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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. |
6. The limiting value of wave number in Lyman seriesof hydrogen atoms is1) 109678 cm- 2) 109678/2 cm3) 109678/5 cm 4) 2x109678/3 cm |
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Answer» Answer: 1) 109678 cm-1 is the LIMITING VALUE of WAVENUMBER in LYMAN SERIES. |
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| 2. |
___ heya pp -----# question of the day !!what happens when magnesium reacts with boiling water???..... |
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Answer» Answer: MAGNESIUM does not REACT with water to any significant extent. ... Magnesium METAL does however react with steam to give magnesium oxide (MgO) (or magnesium hydroxide, Mg(OH)2, with excess steam) and HYDROGEN gas (H2). |
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| 3. |
Balance the eqation mg + dil.suphuric acid =mgso4+water |
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Answer» Answer: 2mg+2H2so4______2mgso4+ 2H2O |
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| 4. |
ChemistryAmonia was prepared by 50g of N2. and8g of H2 then find out the limiting reagentand excess reagent and amount of Amónia |
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Answer» LIMITING reagent is Hydrogen excess reagent is nitrogen |
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| 6. |
Write brief sketch of pharmaceutical analysis |
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Answer» Answer: HERE YOUR ANS MATE Explanation: 1. Pharmaceutical Analysis 2. Pharmaceutical analysis Pharmaceutical Analysis may be defined as the application of analytical procedures used to determine the purity, safety and quality of drugs and chemicals This course has access to the full range of TITRATION method SPECTROSCOPIC technique Chromatographic method Spectrophotometry etc. 3. Titration method Aqueous acid base titration: An aqueous acid–base titration is the determination of the concentration of an acid or base by exactly neutralizing the acid or base with an acid or base of known concentration. This allows for quantitative analysis of the concentration of an unknown acid or base solution. Aqueous acid–base titrations can also be used to find PERCENT purity of chemicals. Non aqueous acid base titration: Non aqueous titration is the titration of substances dissolved in solvents other than water. it provides a solvent in which organic compounds are soluble. The most commonly used procedure in this titration of organic bases with perchloric acid in anhydrous acetic acid. It is the most common titrimetric procedure used in pharmacopoeial assays and is suitable for the titration of very weak acids and very weak bases 4. Titration method Redox titration: A redox titration is a type of titration based on a redox reaction between the analyte and titrant. concentration of certain chemicals in pharmaceutical compounds can be determined through redox titration. Complexometric titration:Complexometric titration is a form of volumetric analysis in which the formation of a colored complex is used to indicate the end point of a titration. particularly useful for the determination of a mixture of different metal ions in solution 5. Potentiometric titration • Potentiometric titration is a technique similar to direct tritration of a redox reaction. It is a useful means of characterizing an acid. No indicator is used; instead the potential is measured across the analyte, typically an electrolyte solution. 6. Amperometric titration: Refers to a class of titrations in which the equivalence point is determined through measurement of the electric current produced by the titration reaction. It is a form of quantitative analysis. Aquametry : Aquametry in analytical chemistry refer to analytical processes to measure the water present in materials. Use : The methods widely used in aquametry encompasses Karl Fischer titration, distillation, chromatography etc. 7. Refractometry is the method of measuring substances' refractive index (ONE of their fundamental physical properties) in order to, for example, assess their composition or purity. Polarimetry is a sensitive, nondestructive technique for measuring the optical activity exhibited by inorganic and organic compounds. Nephelometry is a technique used in immunology to determine the levels of several blood plasma proteins. 8. Spectroscopy Method Introduction to Visible & Ultraviolet Spectroscopy: Spectroscopy is the science which deals with the interaction between a matter (atom/molecule) and an electromagnetic radiation. Ultraviolet and visible spectroscopy is a type of absorption spectroscopy that uses the ultraviolet and visible parts of the electromagnetic spectrum. 9. Chromatography Chromatographic Methods: Chromatography is usually a technique for separating and / or identifying the components in a mixture. It is powerful method in industry. Some major types of chromatography: Paper chromatography Gas chromatography Liquid chromatography High performance liquid chromatography Gel filtration chromatography 10. HPLC High Performance Liquid Chromatography: High performance liquid chromatography (HPLC) is a very EFFICIENT separation technique, that is, it yields excellent separation in a very short period of time. HPLC is a form of column chromatography. Its frequently used in biochemistry and analytical chemistry to separate component mixture. 11. Flurometry: An analytic method for detecting fluorescent compound using a beam of ultraviolet light that excites the compounds and causes them to emit visible light. pls mark me as brainest |
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| 7. |
What are the examples of heterogeneous catalysis and homogeneous catalysis? at least 3 examples. |
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Answer» Answer: hello Explanation: A catalyst is a compound used to help a reaction occur faster by lowering the ACTIVATION energy. There are two types of catalysts, homogeneous and HETEROGENEOUS. A homogeneous catalyst is a catalyst that is in the same PHASE as the REACTANTS, while a heterogeneous catalyst is in a DIFFERENT phase than the reactants.
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| 8. |
the displacement of valency of electrons resulting in polarization of an organic molecule is called _______. |
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| 9. |
Balanced eqation of mg + dil.suphuric acid = mgso4+ h2o |
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Answer» Explanation: BALANCED EQUATION IS :- Mg + H2SO4 -------- MgSO4 + H2 This is a DISPLACEMENT REACTION |
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| 10. |
Explain the homologous serious of alchol |
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Answer» Answer: A homologous series is a series of COMPOUNDS with the same functional group and SIMILAR chemical properties in which the members of the series differ by the number of REPEATING units they CONTAIN. The functional group which represents alcohol is and has SUFFIX ol. |
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| 11. |
What is the stationary phase in paper chromatography? |
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Answer» Answer: In PAPER chromatography stationary PHASE is strip of filter paper and the MOBILE phase is SPOT of black ink. Hope it helps you! |
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| 12. |
What react with sulphuric acid to give no white precipitate |
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| 13. |
Name the ion made by non metal -cation/ anion |
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Answer» Answer: non metals GAIN electrons and make NEGATIVELY charged IONS CALLED anions |
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| 14. |
Mole fraction of A in water is 0.2 . The molality of A in water is? |
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| 15. |
What steps can be taken to restore the ganga to past glory |
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| 16. |
What is the name of the phenomenon that is taking place? |
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Answer» Answer: there are MANY phenomenon taking PLACE around US physical chemical biological |
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| 17. |
1.Name three luminous objects.2. If you stand in fron. stand in front of a mirror in a completely dark room, will you see your image in theot does a pinhole camera form-an image or a shadow?3. What dou see your image in the mirror?á What is the colour of a shadow? 4 what is the colour of a shadow |
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Answer» Answer: 1 opaque TRANSPARENT translucent 3 virtual 4 BLACK |
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| 18. |
Why do the divers compressed gas cylinders? |
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| 19. |
Why do the liquid have the definite volume but not definite shape? |
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Answer» In liquids, the particles of MATTER are having some space between them, so liquids have a definite VOLUME. However, because the particles can move freely, a liquid has no definite SHAPE and takes the shape of its container. |
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| 20. |
Chemistry icse selina class 9 |
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Answer» Answer: PLEASE mark me brainly and follow and thank meExplanation: Sleep mode stores the documents and files you are operating into the RAM, using a small amount of power in the PROCESS. Hibernate mode ESSENTIALLY does the same thing, but saves the information to your HARD disk, which allows your computer to be TURNED off completely and use no energy. |
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| 21. |
Explain the varna system. what change did it undergo during later Vedic period |
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Answer» Answer: The Varna system was DIVIDED into 4 parts Bhramins Kshatriyas Vaishyas Sudras Explanation: In later vedic period Varnas BECOME heridity and very RIGID. It was compalsary. No ONE can change their occupation |
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| 22. |
10 ml of N/2HCI, 30 ml of N/10 HNO, 75 ml of N/5H2so4, are mixed together. The normality ofresulting solution is(1) 0.02 N(2) 0.5 N(3) 0.2 N(4) 0.025 N |
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Answer» CORRECT answer is 0 2N.Here is your answer. |
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| 23. |
Give the meaning of the term water table |
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| 24. |
Tanu Sulphuric Amla copper plate per dala tha To Kya Hota Hai Hindi mein answerChemistry's main |
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Answer» Answer: (स गं, अर्थात् गंधक) आधुनिक विचारधारा के अनुसार सलफ़्यूरिक अम्ल के अणु की संरचना चतुष्फलक (TETRAHEDRON) होती है, जिसमें गंधक का एक परमाणु केंद्र में और दो हाड्रॉक्सी समूह तथा दो ऑक्सीजन के परमाणु चतुष्फलक के कोणोंश् पर स्थित हैं। अम्ल के अणु की संरचना में गंधक-ऑक्सीजन बंध का अंतर 1.51 ऐं. (ऐंग्सट्रॉम इकाई) होता है। शत प्रतिशत शुद्ध सलफ़्यूरिक अम्ल का घनत्व 15 सें. पर 1.8384 ग्राम प्रति मिलिलिटर होता है। सलफ़्यूरिक अम्ल को गरम करने से उससे सल्फ़र ट्राइऑक्साइड का वाष्प निकलने लगता है तथा अम्ल का 290 सें. से क्वथन प्रारंभ हो जाता है। क्वथनांक में तब तक वृद्धि होती जाती है, जब तक ताप 317 सें. नहीं पहुंच जाता। इस ताप पर सलफ़्यूरिक अम्ल 98.54 प्रतिशत रह जाता है। उच्च ताप पर सलफ़्यूरिक अम्ल का विघटन शुरु हो जाता है और जैसे जैसे ताप ऊपर उठता है विघटन बढ़ता जाता है। सांद्र सलफ़्यूरिक अम्ल जल के साथ सलफ़्यूरिक अम्ल मोनोहाइड्रेट, गलनांक 8.47 सें., सलफ़्यूरिक अम्ल डाइहाइड्रेट, गलनांक 39.46 सें. तथा सलफ़्यूरिक अम्ल टेट्राहाइड्रेट, गलनांक 28.25 सें., बनाता है। जल के साथ क्रिया के फलस्वरूप प्रति ग्राम सांद्र अम्ल 205 कैलोरी उष्म का उत्पादन करता है। सांद्र अम्ल कार्बनिक पदार्थों, लकड़ी तथा प्राणियों के ऊतकों से जल खींच लेता है, जिसके फलस्वरूप कार्बनिक पदार्थों का विघटन हो जाता है और अवशेष के रूप में कोयल रह जाता है। सलफ़्यूरिक अम्ल लवण बनाता है, जिसे सल्फ़ेट कहते हैं। सल्फ़ेट सामान्य या उदासीन लवण होते हैं, जैसे सामान्य सोडियम सल्फ़ेट (NA2SO4) या अम्लीय सोडियम बाइसल्फ़ेट (NaHSO4)। अम्लीय इसलिए कि इसमें अब भी एक हाइड्रोजन रहता है, जो क्षारकों से प्रतिस्थापित हो सकता है। धातुओं, धातुओं के ऑक्साइडों, हाइडॉक्साइडों, कार्बोनेटो या अन्य लवणों पर अम्ल की क्रिया से सल्फ़ेट बते हैं। अधिकांश सल्फेट जलविलेय होते हैं। केवल कैल्सियम, बेरियम, स्ट्रौंशियम और सीस के लवण जल में अविलेय या बहुत कम विलेय होते हैं। अनेक लवण औद्योगिक महत्व के हैं। बेरियम और सीस सल्फ़ेट वर्णक के रूप में, सोडियम सल्फ़ेट कागज निर्माण में, कॉपर सल्फ़ेट कीटनाशक के रूप में और कैल्सियम सल्फ़ेट प्लास्टर ऑव पैसि के रूप में प्रयुक्त होते हैं। सीस और इस्पात पर सांद्र अम्ल की कोई क्रिया नहीं होती। अत: अम्ल के निर्माण में तथा अम्ल को रखने के लिए सीस तथा इस्पात के पात्र प्रयुक्त होते हैं। बड़े पैमाने पर सल्फ़्यूरिक अम्ल के निर्माण का पहला कारखाना 1740 ई. में लंदन के समीप रिचमंड में वार्ड नामक वैज्ञानिक द्वारा स्थापित किया गया था। निर्माण के लिए गंधक तथा शोरे के मिश्रण को लोहे के पात्र में गरम किया जाता था और अम्ल के वाष्प को काँच के पात्रों में जिनमें जल भरा रहता था, एकत्र किया जाता था। इस प्रकार से प्राप्त तनु अम्ल को बालु ऊष्मक के ऊपर काँच के पात्रों में सांद्र किया जाता था। कुछ समय पश्चात् शीघ्र टूटनेवाले काँच के पात्रों के स्थान पर छह फुट चौड़े सीस कक्षों का प्रयोग होने लगा। होल्केर नामक वैज्ञानिक के अयक परिश्रम द्वारा 1810 ई. में आधुनिक सीसकक्ष विधि का प्रयोग प्रारंभ हुआ। 1818 ई. से सल्फर डाइऑक्साइड की प्राप्ति के लिए कच्चे माल गंधक के स्थान पर पाइराइटीज़ नामक खनिज का प्रयोग होने लगा। 1827 ई. में गे-लुपैक स्तंभ तथा 1859 ई. में ग्लोब्रर स्तंभ के विकास द्वारा सीस-कक्ष-विधि का आधुनिकीकरण हुआ। यहाँ नाइट्रोजन के ऑक्साइड, सल्फ़र डाइऑक्साइड तथा वायु को कक्ष में प्रवेश कराया जाता है। ऐसे गैस मिश्रण को 25 फुट ऊँचे ग्लोवर स्तंभ में नीचे से प्रवेश कराया जाता है। इस स्तंभ में ऊपर से गे-लुसैक स्तंभ का सल्फ़्यूरिक अम्ल तथा नाइट्रोसिल सल्फ़्यूरिक अम्ल का मिश्रण टपकता है। स्तंभ से निकलकर गैस मिश्रण सीस कक्ष में प्रवेश करता है। साधारणतया सीस कक्ष तीन रहते हैं। यहाँ कक्ष में भाप भी प्रवेश करता है। गैस मिश्रण और भाप के बीच क्रिया होकर, सल्फ़्यूरिक अम्ल बनकर, कक्ष के पेंदे में इकट्ठा होता है। अवशिष्ट गैसे अब गे-लुसैक स्तंभ में प्रवेश करती हैं। इनमें प्रधानतया नाइट्रोजन के ऑक्साइड रहते हैं। गे-लुसैक स्तंभ कोक या पत्थर के टुकड़ों से भरा रहता है। उसमें ऊपर से सल्फ़्यूरिक अम्ल टपकता है और रुकावट के कारण धीरे धीरे गिरकर, नाइट्रोजन के ऑक्साइडों को अवशोषित कर, नाइट्रोसिल सल्फ़्यूरिक अम्ल बनता है और ग्लोवर स्तंभ में प्रयुक्त होता है। इस प्रकार नाइट्रोजन के ऑक्साइडों की क्षति बचाई जाती है। सीस कक्ष से प्राप्त अम्ल अशुद्ध होता है। अशुद्धियों में आर्सोनिक, नाइट्रोजन के ऑक्साइड तथा कुछ लवण होते हैं। ऐसा अम्ल प्रधानतया उर्वरक के निर्माण में प्रयुक्त होता है। इसके लिए शुद्ध अम्ल आवश्यक नहीं है। ऐसा अम्ल सस्ता होता है |
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| 25. |
Why neon and argon are unreactive gases |
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Answer» hii frnd Explanation:
The neon and argon belongs to noble gases as they have full filled configuration they are STABLE there is no need to REACT with other atoms to attain stability...... but there are some exceptions with xenon even it is noble gas it forms compound it is it's UNIQUE property.. hope it helps U friend....... |
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| 26. |
Iron reacts with dilute hydrocloric acid one word equation |
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Answer» Explanation: There is no 1 word, instead 2Fe+ 6HCl > 2FeCl3 + 3H2... Pls MARK as brainliest....!!! |
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| 27. |
Blue litmus; turmeric phenolphthalein; digenewhich is not an indicator |
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Answer» Answer: HEY MATE YOUR ANS Explanation: ALL ARE INDICATORS AS THEY GIVE ODOUR WHEN REACT WITH ACID OR BASE HOPE YOU LIKE MY ANSWER |
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| 28. |
On explosion of sodium cabonate salt to the atmosphere changes into powder state why plz answer |
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Answer» The sodium metal reacts with water. So much heat is RELEASED that the sodium melts. It turns into a tiny ball of liquid sodium. ... The hydrogen GAS CATCHES fire and causes the ball of sodium to go sizzling across the SURFACE of the water. Explanation: |
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| 29. |
How chlorine mass no is 37 ? it is only 35 ... |
Answer» Chlorine MASS no. is 37 not 35 because it is compound, and compound's COMPOSITION is FIXED.HOPE IT HELPS YOU................. |
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| 30. |
atwhite powdery x immediately turned into a hard mass on adding a liquid y to it.in hospital athick coat of the paste of the substance x is appliedto the bandage on a factured bone of the patient to keep the bone in a place to get joined .what would be the substance name the liquid y in on x adding y |
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| 31. |
Identify the substances that are oxidized and reduced in the following reaction:a. Fe2O3 + 2Al---Al2O3 + 2Fe b. 2PbO + C---2Pb + CO2 |
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| 32. |
What is the relation between atomicity and vont Hoff factor |
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Answer» Answer: Van't Hoff factor i, determines the extent of association or DISSOCIATION, which can lead to ABNORMAL molar MASS of a substance. It can be calculated as: Now in case of octa-atomic molecule, 8 atoms combine to FORM a molecule. Therefore, the NUMBER of particles before association are 8 and after particles are |
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| 33. |
Q. No 21..plz help me in this |
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Answer» Answer: (c) CHCl3 Explanation: as we know that C-H BONDS are non polar , the dipole moment depends on the more electro negative atom i..E, Cl therefore more the NUMBER of Cl atoms , more the polarity but in OPTION (D) the dipole moments ( directed from Cl to C ) will get cancelled to each other as CCl4 is tetrahedral now comparing option (b) and (c) , we have more Cl in (c) than (b) therefore option (c) is correct as PER the above explanation |
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| 34. |
What are the uses of bhc? |
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Answer» Answer: BHC is an important AGRICULTURAL pesticide MAINLY USED for exterminating white ants, leafhopper, termite ETC. |
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| 35. |
Which of the following is incorrect about kmno4(a) it is very dark purple black solid(b) it forms rhombic prisms (c) the intense purple colour of permanganate ion arises from d-d transition (d) it is fairly soluble in water |
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| 36. |
Orthophosphoric acid isa) monobasic acidc) Tribasic acidb) dibasic acidd) tetrabasic acid |
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Answer» THE ORTHOPHOSPHORIC ACID ARE DIBASIC ACID MARK AS BRAINLIST |
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| 37. |
What is C40 H30 N2O4 means ? |
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Answer» Answer: EN 1.0511 (C40) Non-Alloy Steel. EN 1.0511 steel is a carbon (non-alloy) steel formulated for primary forming into WROUGHT products. CITED PROPERTIES are appropriate for the normalized condition. 1.0511 is the EN numeric designation for this material. C40 is the EN chemical designation. Explanation: |
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| 38. |
Hybridisation defination |
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Answer» HYBRIDIZATION is a technique UESD for developing new varieties of crops by cross breeding TWO different varieties.
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| 39. |
Match the followingBCI,Sio,CO,A. Angular moleculeB. linear covalent moleculeC. Tetrahedral molecule 2)D. Planar trigonal molecule 1). |
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Answer» BCL is. Planar trigonal molecule SiO Tetrahedral molecule |
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| 43. |
K35° > 1, this means thatk34(1) Rate increases with the rise in temperature(3) rate does not change with rise in temperature(2) Rate decreases with rise in temperature(4) None of the above |
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Answer» k35° > 1, this means that k34? |
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| 44. |
The structure of intermediate A in the following the reaction is : |
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Answer» I don't UNDERSTAND the QUESTION |
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| 45. |
which one of the following set of quantum numbers is not possible for an electron in the ground state of an atom with atomic number 19 |
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Answer» Answer: ELECTRON AFFINITY of nitrogen is lower(less negative ) than carbon. ... For many elements ,ENERGY is released when an electron is added to the atom and therefore , electron gain enthalpy is negative. The magnitude of the electron gain enthalpy measures the ability of an atom to hold an ADDITIONAL electron . |
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| 46. |
The enthalpy of formation of the compound isa) always positive b) always negativec) can be positive or negative d) unpredictable |
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| 47. |
Which of the following compounds is used as thebest anti-knocking agenta) Tetraeth leadb) methanec) methoxypropune d) methyl cyanide |
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Answer» Answer: a) Tetraeth lead Explanation: The organic COMPOUND that is used as an antiknock agent is TETRAETHYL lead. This is a lead based organic compound. Antiknock agents are gasoline additives that HELP in lessening the engine knocking and increasing the octane rating of the fuel at the same TIME. |
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| 48. |
Chloro benzene on treatment with sodium in dry ether gives diphenyl. the name of the reaction is |
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| 49. |
Which has smallest size ..nitrogen or oxygen |
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Answer» Answer:Oxygen Explanation: Because it has eight electrons in its shells. The eight PROTONS in oxygen atom's NUCLEUS will exert more force than nitrogen's seven electrons. ALSO, oxygen has same NUMBER of shells as nitrogen. ... When electrons are closer it means atomic radius is smaller. |
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