2CO_(2)(g)+2H_(2)O(g)+"heat" +"LIGHT"`. | |
| 71. |
Which of the following substances can be obtained by using common salt as the raw material ? |
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Answer» CAUSTIC SODA |
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| 72. |
Which one of the following solutions with same concentrations will have lowest pH?NaHCO_(3) HCl KOH Na_(2)CO_(3) |
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Answer» `NaHCO_(3)` |
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| 73. |
Zinc, aluminium and iron give different products when reacted with sulphuric acid of different strengths (dilute and concentrated), whereas copper reacts only with concentrated sulpuric acid. Justify. |
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Answer» Solution :(i) Comparisonof REACTIVITY of Zn, Al, Fe and Cu. (ii) Comparison of OXIDATION potentials of zinc, iron, alumininum with hydrogen. (iii) TYPE of reaction that takes place when the above metals react with diluted `H_(2)SO_(4)`. (iv) Change in the proprety of `H_(2)SO_(4)` with the increase in CONCENTRATION. (v) Change in the product due to the change in the concentration. (vi) Comparison fo oxidation potential of copper with hydrogen. (vii) Tpye of reaction that can takes place between copper and concetrated `H_(2)SO_(4)` |
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| 74. |
There are two jars A and B containing food materials. Food in jar A is pickled with acetic acid while B is not. Food of which jar will stale first ? Explain. |
| Answer» Solution :FOOD in JAR B will stale FIRST | |
| 75. |
What are acidic and basic oxides? |
| Answer» Solution :OXIDES, which dissolved in WATER to form acids are acidic oxides. For EXAMPLE, `CO_2(g) + H_2O(l)toH_2CO_3(aq)`Oxides of non-METALLIC elements are acidic. Oxides, which dissolved in water to form BASES are basic oxides. For example, `Na_2O(s) + H_2O(l)to2NaOH(aq)`Oxides of metallic elements are basic | |
| 76. |
What is meant by allotropes ? |
| Answer» Solution :When an ELEMENT exists in TWO or more forms which have different PHYSICAL properties but same CHEMICAL properties are KNOWN as allotropes. | |
| 77. |
What would be the colour of litmus in a solution of sodium carbonate? |
| Answer» SOLUTION :The colour of LITMUS in a solution of SODIUM CARBONATE is blue. | |
| 78. |
Which of the following is temperature independent |
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Answer» Molality |
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| 79. |
What is an acid ? |
| Answer» SOLUTION :An acid is a solution that contains REPLACEABLE hydrogen ATOMS. | |
| 80. |
you aregiventhe followingmaterials 1.Marblechips2.Dilutehydrochloricacid 3.Zinc granules Identifythe typeof reactionwhenmarblechips andzincgranulesare addedseparatelyto acidand zinc granulesare addedseparatelyto acidtakenin twotubes . writechemicalequationsin eachcase . |
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Answer» Solution :1.Marblechips chipsreactwithdilutehydrochloricacidto formcalciumchloride and carbonicacid. Theacidchangesto `CO_(2) and H_2O`. Itisa doubledisplacement reaction . `CaCO_(3(s)) +2HCI_((AQ)) toCaCl_(2(aq)) + H_(2) CO_(3(aq))(CO_(2) H_(2) O)` |
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| 82. |
The volatile impurities associated with zinc spelter are ______. |
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Answer» CD and Fe |
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| 83. |
Write the different types of isotopes of oxygen and its percentage abundance. |
Answer» SOLUTION : `"The ATOMIC MASS of OXYGEN"=(15.9949xx0.99757)+(16.9991cc0.00038)+(17.9992xx0.00205)` `="15.999 AMU."` |
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| 84. |
Complete the following reaction :- (i) Cu + O_2 to(ii) Al_2O_3 +HCl to |
| Answer» | |
| 85. |
The slope obtained by drawing a tangent at time 't' on the curve for the concentration of reactants vstime is equal to instantaneous rate. |
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Answer» |
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| 86. |
Write the number of period the modern periodic table has. How do the valency and metallic character of elements vary on moving from left to right in a period ? How do the valency and atomic size of elements vary down a group ? |
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Answer» Solution :There are 7 horizontal rows known as periods, that the modern periodic table has. In periods, the number of valence electrons increases from left to right and due to decrease in atomic SIZE, the force of attraction between the valence electrons and the nucleus increases. Metallic character decreases along the period due to decrease in TENDENCY to LOSE electrons. Atomic size generally increases from top to bottom in a group due to the ADDITION of a NEW shell i.e., number of shells goes on increasing down the group. |
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| 87. |
What is 'Baking Powder ? How does it make the cake, soft and spongy ? |
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Answer» Solution :Baking POWDER is a mixture of baking soda and tartaric acid or CITRIC acid. When baking powder is heated, baking soda decomposes to give carbon dioxide and sodium carbonate. `CO_2`gas CAUSES breads and cakes to RISE and make it soft and spongy. Tartaric acid neutralises sodium carbonate. |
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| 88. |
The teacher wishes to show in laboratory that all the crystals will decompose to give water on heating, which is collected on the upper surface inside the test tube. Name any four compounds the teacher should use in the laboratory to perform this activity. |
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Answer» SOLUTION :The TEACHER can USE the following four COMPOUNDS : (1) Blue vitrol, i.e., Copper sulphate (Blue crystalline salt) ( 2) Green vitrol, i.e., Iron sulphate (Green crystalline salt) (3) Sodium carbonate (White coloured CRYSTALS) ( 4) Calcium sulphate (White coloured crystals) |
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| 90. |
Velocity of the electron in electron microscope is 1.6xx106m//s.What would be the wavelenght of the electron |
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Answer» `5.39 Å` `m=9.1xx10^(-31)KG` `lambda=h/(MV)= (6.625xx10^(-34))/(9.1xx10^(-31)xx1.6xx10)= 4.55Å` |
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| 91. |
What is the root word, if the compound has nine number of carbon atoms? |
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Answer» Meth- |
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| 92. |
Which of the following statements is incorrect? |
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Answer» Corrosion of copper TAKES PLACE by contact with air and water. |
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| 93. |
Two pairs of Dobereiner's triad. |
| Answer» SOLUTION :(i) Lithium (Li), Sodium (NA), Potassium (K)(ii) Chlorine (Cl), Bromine (Br), IODINE (I). | |
| 94. |
What happens when sodium chloride is dissolved in water ? |
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Answer» Solution :SODIUM CHLORIDE DISSOCIATES into ions . ` NaCI to Na^(+) CI^(-)` |
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| 95. |
Which of the following elements will form an acidic oxide? |
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Answer» An ELEMENT with ATOMIC NUMBER 7 |
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| 96. |
Which of the following statements is (are) wrong ? |
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Answer» Lime juice is acidic in nature. |
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| 97. |
What happens when magnesium ribbon burns in the presence of oxygen ? Write the balanced chemical equation. |
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Answer» Solution :Magnesium ribbon burns with a DAZZLING white FLAME when BURNT in the presence of oxygen. `2Mg(s)+O_(2)(g)to2MgO(s)`. |
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| 98. |
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid, whereas copper does not. Explain, why? |
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Answer» Solution :Zinc in above HYDROGEN whereas COPPER is below hydrogen in the activity series of metals. That is why zinc displaces hydrogen from dilute hydrochloric acid, while copper does not. `Zn+HClrarrZnCl_(2)+H_(2)` `Cu+HClrarr` No reaction |
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| 99. |
Which element possess similar property with boron in Newlands' law of octaves ? |
| Answer» SOLUTION :ALUMINIUM | |
| 100. |
Which of the following is in the correct order according to metal reactivity series? |
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Answer» `Al lt FE lt Na lt Ca` `Fe lt Al lt Ca lt Na` |
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