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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. |
Who introduced mole |
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Answer» Wilhelm Ostwald The name MOLE is an 1897 translation of the German unit mol , coined by the chemist Wilhelm Ostwald in 1894 from the German word molekul ( molecule ) .however , the related concept of equivalent mass had been in USE at least a century earlier . |
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| 2. |
4. Ions needed for nerve conduction :-(1) Na(2) Ca+(3) Mg++(4) Nonewith reason why notCa+ |
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Answer» Na+ because Na has one VALENCY and it only takes 1 electron for NERVE CONDUCTION so not Ca+ |
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| 5. |
The atomic number of three elements are 5,7 and 10 respectively.which if these: 1 belong to group 18 .2 belong to group 15 .3 belong to group 13 |
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Answer» Answer: 10 BELONGS to 18th GROUP,7 belongs to group 15 and 5 belongs to 13th group Explanation: by making ELECTRONIC CONFIGURATION where subshell filled with electrons then its a NOBLE gas and rest you can find by e.c |
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| 6. |
Reaction between copper sulphate and KCN is |
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Answer» Copper SULPHATE REACTS with KCN to form cupric cyanide which PRECIPITATES out FIRSTLY |
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| 7. |
Lesson physical and chemical changes. Name a change that is useful to us |
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Answer» CHEMICAL changes Explanation: |
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| 8. |
What is plastic ?jaldi batao |
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Answer» Answer: It is a non-biodegradable SUBSTANCE OR |
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| 9. |
Write any 3 difference between Chemical change and physical change |
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Answer» my account on it emiti SIR cheppindi EMI tante me madam I am a bit of the week of MAY be a GOOD |
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| 10. |
Why sulphuric acid is added while making the crystals of copper sulphate |
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Answer» Answer:When CRYSTALS of copper sulphate are DROPPED into sulphuric acid then the copper sulphate will LOSE its water molecules as sulphuric acid is a dehydrating agent RESULTING in the formation of a SOLID copper sulphate. This solid copper sulphate will be ahnydrous hence it will be white in color. |
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| 12. |
Is the definition given for ionization enthalpy is correct? "IONIZATION ENTHALPY IS DEFINED AS THE ENERGY REQUIRED TO REMOVE THE MOST LOOSELY BOUND ELECTRON FROM THE VALENCE SHELL OF AN ATOM" ....If not, what is the correct definition? |
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Answer» Answer: Explanation: Ionization ENERGY is the energy required to remove an electron from a GASEOUS atom or ion. The FIRST or initial ionization energy or Ei of an atom or MOLECULE is the energy required to remove one mole of ELECTRONS from one mole of isolated gaseous atoms or ions. |
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| 13. |
you are provided with a mixture of Ammonium Chloride and sodium chloride suggest an activity to prepare them with the well labelled diagram |
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Answer» this PROCESS can be DONE through SUBLIMATION |
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| 14. |
What is ment by "inflammable substance" |
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Answer» INFLAMABLE SUBSTANCE are those substance which can catch fire EASILY or RAPIDLY. |
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| 15. |
Which of the following is a true solution and water starch sugar chalk powder egg albumin |
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| 16. |
Calculate the number of atoms in 8 gram of oxygen molecules? |
Answer» @HEY!!REFER to ATTACHEMENT ⤴ Thanks |
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| 17. |
Which of the following gives the true solution in water starch sugar chalk powder egg albumin |
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| 18. |
If vapour pressure is very low so why vacuum creates in a tube |
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Answer» Answer: The Barometer Barometer is used to determine the local atmospheric pressure. Mercury is employed in the barometer because its density is sufficiently high for a relative short column to be obtained. and also because it has very small vapour pressure at normal temperature. High density scales down the pressure head(h) to repesent same magnitude of pressure in a tube of smaller HEIGHT. Click to play the demonstration Fig 4.3 A SIMPLE Barometer Even if the air is completely absent, a perfect vacuum at the top of the tube is never possible. The space would be occupied by the mercury vapour and the pressure would equal to the vapour pressure of mercury at its existing temperature. This almost vacuum condition above the mercury in the barometer is known as Torricellian vacuum. The pressure at A equal to that at B (Fig. 4.3) which is the atmospheric pressure patm since A and B lie on the same horizontal plane. Therefore, we can write (4.1) The vapour pressure of mercury pv, can normally be neglected in comparison to patm. At 200C,Pv is only 0.16 patm, where patm =1.0132 X105 Pa at sea level. Then we GET from Eq. (4.1)
For accuracy, small corrections are necessary to allow for the variation of r with temperature, the thermal expansion of the scale (usually made of brass). and surface tension effects. If water was used instead of mercury, the corresponding height of the column would be about 10.4 m provided that a perfect vacuum could be achieved above the water. However, the vapour pressure of water at ordinary temperature is appreciable and so the ACTUAL height at, say, 15°C would be about 180 mm less than this value. Moreover. with a tube smaller in diameter than about 15 mm, surface tension effects become significant. |
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| 19. |
calculate the percentage composition in terms of the mass of a solution obtained by mixing 300 grams of 25% and 400 gram of 40% solution of mass |
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Answer» Explanation: total mass of SOLUTION, (M) = 300+400 = 700 GRAM mass of solute in solution 1 = (300*25)/100= 75 gram mass of solute in solution 2 = (400*40)/100= 160 gram total mass of solute (m)= 75+160 = 235 gram solute % (by mass ) in solution = (m/M)*100 = (235/700)*100= 33.57 % solvent % (by mass ) = 100-33.57 = 66.43 % |
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| 20. |
F. What is the SI unit of amount of asubstance ?G. What is meant by molar volume of agas? |
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Answer» S.I unit of amount of a substance is mol. Molar VOL. is simply 22.4L PRESENT in 1 mol at STP (but according to NCERT it is NTP) |
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| 21. |
Important characteristic of Gaseous state is/area) Contains very weak intermolecular forces of attractionb) Highly compressiblec) Tharmal energy is maximumd) All the above |
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Answer» D) All of the above . |
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| 22. |
Example of explosion full example |
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| 23. |
If MALE =12 and FEMALE=30 then how will you code WOMAN |
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Answer» Answer:20 HOPE IT HELPS YOU!!! THANK YOU!!! |
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| 25. |
Example of explosion full answer |
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Answer» Answer: Examples of explosions are....
U must have seen hand grenade exploding U EAT popcorns...... Its a good example Even a SMALL spark in matchsticks is an EXPLOSION Thnku Please mark me as a BRAINLIEST |
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| 26. |
Difference between elements and compounds in very short answer |
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Answer» Ur ANSWER is here ⤵ 1.ᴀɴ ᴇʟᴇᴍᴇɴᴛ ɪꜱ ᴀ ꜱᴜʙꜱᴛᴀɴᴄᴇ ᴍᴀᴅᴇ ᴏꜰ ꜱᴀᴍᴇ ᴛyᴩᴇ ᴏꜰ ᴀᴛᴏᴍꜱ, ᴡʜᴇʀᴇᴀꜱ ᴀᴄᴏᴍᴩᴏᴜɴᴅ ɪꜱ ᴍᴀᴅᴇ ᴏꜰ ᴅɪꜰꜰᴇʀᴇɴᴛᴇʟᴇᴍᴇɴᴛꜱ ɪɴ ᴅᴇꜰɪɴɪᴛᴇ ᴩʀᴏᴩᴏʀᴛɪᴏɴꜱ. 2.ᴇxᴀᴍᴩʟᴇꜱ ᴏꜰ ᴇʟᴇᴍᴇɴᴛꜱ ɪɴᴄʟᴜᴅᴇ ɪʀᴏɴ, ᴄᴏᴩᴩᴇʀ, ʜyᴅʀᴏɢᴇɴ ᴀɴᴅ ᴏxyɢᴇɴ. ᴇxᴀᴍᴩʟᴇꜱ ᴏꜰ ᴄᴏᴍᴩᴏᴜɴᴅꜱ ɪɴᴄʟᴜᴅᴇ ᴡᴀᴛᴇʀ (ʜ2ᴏ) ᴀɴᴅ ꜱᴀʟᴛ (ꜱᴏᴅɪᴜᴍ ᴄʜʟᴏʀɪᴅᴇ - ɴᴀᴄʟ). |
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| 27. |
Which of the following has maximum number of molecule ? |
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Answer» Option (i) 15 L of water at STP has maximum number of molecules. It is because at same temperatture and PRESSURE, LIQUID water has maximum density than EQUAL volume of ice and water vapour. Therefore, 15 L of water will have maximum molecules than 15 L of H2O gas and 15 L of Ice. |
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| 28. |
Example of explosion |
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Answer» Answer: Examples include an overheated boiler or a SIMPLE tin can of beans tossed into a fire. Boiling LIQUID expanding vapor explosions are one type of mechanical explosion that can OCCUR when a vessel CONTAINING a pressurized liquid is ruptured, CAUSING a rapid increase in volume as the liquid evaporates. |
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| 29. |
How can Human resource proved to be an asset for country with the help of the example of Japan |
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Answer» they are IMPROVING the TECHNOLOGY in many WAYS LIKE the pocket AC. |
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| 30. |
What is a radical define |
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Answer» Answer: relating to or AFFECTING the FUNDAMENTAL NATURE of something; far-reaching or thorough. |
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| 31. |
Nettle stings cantain formic acid?what would you rub nettle stong to stop it from hurting |
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Answer» Answer: heya ur answer is : Explanation: To treat a sting from a stinging NETTLE, try not to touch the AFFECTED area so you don't rub the CHEMICALS released by the plant further into your skin. After 10 minutes, wash your skin with soap and warm water or a clean cloth. Alternatively, apply aloe vera or a paste made out of BAKING soda and water. mark it as brainliest PLS ...follow me ♥ |
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| 32. |
Define valency in terms of hydrogen |
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Answer» VALENCY in terms of hydrogen is the number of hydrogen ATOM combine with or replace one atom of ELEMENT |
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| 33. |
All pure substance have |
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Answer» Explanation: The SUBSTANCES that are free from any kind of mixture and contain only ONE kind of particle are pure substances. Examples of pure substances include IRON, aluminum, SILVER, and gold. hope it HELPS ☺ |
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| 34. |
Why rathor ford said that nucleus is spherical in shape |
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Answer» Answer: ATOMS are not spherical in shape. The liquid drop model for a nucleus assumes thenucleus to be spherical, that is approximation made to explain the binding energy of thenucleus and certain other properties like the CRITERIA for nuclear FISSION to occur. |
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| 35. |
Why phosphorous has 5 electron in its valence shell |
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Answer» Answer: It should be 3 because phosphorus has 5 electrons in its valence shell. ... THEREFORE it accepts 3 electrons and completes its OCTET because ACCEPTING 3 electrons would be much EASIER than to donate 5 electrons. Since the valency of phosphorus is 3 but they can expand their valency ,because of the vacent d orbital |
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| 36. |
Which one of which one of the following is employed in making explosives? (A) Methanol (B) Oxalic acid (C) Glycerol(D) Urea |
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| 38. |
All elements are artificial prepared true or false |
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Answer» Answer:FALSE, some ELEMENTS occur in nature while some are PREPARED in the lab Explanation: |
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| 39. |
Explain the factors which affect the evaporation ? |
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Answer» Answer: Temperature: The rate of evaporation increases with an increase in temperature. SURFACE area: The rate of evaporation increases with an increase in surface area. Humidity: The AMOUNT of water VAPOUR PRESENT in the air is called humidity. ... Wind speed: Evaporation increases with an increase in wind speed. |
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| 40. |
Definition of emprical formula |
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Answer» Answer: In chemistry, the empirical formula of a chemical COMPOUND is the simplest positive integer ratio of ATOMS present in a compound. A simple example of this concept is that the empirical formula of SULPHUR monoxide, or SO, WOULD simply be SO, as is the empirical formula of disulphur dioxide, S2O2 |
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| 42. |
What is the mass of 6.022×10*24 molecules of H2SO4 ? |
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Answer» Answer:83g Explanation: |
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| 43. |
What is Stoichiometry |
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Answer» Answer: A Stoichiometry is the relationship between the RELATIVE quantities of substances taking part in a reaction or forming a compound, typically a RATIO of whole integers. Hope It HELPS You. |
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| 44. |
Polymers have(A) Absolute molecular weight(B) Average molecular weight(C) Low molecular weight(D) Absolute melting point |
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| 45. |
Please give IUPAC name of the compound |
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Answer» HOPE it's helpful |
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| 46. |
Anybody can solve this?? |
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Answer» C2HO Ethynyloxy
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| 47. |
The background of how chemistry improves the world? |
Answer» Entire Living KINGDOM is made up of Chemical Combinations, But Some Things are effected by ATMOSPHERE,,For their treatment, We take help of chemistry,,U can take the EXAMPLE, Of "Antibiotics" |
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| 48. |
10 °C पर जल की भौतिक अवस्था क्या होती है? |
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Answer» steam on 100'c water in between them |
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| 50. |
Plan anexperiment to prepare pure,dry crystals of magnesiumsulfate, MgSO4 , by reacting asuitable magnesium compoundwith a suitable acid. You mayuse equations if you wish!!!!(will vote you as most BRAINLIEST answer!!!)THNX! |
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Answer» Explanation: |
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