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.
| 202. |
Which of the following statements regarding a catalyst is false ? |
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Answer» It may INCREASE or decrease rate of a REACTION. |
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| 203. |
What is a redex reaction? |
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Answer» Solution :Generally, the oxidation and REDUCTION OCCURS in the same reaction (simultaneously). If one reactant gets oxidised, the other gets reduced. Such reactions are called oxidation-reduction reactions or Redox reactions. EX : `2PbO+Cto 2Pb+CO_(2)` |
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| 204. |
While verifying the law of conservation of mass a student carried out the reaction between silver chloride and silver nitrate in a conical flask. Which of the following will appear as a precipitate? |
| Answer» Solution : Silver chloride | |
| 205. |
Write the balanced equations for the following preparations: (i) Ammonium sulphate from ammonia. (ii) Ammonium phosphate from ammonia. |
| Answer» SOLUTION :N/A | |
| 206. |
What are the applications of Radiochemistry? |
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Answer» Solution :Important applications of radioisotopes are as under - a. Radio carbon DATING - it’s a method by which the AGE of fossil wood or animal is determined using C-14 isotope. b. STUDY of chemical reactions - the nature of some chemical reactions can be studied by mixing a radioisotope with a non-radioactive isotope of the reactants. The radio isotope USED for this purpose is radio tracer. c. Diagnosis - Radioisotope are found very useful to diagnose and understand many DISEASES. |
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| 207. |
Thomson's model of the atom explains the arrangementof fundamental particles in the atom. |
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Answer» |
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| 210. |
Three different atoms of oxygen are represeted as: What do the subdscripts (lower digits) and superscripts (upper digits) represent? (ii) What is name assigned to these as a whole? (iii) Give the nulcear composition of overset(18)underset(8)O |
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| 211. |
What are the three different states of matter? |
| Answer» SOLUTION :Solid, liquid and GAS are the three DIFFERENT STATES of matter. | |
| 212. |
What are the limitations of Mendeleev's periodic table ? |
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Answer» Solution :Limitations of Mendeleev.s periodic table : ELEMENTS with large difference in properties were included in the same group. Eg: Hard metals like COPPER (Cu) and silver (Ag) were included along with soft metals like sodium (Na) and potassium (K). No proper position could be given to the element HYDROGEN. Non-metallic hydrogen was placed along with metals like lithium (Li), sodium (Na) and potassium (K). The INCREASING order of atomic mass was not strictly followed throughout. Eg. Co & Ni, Te & I. No place for isotopes in the periodic table. |
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| 214. |
Which among the following has minimum molarity ? |
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Answer» 20 g of `NaOH` in 100 mL solution 37 g of `Ca(OH)_(2)` in 2000 mL solution has MINIMUM molarity. |
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| 215. |
What is carbon monoxide? Why is it toxic? |
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Answer» Solution :Carbon monoxide is a TOXIC gas of carbon. When fuels UNDERGO incomplete combustion, it results in formation of carbon monoxide. It is released into the atmosphere from various sources like vehicle fuels, domestic fuels, industries, furnaces, etc, cigarette smoking also is a source of carbon monoxide. Carbon monoxide is an odourless toxic gas. When CO enters the human body through breathing, it affects the function of haemoglobin. CO displaces OXYGEN from haemoglobin thereby stopping its function, i.e., SUPPLY of oxygen is blocked to the parts of the body, thereby leading to death. |
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| 216. |
What is newland's law of octaves? |
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| 217. |
What will happen when rainfall occurs in the region without vegetational cover ? |
| Answer» SOLUTION :It will CAUSE LOSS of TOPSOIL. | |
| 218. |
Write the differences between mixture and compounds. |
Answer» SOLUTION :
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| 219. |
Write the chemical formulae of the compounds formed by the following lons: (a) Mg^(2+) and S^(2-) (b) Cu^(2+) and OH^(-) (c) Al^(3+) and Br^(-) |
| Answer» Solution :(a) `Mg^(2+)` and `S^(2-)`: MgS (b) `CU^(2+)` and `OH^(-)` : `Cu(OH)_(2)` (C) `AL^(3+)` and `BR^(-)` : `AlBr_(3)` | |
| 220. |
The smell can bedetected even on repeated dilution of 2mL of dettol in water. |
| Answer» Solution :The PARTICLES of MATTER are minute On dilution of 2mL of DETTOL, the presence of these minute particles is always there in the dilluted solution. Moreover these particles of dettol DIFFUSE in air. HENCE the smell of dettol can be detected. | |
| 221. |
Write down the names of compounds represented by the following formulae . |
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Answer» Solution :(i) Alimininum SULPHATE (ii) CALCIUM Chloride (iii) Potassium Sulphate (iv) Potassium nitrate (v) Calcium CARBONATE |
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| 223. |
What is a matter ? |
| Answer» Solution :ANYTHING which has mass and OCCUPIES space (VOLUME) is called MATTER. | |
| 225. |
Write the steps you would use formaking tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue. |
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Answer» Solution :(1) TAKE a cup of water, as solvent, in a kettle and heat it. (2) ADD sugar, the solute, to water. Heat it. The sugar dissolves in water. (3) Sugar is soluble in water. (4) Add some TEA LEAVES. It is insoluble in water. Colour of tea leaves goes into the solution. (5) Boil the content and add milk, which is soluble in water. (6) Filter the tea with the help of a strainer. The tea collected in the cup is a filtrate. (7) The tea leaves collected on the strainer is residue. |
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| 226. |
What is menat by atomic radius ? |
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| 228. |
Which of the tubes in Figure (a) and (b) will be more effective as a condenser in the distillation apparatus? |
| Answer» Solution :CONSIDER (a) has a number of bends or obstructions. It will PROVIDE more OPPORTUNITY to vapours to condense and act as a BETTER condenser than (B) which has no such obstructions. | |
| 230. |
You are provided with a mixture of naphthalene and ammonium chloride by your teacher. Suggest an activity to separate them with well labelled diagram |
| Answer» Solution :Both naphthalene and ammonium chloride sublime UPON HEATING. Therefore, sublimation technique cannot be used to affect the separation. The separation can be done by dissolving the mixture in completely dry or anhydrous ether taken in a tube. Naphthalene being an organic substance, dissolves in ether whereas ammonium chloride does not dissolve as it is of inorganic nature. The solution formed is immediately filtered (For details, please consult next chapter). Ammonium chloride is left on the filter PAPER as residue. It is dried and coolected. The filtrate is transferred to a china dish and kept in the atmosphere for sometime. Ether readily evaporates as it is a low BOILING liquid. The white residue left in the dish is naphthalene. It can be removed and dried. For more details, please consult next chapter. | |
| 232. |
Wet clothes dry up faster at open place. |
| Answer» Solution :The speed of evaporation depends on the speed of wind. The speed of wind is more at openplace, so the water VAPOUR particles from the CLOTHES are CARRIED AWAY with particles from the clothes are carried away with wind. Hence, wet clothes dry up FASTER at open place. | |
| 233. |
What is the physical state of water at :(a)25^(@)C ?(b) 0^(@)C ?(c )100^(@)C ? |
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Answer» Solution :(a) The physical state of water at `25^(@)C` is liquid. (b)`0^(@)C` is the melting POINT of ice (which is a solid) as well as the FREEZING point of water (which is a liquid). So, the physical state of water at `0^(@)C` can be either a solid (as ice) or liquid). (c )`100^(@)C` is the boiling point of water (which is a liquid) as well as the CONDENSATION temperature of STEAM (which is a gas). So, the physical state of water at `100^(@)C` can be either a liquid or a gas (steam). |
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| 234. |
Whatis a periodic table ? |
| Answer» Solution :DMITRI Mendeleev proposed the law of periodicity which states that "the physical and chemical properties of ELEMENTS are the periodic functions of their atomic MASSES". He arranged 56 elements known at that time according to his law of periodicity. This was best known as the SHORT form of periodic table. | |
| 235. |
What is the modern periodic law? |
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| 236. |
What type of elemetnts does the right portion of the periodic table contain? |
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| 237. |
The symbol of these atoms are given below. _6C^12, _7N^14, _6C^14 What is the basis of your selection? |
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Answer» |
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| 238. |
Which one of the following reduces the penetration of ultraviolet radiation into the earth's surface ? |
| Answer» Answer :D | |
| 239. |
What is the mass of 10 moles of sodium sulphite (Na_(2)SO_(3)) ? |
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Answer» SOLUTION :`Na_(2)SO_(3)` `(Na xx 2) + (1 xx s) + ( 3 xx 0)` `(23 xx 2) + (1 xx 32) + (3 xx 16)` `46 + 32 + 48 = 126, 126 xx 10 = 1260 g ` `116 xx 10 xx 6.023 xx 10^(23)` `1160 xx 6.023 xx 10^(23)` |
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| 240. |
Which among the following is widely used in the match industry ? |
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Answer» `N_2` |
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| 241. |
What does the LPG(Liquefied petroleum gas) contain ? |
| Answer» Solution :LPG is a highly inflammable HYDROCARBON. It contains a MIXTURE of BUTANE and propane GASES. | |
| 242. |
What are called Anaesthetics? How are they classified? |
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Answer» SOLUTION :The DRUGS which cause loss of sensation are CALLED Anaesthetics. Types of Anaesthetics General anaesthetics: They are the agents, which bring about loss of all modalities of sensation, particularly pain along with .reversible. loss of consciousness. Local anaesthetics: They prevent the pain sensation is localised areas WITHOUT affecting the degree of consciousness. |
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| 243. |
Two substances A and B combine togetherto produce a new substance C.The properties of C do not tally with those of A and B. A and B cannotbe separtedinto simplersubstance by any chemical means . Which of the following statements is ( are ) correct about the formation of C? |
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Answer» A and B are ELEMENTS. |
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| 244. |
What happens when water is kept in a plastic bottle wrapped with a wet towel ? |
| Answer» Solution :During the evaporation of water from the wet towel, heat is ABSORBED from the BOTTLE and its CONTENT. DUE to this,the water present in the bottle becomes cool. | |
| 245. |
What is the atomic mass of an element ? |
| Answer» SOLUTION :The ATOMIC mass of an element is the relative mass of its atom as COMPARED to mass of carbon-12 atom. | |
| 246. |
Which of the following concepts , was not considered in Rutherford's atomic model ? |
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Answer» the electrical neutrality of atom |
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| 247. |
When a solid melts its temperature remains the same. So where does the heat energy go? What is the name given to this heat? |
| Answer» Solution :When a SOLID MELTS, the temperature remains the same though the heat is CONTINUOUSLY supplied. The heat supplied is used up in overcoming the force of internomecular ATTRACTION of solid. This RESULTS in the conversion of solid into liquid. This heat is known as latent heat. | |
| 248. |
Write the equation to find out the maximum number of electrons that can be accommodated in a shell. |
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Answer» |
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| 249. |
Which of the following are physical changes? (i) Melting of iron metal (ii) Rusting of iron (iv) Bending of an iron rod (v) Drawing a wire of iron metal |
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Answer» (i), (II) and (III) |
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| 250. |
Which of the following pair is invalid ? |
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Answer» 32g oxygen = `6.022 xx 10^(23)` molecules of oxygen `= 2 xx 6.022 xx 10^(23)` C atoms |
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