This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Preparation of alcohols from carbonyl compounds by Grignard reagent.Explain the given reaction with mechanism. |
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Answer» obtain the three types of MONOHYDRIC alcohols (primary, secondary and TERTIARY alcohols) by using Grignard reagents and carbonyl compounds. The addition of RMgX on carbonyl compounds, along with hydrolysis gives us alcohols. The Grignard reagent is basically an organometallic compound. Let us look at this reaction in greater detail as it is a very important reaction.When we allow a solution of an alkyl halide in dry ethyl ether, (C2H5)O to stand overturnings of metallic magnesium, we WITNESS a vigorous reaction. We can see that the solution turns cloud and begins to boil. The magnesium METAL gradually disappears. The RESULTING solution is the Grignard reagent.The Grignard reagent has the general formula R MgX, and the general name alkyl magnesium halide. |
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| 2. |
Write short note on Preparation of alcohols by fermentation method. |
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Answer» tion:Fermentation is the slow decomposition of COMPLEX organic compounds into SIMPLER organic compounds by the ACTIVITY of enzymes. Enzymes are complex, nitrogenous (proteins), non-living macromolecules of high molecular weight. We usually get these enzymes from living organisms.This process is usually followed by the evolution of gases like CO2 & CH4. They release a lot of energy and are exothermic in nature. The alcoholic fermentation involves the conversion of sugar into ethyl alcohol by YEAST. |
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| 3. |
Write short note on Industrial production of phenol by Dow process and Cumene process. |
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Answer» The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It was invented by Heinrich Hock in 1944 and independently by R. Ūdris and P. Sergeyev in 1942 (USSR).This process converts two relatively cheap STARTING materials, benzene and propylene, into two more valuable ones, phenol and acetone. Other reactants required are oxygen from air and small amounts of a radical initiator. Most of the worldwide production of phenol and acetone is now based on this method. In 2003, NEARLY 7 million TONNES of phenol was produced by the cumene process. In order for this process to be economical, there must also be demand for the acetone by-product as well as theSteps of the processCumene is formed in the gas-phase Friedel–Crafts alkylation of benzene by propylene. Benzene and propylene are compressed together to a pressure of 30 standard atmospheres at 250 °C (482 °F) in presence of a catalytic Lewis acid. Phosphoric acid is often favored over aluminium halides. Cumene is oxidized in air, which removes the tertiary benzylic hydrogen from cumene and hence forms a cumene radical:The cumene radical then BONDS with an oxygen molecule to give cumene peroxide radical, which in turn forms cumene hydroperoxide (C6H5C(CH3)2-O-O-H) by abstracting a benzylic hydrogen from another cumene molecule. This latter cumene converts into cumene radical and feeds back into subsequent chain FORMATIONS of cumene hydroperoxides. A pressure of 5 atm is used to ensure that the unstable peroxide is kept in liquid state. |
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| 5. |
How to find charge of an element |
| Answer» NG at the periodic table you will know the CHARGE of an ELEMENT. Hope it helps, plzz follow me. THANKS plzz ❤❤❤❤❤ | |
| 6. |
Which of the following is an example of a positive ion and negative ion that is isoelectronic with Argon and why1) K+ and Cl- or Ca2+ and S2-2) Na+ and For Mg2+ and O2-3) K +and I- or Mg2+ and S2-4) K +and I- or Ca2+ and 02- |
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Answer» 1 is the answerExplanation:isoelectronic species have same no. of electronshere,K+(Atm. No. 19)loses one e-&Cl-(Atm. No.17) GAIN one e-For completing their octet and to acquirenoble gas configuration which is similar to Argon ( Atomic no. 18)similarly Ca2+(Atm. No. 20) loses two e-and S2- (Atm. No.16) gain to e- |
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| 8. |
2. Which among the following group elements are smaller in size and why1) I A group2) II A group3) VII A group4) VI A group |
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Answer» VII A group is SMALLER in sizeExplanation:This is because as we move left to RIGHT ACROSS a PERIOD the atomic size decreases and as we move TOP to bottom atomic size increases. |
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| 9. |
What is the mass of buthanol? |
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Answer» 74.1 g/mol...FORMULA: C4H10OFormula: C4H10OMelting POINT: -90 °C.... |
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| 10. |
Give me some examples of carbonates and bicorbonates reacting with acids |
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Answer» CaCO3,NaHCO3Explanation:Both react with acid to LIBERATE CO2 GAS |
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| 11. |
Which statement from the following is true?Select the proper choice from the given multiple choices. (A) During dehydration reaction H₂0 molecule is added to reactant (B) Lucas test is used for detection of ethers (C) During esterification OH⁻ from acid molecule and H⁺ from alcohol are removed (D) During esterification H⁺ from acid molecule and OH⁻ from alcohol are removed |
| Answer» C) During ESTERIFICATION OH- from ACID MOLECULES ....... | |
| 12. |
Explain classification of haloalkane and haloarene compounds on the basis of number of halogen atoms.Give answer of the question in detail. |
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| 13. |
Mention types of freon and explain freon as coolant.Give answer of the question in detail. |
| Answer» FREON is a GAS. It is USED in refrigerators for frozen FOOD | |
| 14. |
Write a note on resonance effect in the nucleophilic substitution reaction of haloarenes. |
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Answer» A REACTION in Explanation:Which one nucleophile is SUBSTITUTE by other nucleophile is CALLED NUCLEOPHILIC SUBSTITUTION |
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| 15. |
Explain the factors affecting the rate of reaction in SN¹ and SN² reactions. |
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Answer» tion:Factors affecting SN11) Nature of alkyl halide stability of carbocation increases.... the rate of SN1 increases 2)Nature of Leaving groupweaker the BASE ==> better leaving GROUP3) Nature of SolventPolar Protic solvent ⬆️ dielectric constant ⬆️ rate of SN1Factors affecting SN21 1 the rate is INVERSELY proportional to steric crowding 2 to stability of transition state most stable the transition state more will be the SN2 reaction the electron withdrawing GROUP stabilizes the transition state and hence SN2 will be more and more stable 3 stronger the nucleophile higher will be the rate of reaction weak nucleophile shoes SN1 action please mark as brainliest . |
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| 16. |
Write preparation of methylene chloride. |
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Answer» Methylene chloride can be prepared by any of the following methods:1. The reaction of CHLOROFORM with ZINC and HYDROCHLORIC ACID in an alcoholic solution.2. By chlorination of methane or methyl chloride( better alternative).In order to obtain a good amount of methylene chloride, it is better to take an excess of methyl chloride. |
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| 17. |
Mention the classification of haloalkanes on the basis of number of halogen atoms giving suitable examples. |
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Answer» tion:HALOALKANE are CLASSIFIED into two Main TYPES monohalogen DERIVATIVES and polyhalogen derivatives polyhalogen derivatives are further classified into thto four types DIHALOGEN,trihalogen,tetrahalogen and polyhalogen |
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| 18. |
In haloalkanes intermolecular attraction forces are more than those in alkanes? Why |
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Answer» Hey mate ,Haloalkanes generally have a boiling point that is higher than the ALKANE they are derived from. This is due to the INCREASED molecular weight due to the large HALOGEN ato and the increased intermolecular forces due to the POLAR binds and increase POLARIZIBILITY of halogenHope this will help uh |
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| 19. |
Explain the reaction for preparation of haloalkane from alcohol giving reaction equation. |
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Answer» Alcohol REACT withHcl in the PRESENCE of ZnCl2 to form HALO alkans. Explanation:Alcohol react with PCL5 (or.) PCL3 ( or) socl2 to form halo alkans |
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| 20. |
Give reason for polarity of C-X bond in haloalkane. |
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Answer» The C-X BOND is highly polar in nature because halogen atoms are electronegative and the carbon atom is ELECTROPOSITIVE. The difference in electronegativity results in withdrawal of electron DENSITY from sigma bond pair towards the halogen atom. ... Electronegativity of X: F(3.98) > CL(3.16) > BR(2.96) > I(2.66).m.. |
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| 21. |
Give examples of 1°, 2°,3° haloalkanes. |
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Answer» CH3-cl and CH3-I is1°. Propanaldihide is 3°. BETA HYDROXY butanaldihide(ALDOL) is 2° |
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| 23. |
2-bromo-3 methyl pentane.Write the structural formulas of it. |
| Answer» CHEMICAL NAMES: 2-bromo-3-methylpentane62168-41-6SCHEMBL1522410AKOS0...Chemical Names: 2-bromo-3-methylpentane62168-41-6SCHEMBL1522410AKOS0...MOLECULAR Formula: C6H13BrChemical Names: 2-bromo-3-methylpentane62168-41-6SCHEMBL1522410AKOS0...Molecular Formula: C6H13BrMolecular Weight: 165.074 g/molChemical Names: 2-bromo-3-methylpentane62168-41-6SCHEMBL1522410AKOS0...Molecular Formula: C6H13BrMolecular Weight: 165.074 g/molPubChem CID: 19612097.... | |
| 24. |
Discuss the industrial production of sulphuric acid by contact process.Write answer in detail. |
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Answer» lso a CENTRAL substance in the chemical industry. It is widely produced by contact process. Now a days, sulphuric acid is prepared by contact process all over the world. Preparation of sulphuric acid by contact process is based upon the catalytic oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3).GET startedManufacturing of sulfuric acid by Contact processWorldOfChemicalsWorldOfChemicalsOct 13, 2014 · 2 min readSulfuric acid (H2SO4) is a highly corrosive strong mineral acid. Sulfuric acid has a wide range of applications including domestic acidic drain cleaner, electrolyte in lead-acid batteries and various cleaning agents. It is also a central substance in the chemical industry. It is widely produced by contact process.Production of sulfuric acid by contact process —Now a days, sulphuric acid is prepared by contact process all over the world. Preparation of sulphuric acid by contact process is based upon the catalytic oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3).The Contact Process involves the following steps:To make sulfur dioxideconverting sulfur dioxide into sulfur trioxide (the reversible reaction at the heart of the process)Converting sulfur trioxide into concentrated sulfuric acid.To make sulfur dioxideSulfur dioxide can be obtained by burning sulfur in an excess of air -S (s) + O2 (g) → SO2 (g)Sulfur dioxide can also be obtained by heating sulfide ores LIKE pyrite in an excess of air:4FeS2(s) + 11O2(g) → 2Fe2O3(s )+ 8SO2(g)In either case, an excess of air is used so that the sulfur dioxide produced is already mixed with oxygen for the next stage.Converting sulfur dioxide into sulfur trioxideThis is a reversible reaction, and the formation of the sulfur trioxide is exothermic.2SO2(g) + O2(g) → 2SO3 (g) ΔH = -196 KJ mol-1 Converting sulfur trioxide into sulfuric acidConverting sulfur trioxide to sulfuric acid cannot be done just by adding water, as the reaction is so uncontrollable that it creates a fog of sulfuric acid. Instead, the sulfur trioxide is FIRST dissolved in concentrated sulfuric acid:H2SO4 (l) + SO3(g) → H2S2O7 (l)(oleum)The product is known as fuming sulfuric acid or oleum. This can then be reacted safely with water to produce concentrated sulfuric acid — twice as much as you originally used to make the fuming sulfuric acid.H2S2O7 (l) + H2O → 2H2SO4 (l) |
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| 25. |
Explain the anomalous behaviour of nitrogen element from other elements of group 15.Write answer in detail. |
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Answer» the anomalous features of the element Nitrogen are listed below :1. It's size is small. Also, it has high electronegativity. It lacks the d-orbitals.2. It possesses the capacity of formation of p-pi p-pi bonds with ownself and also with elements like oxygen and carbon.3. Nitrogen can FORM a diatomic molecule with three bonds between TWO N atoms. It also has high BOND ENTHALPY. |
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| 26. |
Mention oxidation states of elements of group 16. |
| Answer» GROUP 16 is the oxygen family. they USUALLY have -2 OXIDATION stateExplanation: | |
| 27. |
What is meant by interhalogen compounds? Mention its types and give one example of each. |
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Answer» an INTERHALOGEN compound which contain DIFFERENT halogen atoms (FLUORINE,chlorine,BROMINE,IODINE or astatine) |
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| 28. |
Write two reactions of preparation of dioxygen gas. |
| Answer» H2O2 ---> H2O + O2KCLO3 +∆ --->KCL + O2ARE THE TWO BASIC REACTIONS WHICH ARE HELPFUL IN PREPARING OXYGEN GASI MUST TELL YOU THAT DIOXYGEN GAS IS NOTHING BUT OXYGEN GAS WHICH HAS SYMBOL O2 | |
| 29. |
M sorry the image didnt load the previous time so here it is again.........plizz help me with #2 |
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| 30. |
If IE 1 of He atom is 24.5ev.tgen it's IE2 will be Let's Seee ur chem |
| Answer» TION:SEE the ATTACHMENT....... | |
| 31. |
If IE 1 of He atom is 24.5ev.tgen it's IE2 will be |
| Answer» TION:SEE the ATTACHMENT...... | |
| 32. |
Which set of elements shows positive electron gain enthalpy? (1) He, N, O(2) Ne, N, CI(3) O, CI, F(4) N, He, Ne |
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| 33. |
Is ferric oxide produced by the decomposition of ferrous sulphate pure. Explain and justify. |
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Answer» yes...when FERROUS sulphate is heated is give FERRIC OXIDE,sulphur TRIOXIDE and sulphur dioxideequation-feSO4------->fe2O3+SO2+SO3 |
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| 34. |
What is a periodic change |
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Answer» changes which happen over a DEFINED AMOUNT of TIME :Ex. seasonsExplanation: |
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| 36. |
Which of the following orders with reference to stability is correct?Select the proper choice from the given multiple choices. (A) HF > HBr > HC1 > HI (B) HI < HC1 < HBr < HF (C) HF > HC1 > HBr > HI (D) HF > HI > HC1 > HBr |
| Answer» STABILITY order=HF>HCL>HBR>HI | |
| 37. |
Which allotrope of phosphorus is stored in water?Write answer of the given question in short. |
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Answer» Explanation:This makes it a very DANGEROUS element if not handled properly. However, PHOSPHORUS is also insoluble in water. When KEPT under water, it is easy to carry and prevents it from DIRECTLY reacting with Oxygen in the air. White phosphorus is extremely receptive CONTRASTED with every other allotrope of phosphorus |
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| 38. |
Froth floatation method becomes inevitable for the ore containing sulphide.Give reasons for the given phenomena. |
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Answer» type of method in which a froth is made by MIXING oil of PINE and water. This method is employed to separate the ores of sulphide.It becomes inevitable because the ore of sulphide gets WET by the oil of pine and hence brings this with the froth. So, this method is used to separate the ores of sulphide. |
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| 39. |
Describe in detail the method to obtain pure alumina from bauxite.Write answer in details of the given question. |
| Answer» MINERALS are naturally occurring INORGANIC solids with a crystalline structure and a definite range of chemical formula. Ores are concentrations of minerals in rock that are HIGH enough to be economically extracted for use. All ores are minerals, but all minerals are not necessarily ores.Rocks- A rock is made up of 2 or more minerals. You need minerals to make rocks, but you don't need rocks to make minerals. All rocks are made of minerals.Minerals- A mineral is composed of the same substance throughout. There are about 3000 different minerals in the world. Minerals are made of chemicals - EITHER a single chemical or a combination of chemicals.There are 103 known chemical elements. Minerals are sorted into 8 groups.Difference between rock and mineral - A rock is made up of 2 or more minerals, whereas a mineral is composed of the same substancethroughout.Ore- A mineral occurring in sufficient quantity and containing enough metal to permit its recovery and extraction at a profit. Or, a mineral or an aggregate of minerals from which a valuable constituent, especially a metal, can be profitably mined or extracted is an ore | |
| 40. |
Write chemical reactions occurring in the different ranges of temperature in blast furnace.Answer the given question in brief. |
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Answer» blast furnace, there are several chemical reactions taking place; that eventually result in the desired product (iron) being extracted. The coke (carbon) burns with oxygen to produce carbon dioxide. This reaction is exothermic. The CO2 then reacts with more coke to give carbon monoxide. C + O2 ==>> CO2 CO2 + C ==>> 2CO Carbon monoxide acts as a REDUCING agent and reacts with the iron ore to give molten iron, which trickles to the BOTTOM of the furnace where it is collected. FE2O3 + 3CO ==>> 2Fe + 3CO2 The LIMESTONE in the furnace decomposes, forming CALCIUM oxide. This is a fluxing agent and combines with impurities to make slag, which floats on top of the molten iron and can be removed. CaO + SiO2 ==>> CaSiO3 |
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| 41. |
Explain the principle of zone refining method and show which metal can be refined by it.Answer the given question in brief. |
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Answer» nciple of the METHOD of zone refining is that - the impurities in molten TYPE of state of metal has more solubility than in a solid state.MECHANISM :In one of the ends of a rod, a movable circular heater is attached. The molten part of the rod also begins moving ALONG with the moving of the heater. By doing this, the metal which is pure comes out of the MELT and the impurities goes to the molten part.Gallium, Indium, BORON, Silicon can be refined by this process. |
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| 42. |
Describe in brief the methods for obtaining ore from mineral. Write answer in details of the given question. |
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Answer» Minerals are naturally occurring inorganic SOLIDS with a crystalline structure and a definite range of CHEMICAL formula. Ores are concentrations of minerals in rock that are high enough to be economically extracted for use. All ores are minerals, but all minerals are not necessarily ores.Rocks- A rock is made up of 2 or more minerals. You need minerals to make rocks, but you don't need rocks to make minerals. All rocks are made of minerals.Minerals- A mineral is composed of the same substance throughout. There are about 3000 DIFFERENT minerals in the world. Minerals are made of chemicals - either a single chemical or a combination of chemicals.There are 103 known chemical elements. Minerals are sorted into 8 groups.Difference between rock and mineral - A rock is made up of 2 or more minerals, whereas a mineral is composed of the same substancethroughout.Ore- A mineral occurring in sufficient QUANTITY and containing enough metal to permit its recovery and extraction at a profit. Or, a mineral or an aggregate of minerals from which a VALUABLE constituent, especially a metal, can be profitably mined or extracted is an ore |
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| 43. |
Write the Kohlrausch’s law of independent migration of ions and explain.Write answers of the given question in details. |
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Answer» inciple is known as KOHLRAUSCH's law of independent migration , which STATES that in the LIMIT of infinite dilution, Each ionic species makes a contribution to the conductivity of the solution that DEPENDS only on the nature of that particular ION, and is independent of the other ions present. |
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| 44. |
What is storage cell? Explain lead storage cell.Write answers of the given question in details. |
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Answer» or connected group of cells that converts chemical energy into electrical energy by reversible chemical reactions and that may be recharged by passing a current through it in the direction OPPOSITE to that of its discharge. — CALLED also STORAGE CELL. |
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| 45. |
Write the classification of cells which are industrially useful and give example |
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Answer» Industrial MicrobiologyIndustrial MicroorganismsThere are various types of MICROORGANISMS that are used for large-scale production of industrial items.LEARNING OBJECTIVESDescribe how microorganisms are used in industry to manufacture food or products in large quantitiesKEY TAKEAWAYSKey PointsThe ability of specific microorganisms to produce specialized enzymes and proteins has been exploited for many purposes in industry.Industrial microorganisms are used to produce many things, including food, cosmetics, pharmaceuticals and construction materials.Microorganisms can be genetically modified or engineered to aid in large-scale production.Key Termsexopolysaccharide: a type of sugar-composed polymer secreted by a microorganism into the external environmentarchaea: a taxonomic domain of single-celled organisms lacking nuclei that are fundamentally from bacteria.Industrial microbiology includes the use of microorganisms to manufacture food or industrial products in large quantities. Numerous microorganisms are used within industrial microbiology; these include naturally occurring organisms, laboratory selected mutants, or even genetically modified organisms (GMOs). Currently, the debate in the use of genetically modified organisms (GMOs) in food sources is gaining both momentum, with more and more supporters on both sides. However, the use of microorganisms at an industrial level is deeply rooted into today’s society. The following is a brief overview of the various microorganisms that have industrial uses, and of the roles they play.Archaea are specific types of prokaryotic microbes that exhibit the ability to sustain populations in unusual and typically harsh environments. Those suriving in the most hostile and extreme settings are known as extremophile archaea. The isolation and identification of various types of Archaea, particularly the extremophile archaea, have allowed for analysis of their metabolic processes, which have then been manipulated and utilized for industrial purposes.Extremophile archaea species are of particular interest due to the enzymes and molecules they produce that allow them to sustain life in extreme climates, including very high or low temperatures, extremely acid or base solutions, or when exposed to other harmful factors, including radiation. Specific enzymes which have been isolated and used for industrial purposes include thermostable DNA polymerases from the Pyrococcus furiosus. This type of polymerase isa common TOOL in MOLECULAR biology; it is capable of withstanding the high temperatures that are necessary to complete polymerase chain reactions. Additional enzymes isolated from Pyrococcus speciesinclude specific types of amylases and galactosidases which allow food processing to occur at high temperatrues as well.Corynebacteria are characterized by their diverse origins. They are found in numerous ecological niches and are most often used in industry for the mass production of amino acids and nutritional factors. In particular, the amino acids produced by Corynebacterium glutamicum include the amino acid glutamic acid. Glutamic acid is used as a common additive in food production, where it is known as monosodium GLUTAMATE (MSG). Corynebacterium can also be used in steroid conversion and in the degradation of hydrocarbons. Steroid conversion is an important process in the development of pharmaceuticals. Degradation of hydrocarbons is key in the breakdown and elimination of environmental toxins. Items such as plastics and oils are hydrocarbons; the use of microorganisms which exhibit the ability to breakdown these compounds is critical for environmental protection.imageCorynebacterium: Corynebacterium species are often used to mass produce amino acids utilized in food processing.Xanthomonas, a type of Proteobacteria, is known for its ability to cause disease in plants. The bacterial species which are classified under Xanthomonas exhibit the ability to produce the ACIDIC exopolysaccharide commonly marketed as xanthan gum, used as a thickening and stabilizing agent in foods and in cosmetic ingredients to prevent separation. |
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| 46. |
Explain Gibbs’ free energy and cell potential. |
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Answer» free Energy is a thermodynamic quantity equal to the enthalpy (of a SYSTEM or process) minus the product of the ENTROPY and the absolute temperature.The POTENTIAL difference between the two ELECTRODES of a galvanic cell is CALLED cell potential. It is represented by volt. |
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| 47. |
Write usefulness of cell potential. |
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Answer» The cell potential (VOLTAGE) for an electrochemical cell can be predicted from half-reactions and its operating conditions (CHEMICAL nature of materials, temperature, gas partial pressures, and concentrations). Cell voltage is right one to be used to represent summative effect of both the ELECTRODE potentials.hope this answer will help please like and MARK as a brainliest and follow me.♥️♥️♥️♥️♥️ |
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| 48. |
Is the weight of water in a basin the same as when live fish is put in it? |
| Answer» YES, WEIGHT of WATER WOULD be constant.Explanation: | |
| 49. |
7. Which of the following pair will show maximum difference of their radii : (a) Mn, Fe(6) K, Ca(c) Cr, Mn(d) Co, Ni |
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