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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. |
Copper is a good conductor of electricity because its electrons |
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Answer» Answer: The electrons can move freely through the metal. For this reason, they are known as free electrons. They are also known as CONDUCTION electrons, because they help copperto be a good conductor of heat and ELECTRICITY. ... When anelectric current flows in a wire, the electrons move through the wire. Explanation: Metals are good conductors of Heat and electricity. Because metals allow heat and electricity to PASS through them easily. |
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| 2. |
Concentrated sulphuric acid in a test tube changes to blue on adding small piece of copper on it |
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Answer» Answer: Yes Explanation: It is so because when metal reacts with acid it forms basic oxide so copper pieces ACT as indicator and show that when metal reacts with acid it forms basic oxide. Often when you dip red litmus PAPER in acid with metal it CHANGES its colour into blue. |
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| 3. |
Conversion of 4-aminoacetophenone to 4 acetyl phenyl sulfonyl chloride reaction |
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Answer» Answer: Explanation: The direct ACETYLATION of 4-hydroxycoumarin 1 with ACETYL chloride using ... REACTION of 4-methyl-2-phenyl-2-oxazolin-5-one 101 with 4-hydroxycoumarin 1 ...... A.R. BUTLER, E.H. BrownCondensation of 2-hydroxy-2′-aminoacetophenone to form a ..... improved SYNTHESIS of 4-chlorocoumarin-3-sulfonyl chloride and its reactions ... |
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| 4. |
Conductivity of silicon increases by doping it with group 15 elements |
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Answer» Answer: Explanation: SI FORM n TYPE semiconductor with the elements of grp 15 and the conductivitu is due to the PRESENCE of an extra ELECTRON |
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| 5. |
If you have a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.a. Do you think rust is different from iron? What type of change it is?b. Can you change rust back into iron by some simple method?c. Give two other examples of a similar type of change.please tell the answer quickly I will mark you as BRAINLIST |
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Answer» A- It is a SLOW change and DIFFERENT from Iron. B- YES a.By rubbing SAND PAPER b.by polishing C- 1-Ripening of fruits 2-Growth of Plants |
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| 6. |
Chlorine gas is passed through slaked lime balance chemical equation |
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Answer» Explanation: when chlorine gas is PASSED in slaked LIME then CALCIUM OXYCHLORIDE is formed.i.e, ca(oH)2+cl2=caocl2 where ca(oH)2=calcium hydroxide cl2=chlorine gas caocl2=calcium oxychloride this is your answer.☺️ |
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| 7. |
Difference between inorganic carbon and organic carbon |
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Answer» Answer: difference between INORGANIC and organic carbon is that the inorganic carbon is the carbon EXTRACTED from ores and minerals whereas the organic carbon is found in nature from plants and living THINGS. |
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| 8. |
Difference between graphite oxide and graphene oxide |
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Answer» Answer: Graphite oxide and GRAPHENE oxide are very similar, chemically, but structurally, they are very different. The main difference between graphite oxide and graphene oxide is the interplanar SPACING between the individual atomic LAYERS of the compounds, caused by WATER intercalation. |
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| 9. |
Difference between chemical properties of acids and bases |
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Answer» Answer: DIFFERENCE BETWEEN ACID AND BASESThe strength of acids depends on the concentration of hydronium ions while the strength depends on the concentration of hydroxide ions. Acids DISSOCIATE to give free hydrogen ions (H+) when mixed in WATER, whereas bases dissociate to give free hydroxide ions (OH–) when mixed in water. PLEASE IF U LIKE MY ANSWER THAN PLS FOLLOW ME |
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| 10. |
Please give the answer with deatails |
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Answer» Answer: CHECK the attachment... hope this HELPS... MARK it as brainliest please!! |
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| 11. |
Whathappens when you add magnesium + zinc sulphate |
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Answer» MAGNESIUM SULPHATE and ZINC is formed magnesium DISPLACES zinc from zinc sulphate |
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| 12. |
In reference to freundlich adsorption isotherm write expression for adsorption of gases on solids in the form of an equation |
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Answer» X/m PROPORTIONAL to P1/n |
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| 13. |
In the presence of an acid the initial concentration of cane sugar |
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Answer» In the presence of an ACID the initial CONCENTRATION of cane sugarwas REDUCED from 0.2M to 0.1 in 5hrs and to 0.05M in 10hrs |
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| 14. |
In case of bonding molecular orbital electron density is located at |
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Answer» Answer: bonding orbital is used in MOLECULAR orbital (MO) theory to DESCRIBE the attractive interactions between the atomic orbitals of two or more ATOMS in a molecule. In MO theory, electrons are portrayed to move in waves. When more than one of these waves come close together, the in-phase combination of these waves produces an interaction that leads to a species that is greatly STABILIZED. The result of the waves’ constructive interference CAUSES the density of the electrons to be found within the binding region, creating a stable bond between the two species. |
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| 15. |
Calculate the number of spectral lines when an electron return from 7 orbit to balmer series |
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| 16. |
Calculate the no. Of carbon and oxygen atom in1.06 grams of sofium carbonate |
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| 17. |
Can you separate a mixture of salt and sand byhand picking ?If not give method its separation |
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Answer» No First we have to MAKE a solution of the mixture.Then FILTER it USING a filter.The SAND is SEPARATED. |
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| 18. |
Calculate the second ecitation energy of the electron in the hydrogen atom |
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Answer» Explanation: n = 3 ( since it is second excited state) Z = 1 E = -13.6 × Z^2/n^2 = -13.6 ×1^2/3^2 = -13.6/9 = -1.51eV Here is your ANSWER . Follow me and mark my anawer as brainliest PLEASE. |
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| 19. |
Calculate the number of electrons protons and neutrons present in 81g of al^3+ |
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Answer» Firstly we write the Atomic Number of ALUMINUM atom ,that is 13 so Number of PROTON =13 Number of Electron =13 Number of NEUTRON =14 Then According to question 3 ELECTRONS are remove so , Number of Proton=13 Number of Electron =13-3=10 Number of Neutron=14 |
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| 20. |
Calculate the molal elevation constant. On for water and the boiling point of 0.1 molal urea solution |
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Answer» Answer: Latent HEAT of vaporization of water is 9.72kcalmol1 at 373.15k. ... latent heat of vaporisation, L = 9.72 Kcal/g = 9720 cal/mol. ... so, BOILING POINT of urea solution is (373.15 + 0.0515)K. |
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| 21. |
Di9ff between lactic acid and alcholicic fermentation |
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Answer» Answer: Explanation: Lactic ACID and ALCOHOLIC fermentation are TWO mechanisms involved in the respiration in the absence of oxygen. Both types of fermentation occur in the CYTOSOL. ... Lactic acid fermentation produces lactic acid molecules from PYRUVATE while alcoholic fermentation produces ethanol and carbon dioxide from pyruvate |
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| 22. |
Iexplainwhile cl.mg. with slowlyis react radiallyand |
Answer» Can you WRITE the QUESTION in CORRECT MANNER............ |
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| 24. |
In an excited hydrogen atom emmission spectrum contains 10 emmission lines what is the lowest orbit in which the electron is expected to be found is |
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Answer» Answer: The number of spectral linesproduced when an electron in the nthlevel drops down to the GROUND state is given by n(n-1)/2. The energy associated with the FIRST orbit in thehydrogen atom is –2.18×10-18 J atom-1. hope it help U |
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| 25. |
In an atom the energy of the electron decreases as the value of n increases |
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Answer» Answer: ENERGY 1 / ∝ DISTANCE Explanation: WE know that in an atom the closer the elctron is to the nucleus the more energy it will have . since it will face more force and energy NEAR the nucleus. ∴ ENERGY 1 / ∝ DISTANCEso here the electron has moved AWAY the energy has decreased |
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| 26. |
Calculate the energy associated with first orbit of h e plus full stop |
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Answer» E = -13.6Z²/n² eV For first ORBIT if He+ Z = 2 and n = 1 E = -13.6 × 2^2 / 1^2 E = -54.4 eV Energy associated with first orbit of He+ atom is -54.4 eV
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| 27. |
Boron ocuursas b10 and b11 in natuer average atimic mass of boron is 10.804 what is the natural abundance of b11 isotopes |
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Answer» Answer: b¹1 has more abundance in naturw with 80.4% % abundance of b-10 be x % abundance of b-11 be (100-x) 10*x+11(100-x)/100=10.804 10x+1100-11x=1080.4 -x=1080.4-1100 =19.6 % abundance of b-10 be 19.6% % abundance of b-11 be (100-19.6)=80.4% |
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| 28. |
Bod5 refers to 5 days of decomposition at 20c. If temperature is increased to 35c,then the 5 day bod can be obtained by |
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Answer» what is BOD ???? i can't UNDERSTAND |
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| 29. |
Describe the process of sodium hydroxide from salt soluiton |
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Answer» Explanation: SODIUM hydroxide is produced using a salt water brine. The sodium and chloride are separated. ELECTRONS from chloride are COLLECTED at the anode where it combines into CHLORINE gas. These electrons are USED to separate water into hydrogen gas and hydroxide. |
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| 30. |
Derive the equation for rate of a first order reaction |
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Answer» dt8xtoxoychphpphcpy Explanation: 8tsr8zr8t0d0yft9c9tx |
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| 31. |
8. What happens when the magnesium oxide is mixed with water. The product obtained is acidic or basic? Howwill you prove it? Write the equation for the reaction?please tell the answer quickly I will mark you has BRAINLIST |
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Answer» Answer: When magnesium dioxide is mixed with WATER then magnesium hydroxide is formed and hydrogen gas evolved................The product will be basic....we PROVE it by TESTING the product with litmus (RED) and it CHANGES it to blue ,showing it is basic |
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| 32. |
The gases contain 1022 and 1023 moleculespresent in different vessels at the sametemperature. The ratio of their average K.E.is1) 1:10 2) 10:1 3) 1:1 4)1:5 |
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Answer» i.e.1:5 |
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| 33. |
Slate the following statements into chemical equations and then balance the equations(a) Hydrogen sulphide gas burns in air to give water and sulphur dioxide.(b) Phosphorus burns in oxygen to give phosphorus pentoxide.(c) Carbon disulphide burns in air to give carbon dioxide and sulphur dioxide.(d) Aluminium metal replaces iron from ferric oxide, FexOy, giving aluminium oxide and iro(C) Barium chloride reacts with zinc sulphate to give zinc chloride and barium sulphate. |
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Answer» Answer: 2H2S + 3O2 - 2H2O + 2SO2 P4 + 5O2 - 2P2O5 C2S + 3O2 - 2CO2 + SO2 2AL + FE2O3 - AL2O3 + 2FE BACL2 + ZNSO4 - ZNCL2 +BASO4 Explanation: |
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| 34. |
9. How will you indicate the following effect in s chemical reaction(a) A solution made in water(b) Exothermic reaction(c) Endothermic react |
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Answer» a)if the PH of the solution is neutral b)if HEAT is released |
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| 35. |
If the shortest wavelength of layman series of h atom is x.Then wavelength of 1st line of balmer series of h atom will be |
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Answer» answer is = (36 /5)X . Explanation: REFER ATTACHMENT for explanation. |
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| 36. |
A zinc ore gave co2 on treatment with dilute acid identify the ore and write its chemical formula |
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Answer» The ORE is calamine. It's COMMON NAME is zinc carbonate. It's formula is ZnCO3. Hope it helps you. |
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| 37. |
If the radius of first bohrs orbit be alpha then the radius of the 3rd orbit of hydrogen would be |
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Answer» Answer: If the radius of FIRST Bohr orbit of hydrogen atom is 'x' then DE BROGLIE WAVELENGTH of electron in 3rd Orbit is nearly. (a)2πx(B)6πx(c) 9x(d)x3. |
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| 38. |
At which stage of mitotic chromatids seprated and passes to different poles |
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Answer» during anaphase, the centromeres holding the sister CHROMATIDS together are divided and the sister chromatids are pulled APART by the spindle fibers to opposite POLES of the diving cell. During the last phase of mitosis, telophase, the two sets of CHROMOSOMES reach the poles of the cell. |
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| 39. |
At what temperature is average speed of gas molecule will be double than that at 27 |
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Answer» Explanation: ANSWER: We KNOW, Average speed, V=√(8R*T/πM). At 27 C. V1= √(8R*27/πM). Let V2 be the speed which is DOUBLE of V1 so, V1/V2=√(8R*T/πM)/√(8R*27/πM). 1/2=√27/√T2. Squaring on both the sides we get, T2=27*4. T2=108 C. |
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| 40. |
Define order of reaction and activation energy of reaction |
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Answer» Explanation: The term ACTIVATION ENERGY was introduced in 1889 by Svante Arrhenius, a Swedish scientist. Hope it will help you... Please make me brain list.... |
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| 41. |
21.On heating calcium carbonate gets converted into calcium oxide and carbon dioxide.(a) Is this a physical or a chemical change?(b) Can you prepare one acidic and one basic solution by using the products formed in the above processIf so, write the chemical equation involved. |
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Answer» Answer: i. it's a chemical change ll. Yes Explanation: i. Because NEW substance are FORMED according to the DEFINITION of chemical change ii. CaO is formed ALONGSIDE CO2 the equations are CaO + H2O - Ca(OH)2 which is basic CO2 + H2O - H2CO3 which is acidic
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| 42. |
WHAT DO YOU MEAN BY VOLATILE? |
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Answer» Answer: it's a SUBSTANCE which EVAPORATES EASILY under NORMAL temperatures |
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| 43. |
If the radius of first bohr orbit is r then radius of second bohr orbit is |
Answer» Hey mater = 0.529 n^2/Z Radius for second bohr orbit n=2 r" = 4 And Radius of FIRST bohr orbit is n = 1 r' = r therefore Radius of second Bohr orbit is 4r hope this will help UH! |
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| 44. |
If the radius decreass by 20% ehat wll be the percentage of change in value of g |
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Answer» Explanation: The simple ANSWER is that it will INCREASE. But we can FIND out by how much. 10% of earths radius would be 637,100 m which would MAKE the new radius 5,733,900 m (6,371,000-637,100). |
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| 45. |
If the radius of first bohr orbit of hydrogen atom is x then the de broglie wavelength of third bohr orbit of li2+ is |
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Answer» Explanation: FIRST excited state of ATOMIC HYDROGEN. ... Calculate the de Broglie wavelength. 18. ... The angular momentum of an electron in a Bohr's orbit of H-atom is 3. 1 624 x 10~34 KG m2/sec. |
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| 46. |
A student has been collecting silver and copper coins one day she observe a black coating on silver and a green coating on copper coins which chemical phenomenon is responsible for these coating write the chemical names of black and green coatings |
Answer» Answer: this due to OXIDATION of COPPER and silversilver oxide and copper oxideExplanation: When exposed copper will REACT with atmospheric oxygen .. 2Cu + O₂ ⇒ 2CuOTHIS GIVES US THE GREENISH OXIDE OF COPPER. When exposed silver will react with atmospheric oxygen .. 2Ag + O₂ ⇒ Ag₂OTHIS GIVES US THEBLACK OXIDE OF SILVER. |
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| 47. |
Atom is exposed to electromagnetic radiation of 1026 angstrom and gives out induced radiation radiation emitted electron returns to ground state calculate lambda of induced radiation |
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Answer» the answer is here Explanation: |
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| 48. |
A short dipole of dipole moment 4 microcoulomb is placed at origin |
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Answer» it will be 4 only MICROCODE and I can ALSO do it I have to GAIN |
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| 49. |
The angular momentum of electron in 'd' orbital isequal to[AIPMT-2015](1) 0 h(2) √6(3) √2h(4) 2√3 h |
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Answer» the ANSWER of this is nh/2×22/7 |
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