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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. |
how many moles of gases are present in a 10 litre sample of standard temperature and pressure system |
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Answer» ................................................................ |
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| 2. |
Which type of colloids are formed when dispersing medium and dispersed phase both are liquid |
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Answer» emulsion is formed when the dispersing MEDIUM and dispersed PHASE both are liquid |
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| 3. |
The density of 3 (M) NaOH solution in water is1.2 g/ml. The mole fraction of NaOH is(A)0.013(B) 0.53(C) 0.038(D) 0.047 |
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Answer» density=mass/volume density*volume=mass 1.2g=mass no. of MOLES of water=.066 moles of naoh=3 mole fraction=3/3.066 =.9784 |
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| 4. |
Mechanism of cumene to phenol preparation |
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Answer» Answer: This is an OLD industrial PROCESS. Cumene (isopropylbenzene) is OXIDIZED with air in the presence of a cobalt catalyst. The product is cumene hydroperoxide, which is to say PhCMe2OOH. When the hydroperoxide is heated in dilute sulfuric acid, it FRAGMENTS into phenol and acetone, both of which are sold. This process has fallen out of favor compared to other MANUFACTURING routes. The problem is that phenol and acetone are formed in a fixed ratio and the market demand for the two products does not necessarily match. |
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| 5. |
------------ are waves used by cops to test the speed of your car with radara)uvb)infraredc)radiodmicrowaves |
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Answer» Answer: |
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| 6. |
Em waves in which our eyes are sensitive to a.infrared b.light c.uv d. gamma |
| Answer» SORRY I don’t KNOW but you can SEARCH on GOOGLE | |
| 8. |
Write laboratory prepration and physical and chemical prperties of dihydrogen also uses. plz tell |
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Answer» It is colourless, tasteless, ODOURLESS gas. It has extremely LOW solubility in water. Since its molecules are non-polar. Its DENSITY is approximately 1/4th that of air. ... It can be LIQUEFIED at high pressures and very low temperature. It is highly combustible and should be handled with care. Explanation: |
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| 9. |
Define length and what is the unit of length |
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Answer» Length is a measure of distance. In the International SYSTEM of Quantities, length is any QUANTITY with DIMENSION distance. In most systems of measurement, the UNIT of length is a base unit, from which other units are derived. |
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| 11. |
Plays important role in wireless communicationa)uv raysb)visible raysc)infraredd)microwave |
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| 12. |
What are the properties of Chlorine, Hydrogen and sulphur dioxide? |
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Answer» Answer: SULFUR Dioxide FORMULA SO2 Molecular WEIGHT (lb/mol) 64.06 Critical Temp. (°F) 315.5 Critical Pressure (psia) 1142.0 Boiling Point (°F) 14.3 Melting Point (°F) -103.9 Psat @ 70°F (psia) 49.3 Liquid Density @ 70°F (lb/ft3) 85.98 Gas Density @ 70°F 1 atm (lb/ft3) 0.1682 Specific Volume @ 70°F 1 atm (ft3/lb) 5.94 Specific Gravity 2.285 Specific HEAT @ 70°F (Btu/lbmol-°F) 9.58 |
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| 13. |
Preparation collection and study of some important physical and chemical properties of at least three gases , one each from the following groups : 1 hydrogen and oxygen, 2 carbon dioxide and hydrogen sulphide, 3 chlorine ,hydrogen, and sulphur dioxide ? solution |
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Answer» Answer: 1. Hydrogen Hydrogen is prepared in the LABORATORY by reacting acid with metals. It is collected over water as hydrogen is sparingly soluble in water. Hydrogen is the smallest element in the periodic table. Hydrogen is non-toxic, nonmetallic, odorless, tasteless, colorless gas. Hydrogen is highly flammable. The enthalpy of combustion is -286kJ/mol. 2. Carbon dioxide Carbon dioxide is a colorless gas. It is odorless at LOW concentration but has a sharp and acidic SMELL at high concentration. Carbon dioxide reacts with water to give CARBONIC acid. Carbon dioxide reacts with alkali to give CARBONATES and bicarbonates. Carbon dioxide is produced by reacting acid with carbonate. Calcium carbonate and hydrochloric acid are generally used. It is collected over the water. 3. Chlorine Chlorine is a greenish-yellow gas with a pungent choking smell. It is moderately soluble in water. Chlorine is a highly corrosive and toxic gas. It reacts with metals upon heating to give salt. Chlorine is generally prepared by heating manganese dioxide with concentrated hydrochloric acid. Chlorine is collected in an airtight container.
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| 14. |
Value of dipole moment if covalent bond has 25% ionic character |
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Answer» The dipole moment of HF is μ = 1.82 D, and the bond LENGTH is 92 PM. Calculate the percent ionic CHARACTER of the H-F ... |
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| 15. |
6.5g of an impure sample of limestone liberates 2.2g of CO on strong heating. The percentage purity of CaCo in the sample is |
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Answer» Amount of CO2 liberated = 2.2 gm |
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| 16. |
How does an atom differ from molecule |
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Answer» Answer: ATOMS are MADE up of two or more MOLECULES bonded covalently. C) Molecules are made up of only one ELEMENT. ... Atoms are made up of two or more molecules bonded covalently. C) Molecules are made up of only one element. D) Molecules are made up of two or more atoms bonded covalently. |
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| 17. |
Anyone ans my question red to blue tk likho plz .i can't understand |
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Answer» hey MATE please refer to the ATTACHMENT, ur answer is 12.228997 in ROUND figure it is 12.229 |
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| 18. |
Find the number if orbitals for the following set of quantum numbers:n=2,=3,m1=-2 |
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Answer» ANSWER: 0 Explanation: |
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| 19. |
What is hydrogen bonding |
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Answer» HELLO MATE ! A HYDROGEN bond is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. This is not a sharing of electrons, as in a covalent bond. Instead, this is an attraction between the POSITIVE and negative poles of charged atoms. |
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| 20. |
How many grams of NaOH are present in 250 cm3of 0.5 (M) NaOH solution ?(A) 10 gm(C) 5 gm(D)4 gm(B)20 gm |
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Answer» Answer: Molarity= No. ofMoles of solute/VOLUME of the solution in litres. So,given INFO- 0.5(M)=Molarity and volume given as 250cm^3 BTP:- 0.5 =Moles/250×1000 Moles=0.5×25000 =12500 Mass of NaOH= 12500×Molecular mass =12500×40 =5×10^5 HOPE THIS HELPS.. |
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| 21. |
The mass of one unit cell of NaCl is |
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Answer» ONE unit cell of NaCl contains 4 NaCl units (ie) has mass Number of unit cell PRESENT in a cube shaped crystal of NaCl of mass 1 g = m×Na(M×Z) HENCE Z = 4 Molecular Weight of NaCl (M) = 58.5 m = 1.00 g Na=6.023×1023 Hence substitute the value in the above equation We get No. of unit cell in 1g =1×6.02×10234×58.5 ⇒2.57×1021 |
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| 22. |
5 examples of reversible chemical change. |
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Answer»
CHEMICAL CHANGE is IRREVERSIBLE........
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| 23. |
Write laboratory prepration and physical and chemical properties of dihydrogen also uses |
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Answer» In the LABORATORY, H2 is USUALLY prepared by the reaction of acids on metals such as ZINC with Kipp's apparatus. The electrolysis of water is a SIMPLE method of producing hydrogen. |
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| 24. |
Red mark se blue mark tak koi jante ho to plz likh do.i can'n understand plz plz .glt mt dikhana |
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| 25. |
Equilibrium: Please solve the question in the image. Ans. is 0.66 M but I need the solution. THANKS A LOTWILL MARK BRAINLIESTTROLLERS WILL BE REPORTED IMMEDIATELY |
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Answer» Answer: The reaction STARTS when the tap is open . So, when the tap OPENS the volume of the actual mixture will be = 1+3 = 4 lt. so, the initial concentration of a is = moles of a /vol. of solution (in lt) = 2/4 = 0.5 mole the initial concentration of b is = moles of b/vol.of solution (in lt) = 4/4 = 1 mole a2 + b2 - 2ab at t=0 = 0.5 1 0 at t=equilibrium = 0.5 -X 1-x 2X kc = (2x)^2/(0.5-x)(1-x) GIVEN that kc = 4 solve this you get x = 0.33 but as you see that at equilibrium the concentration of ab is 2x hence , the required answer is 2*0.33 = 0.66 moles |
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| 26. |
Describe an experiment to make copper sulphate crystals from its solution?PLEASE TELL THE ANSWER... |
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Answer» Explanation: Place some sulfuric acid in a CONICAL flask and WARM it in a water bath. Add a SPATULA of copper oxide powder to the acid and stir with a glass rod. Continue adding copper oxide powder until it is in excess . Filter the mixture to REMOVE the excess copper oxide. |
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| 27. |
What is fractional distillation |
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Answer» Answer: separation of a LIQUID mixture into fractions DIFFERING in boiling point (and hence chemical composition) by means of distillation, typically using a FRACTIONATING column. |
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| 28. |
The atomic number of elements A and B respectively are 4 and 17. What is the type of bond formed between A and B ?1. Ionic2.Covalent3. Polar covalent4. CoordinatePleas give reason too for your answer!!! |
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| 29. |
The average velocity of CO2 at T K is 9×10^4 cm/s. The value of T is? |
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| 30. |
Write laboratory prepration and physical and chemical properties of dihydrogen also its uses ??? |
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| 31. |
What could be used as a detector of infra-red radiations?a)your handb)a microphonec)a parabolic reflectord)microscope pls do answer it fast |
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Answer» c) a PARABOLIC reflector Explanation: mark me the BRAINLIEST answer PLEASE |
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| 33. |
What is a carding define it |
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Answer» Carding is a form of credit card FRAUD in which a stolen credit card is USED to charge prepaid cards. Carding typically involves the holder of the stolen card purchasing store-branded gift cards, which can then be sold to OTHERS or used to purchase other goods that can be sold for CASH. |
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| 35. |
If the magnetic moment of a cation MX + having or atomic number equal to 25 is under root 15 BM then calculate the value of x |
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| 36. |
Organic chemistry easy h ????? |
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Answer» Explanation: ha EASY ha |
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| 37. |
What is diffrence between element and compound |
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Answer» Answer: COMPOUNDS contain atom of DIFFERENT ELEMENTS chemically combined TOGETHER in fixed ratio. an element is pure CHEMICAL substances made up same type of atom. Mark me as brainliest |
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| 38. |
B) Calculate the frequency of an alternating current if thedirection changes after every 0.01sec? |
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Answer» Answer: 50 Explanation: n=1/t here,t=0.02s t=time PERIOD . so n=50Hz |
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| 40. |
which of the following will contain same number of molecules as 40 gram of O2 A 55 gram of co2 b. 34 gram of NH3 c 64 gram of So2 and option d. 73 gram of HCL |
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Answer» Answer: Explanation: MOLES= 40/32 =5/4 now moles of CO2 = 55/44 = 5/4 |
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| 41. |
Iron articles are many times coated with Zinc.a. What is this process known as and define the processb. How is this process beneficial?c. Write one application of this method?PLEASE TELL THE ANSWER.. |
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Answer» Answer: a.this process is CALLED galvinization b.it PREVENTS the metal from rusting or corrosion |
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| 42. |
Reactivity series of metals and arrange the metals in increasing or decreasing order |
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Answer» Explanation: The Arrangement of metals in the DECREASING order of their reactivities is CALLED the ACTIVITY series of metals. |
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| 43. |
What is the formula for the revolution of electrons per second in an Orbit |
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Answer» DIVIDING the two EQUATIONS we get ,. Number of REVOLUTION PER SECOND by electron in 3rd orbit of HNumber of revolution ... |
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| 44. |
Explain the particles other than fundamental particle present in an atom.?? |
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| 45. |
Define Bond energy of an atom. |
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Answer» ❤️❤️✌️✌️❤️❤️ ➡️The ENERGY REQUIRED to dissociate any BOND is known as bond energy. It depends on FOLLOWING factors :⤵️ ➡️Bond order. ➡️'s' character. ➡️Resonance. ➡️Bond length. ❤️Follow me❤️ ✌️Inbox✌️☺️ |
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| 46. |
Find the odd one out winnowing,decantation,filtration,distillation give reason in short |
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Answer» Explanation: Winnowing, because this PROCESS is used for CLEARING solid SUBSTANCES while OTHERS are used for clearing liquids |
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| 47. |
Why concentrated sulphuric acid or hydrochloric acid is not used for preparation of hydrogen gas in the laboratory? |
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Answer» <STRONG>Explanation: Both the acids are quite strong as when we test their PH levels they range between 0-1 which MAKE it highest RANKED ACID which can dissociate maximum H+ ions on dissolving with water and also HCl or H2SO4 acid not used in the laboratory preparation of hydrogen. |
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| 48. |
An iron pan was left open in a moist place for 2-3 days:a. What will you observe after 3 days?b. Name the substance formed?c. What will happen if we keep it in the moist atmosphere for several days?PLEASE TELL THE ANSWER |
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| 49. |
The important properties of a compunds |
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Answer» Explanation: A compound has unique properties that are distinct from the properties of its elemental constituents.One familiar chemical compound is water ,a LIQUID that is NONFLAMMABLE and does not support COMBUSTION.it is COMPOSED of two elements :hydrogen ,an extremely flammable gas ,and oxygen ,a gas that support combustion. |
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| 50. |
How many grams of copper must be taken to get 1 mole of elements |
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Answer» 0.157 is answer |
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