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. |
Explain what happen when iron metal is left exposed in moist weatherNcert chemistry (science) class 10 chapter 1 |
|
Answer» Explanation: When iron is left in MOIST air, it forms an oxide layer called rust. It is a reddish- BROWN flake WHUCH gets coated over iron article. The reaction that takes place is FE2O3. |
|
| 2. |
During de-excitation of electrons say from the 5th orbit to 1st orbit, does it enter the orbits in between? plz help... |
|
Answer» Answer: Yes. It GOES step by step to the 4th then 3rd then 2ND then 1ST by LOSING energy Explanation: |
|
| 4. |
Calculate the percentage of each element in the compound MgSO4 |
Answer» ANSWER:We have given compound MgSO₄ : Molar mass of MgSO₄ = ( 24 + 32 + 64 ) = 120 g / mol. a). % composition of MG in MgSO₄ : = > ( 24 / 120 ) × 100 % = > ( 1 / 5 ) × 100 % = > 20 % B). % composition of S in MgSO₄ : = > ( 32 / 120 ) × 100 % = > 0.2666 × 100 % = > 26.67 % c). % composition of O in MgSO₄ : = > ( 64 / 120 ) × 100 % = > 0.5333 × 100 % = > 53.33 % Hence we get required answer. |
|
| 6. |
A current of 1.50 amp was passed through an electrolytic cell containing AgNO3 solution with inert electrodes. The weight of Ag deposited was 1.50g. How long did the current flow? (2marks)(b) Write the reactions taking place at the anode and cathode in the above cell. |
|
Answer» user_photo Type your question... 12th Chemistry Electrochemistry Electrolytic Cells and Electrolysis Three electrolytic cells A,... CHEMISTRY Three electrolytic cells A,B,C containing solutions of ZnSO 4
,AgNO 3
and CuSO 4
, respectively are connected in SERIES. A steady current of 1.5 amperes was passed through them until 1.45 g of silver deposited at the cathode of cell B. How LONG did the current flow? What mass of copper and zinc were deposited? November 22, 2019avatar Puneetha Adak SHARE VIDEO EXPLANATION ANSWER Cell B: Ag + +e − ⇌Ag at cathode. 1 mole (108 g) of Ag is deposited by 96500 C. 1.45 g of Ag will be deposited by 108 96500×1.45
=1295.6C. Q=It 1295.6=1.5×t t=864s Cell A: Zn 2+ +2E − →Zn 2 moles of electrons (2×96500 C of current) produces 1 mole (63.5 g) of zinc. 1295.6 C of electricity will deposit 2×96500 65.3
×1295.6=0.438 g of zinc Cell C: CU 2+ +2e − →Cu 2 moles of electrons (2×96500 C) of current will produce 1 mole (63.5 g) of Cu. 1295.6 C of current will deposit 2×96500 63.5×1295.6
=0.426g of copper |
|
| 7. |
Predict the type of each reaction(a) 2ag+S---Ag2S.(b) NH4NO2---N2+2H2O. (C) 2NAI+Cl2---2NaCl+l2. (d) CuCl2+2NaOH---Cu(OH)2+2NaClNcert chemistry (science) class 10 chapter 1 |
|
Answer» Answer: 1-combination REACTION 2-Decomposition reaction 3-Single DISPLACEMENT reaction 4-Double displacement reaction |
|
| 8. |
What is adulteration process |
|
Answer» Answer: Incidental contamination during the period of GROWTH, harvesting, storage, PROCESSING, transport and DISTRIBUTION of foods are also considered. ... Food is declared ADULTERATED if: A substance is added which DEPRECIATES or injuriously affects it. Cheaper or inferior substances are substituted wholly or in part |
|
| 9. |
Elements with high electro negativity are.A. Soft solidsB. Hard solidsC. Good reductantsD. Good oxidants |
|
Answer» Answer: Of the main GROUP elements, FLUORINE has the highest ELECTRONEGATIVITY (EN = 4.0) and cesium the lowest (EN = 0.79). This indicates that fluorine has a high tendency to gain ELECTRONS from other elements with lower ELECTRONEGATIVITIES. |
|
| 10. |
Balance the following chemical equations.a. H2SO4 + NaOH — Na2SO4 + H20b. NaCl + AgNO3 ->AgCI + NaNO3C. CH4 + O2 CO2 + H20d. HNO3 + Ca (OH)2 Ca(NO3)2 + H2Oe. BaCl2 + H2SO4 BaSO4 + HCIf. BaCl2 +K2SO4 Baso, + KCIg. C₂H₂ + O₂ CO2 + H2O |
|
Answer»
|
|
| 11. |
Explain an. activity to show how acid reacts with carbonates |
|
Answer» The activity discriving the reaction of acid with metal carbonates and metal hydrogen carbonate:- 1. Take a SMALL amount of metal carbonate in test tube A and metal bi-carbonate in test tube B. 2. Pour few drops of sulphuric acid in both the test tubes. you will notice evoltion of colourless gas. 3. Pass the evolved gas in both test tube through the lime water eith the help of delivery tube. 4. You will notice that the lime water turn colorless in both the cases. This indicates that the evolved gas carbon-di-oxide. Example:- ZnCO3 + H2SO4 → ZNSO4 + CO2 + H2O Explanation: |
|
| 12. |
Explain working principle of turbidity meter. |
|
Answer» Answer: Turbidity Analyzer Working Principle. Turbidity is an OPTICAL PROPERTY of water based on the amount of light scattered and absorped by collodial and suspended particles. ... The light transmitted from the source is directed in equal STRENGTH to the REFERENCE DETECTOR and into the medium Explanation: hope it will help you |
|
| 13. |
on adding dilute hydrochloric to copper oxide powder the solution formed is blue green. Predict the new compound formed which gives the colour. write a balanced Chemical equation this reaction. |
|
Answer» Answer: HI buddy Explanation: the blue-green SOLUTION is copper chloride hope it HELPS you |
|
| 14. |
On dilution pH is a solution |
|
Answer» <STRONG>Explanation: xbxjeuu hu Hence, the growth of nationalism in the colonies is linked to an anti-colonial movement. ... In the process of their struggle with colonialism PEOPLE began discovering their unity. Anti-colonial movement GAVE a strong ISSUE to the people with which they could identify and could come on a common platform.Mar 5,bhfidjheueieiirirreif |
|
| 15. |
Detectors in FTIRName it |
|
Answer» Explanation: Three TYPES - Pyro electric detector - pyro conducting DETECTER - thermal detecter |
|
| 16. |
M(co)3 in paii and sigma number |
|
Answer» The sigma bond is FORMED by the head-on OVERLAP of two sp orbitals. The pi bonds are formed by the side-on overlap of 2p orbitals. where, X = NUMBER of carbon atoms; Y = number of hydrogen atoms and P = number of π bonds/double bonds. Hope you LIKE it my Ans And plz mark as me [email protected]❤ |
|
| 17. |
Find out the odd one Ca2+,Cl-K+,S- |
|
Answer» Answer: CA2+ IS THE ODD ONE OUT AS IT HAS VALENCY OF 2 WHEREAS OTHERS HAVE VALENCY OF 1 <<FOLLOW>> MARK IT AS THE BRAINLIEST |
|
| 18. |
(Q) Calculate the amount of work done when a gas expands (I) isothermally and reversibly from volume v1 and V2.(ii) isothermally and irreversibly from volume v1 to v2 .From these,show that the work done ia a reversible process is greater than that in an irreversible process. |
|
Answer» bdhdi Hence, the growth of nationalism in the colonies is LINKED to an anti-colonial movement. ... In the process of their STRUGGLE with colonialism PEOPLE began discovering their unity. Anti-colonial movement gave a strong issue to the people with which they COULD identify and could come on a common platform.Mar 5,hsuhsusueueueu |
|
| 19. |
Answer to this reaction |
|
Answer» Displacement REACTION is the answer Explanation: Hope it helped you mark as BRAINLIEST and follow me. |
|
| 20. |
______ a detailed weatherforcast. |
|
Answer» SORRY I can't UNDERSTAND |
|
| 22. |
Why buffer needed????? |
|
Answer» A buffer is a solution that can resist pH change upon the addition of an ACIDIC or basic components. It is able to neutralize small amounts of added acid or base, thus maintaining the pH of the solution relatively STABLE. This is important for processes and/or reactions which REQUIRE specific and stable pH ranges. Explanation: hope it will help you |
|
| 23. |
What is saponification reaction |
|
Answer» Saponification is a process by which triglycerides are reacted with sodium or potassium hydroxide (lye) to PRODUCE glycerol and a fatty ACID salt called "SOAP." The triglycerides are most often animal fats or vegetable oils. When sodium hydroxide is USED, a hard soap is produced. Hope it's helpful for u GUYS |
|
| 24. |
1.11 gm of CaCl2 is mixed with 1.42 gm of Na2So in 1 lit water in Round bottom flask then products obtained in reaction are (Chemical equation Na2So4 + CaCl2- Caso4 + 2Nacl) |
|
Answer» CALCIUM sulphide &&. SODIUM chloride.... Mark me as brainlist ✌️♥️✌️♥️ |
|
| 25. |
What do you observed when zinc oxide heated and then cooled |
|
Answer» Answer: When Zinc carbonate is heated which is a white POWDERY solid, gives carbon DIOXIDE and a yellow solid of zinc oxide. As it forms different PRODUCTS, it UNDERGOES chemical changes. On cooling yellow solid turns in to white, which is a physical change. The PROCESS involves both physical and chemical change. Explanation: MARK ME THE BRAINLIEST...... |
|
| 26. |
What do you mean by molecular mass of an molecule |
|
Answer» Molecular MASS is a NUMBER equal to the sum of the ATOMIC masses of the atoms in a molecule. The molecular mass gives the mass of a molecule relative to that of the 12C ATOM, which is taken to have a mass of 12. |
|
| 27. |
Difference Between Material and Substance... ;-) |
|
Answer» The material is a Something that has Certain Characteristics which are used to MANUFACTURE or to produce the desired product. For example, WATER and Fibres are examples of Material. 2. SUBSTANCE: A Substance is a matter that has a definite STRUCTURE or composition. |
|
| 28. |
Name two Indian breeds of sheep ? |
|
Answer» Answer:
Explanation: |
|
| 29. |
Oxidation number of HCl where CL is underlined |
|
Answer» kindly write the complete QUESTIONS or post the picture of that. I can tell you about oxidation Oxidation involves addition of oxygen to a substance , removal of hydrogen from a substance and LOSS of electrons from an atom or an ION. |
|
| 30. |
Number of secondary alkyl halides possible for Ch3H11Cl are |
|
Answer» Answer: Secondary ALKYL halide (2o alkyl halide; secondary haloalkane; 2o haloalkane): An alkyl halide (haloalkane) in which the halogen atom (F, Cl, BR, or I) is bonded to a secondary carbon. General secondary alkyl halide structure. X = any atom but carbon; USUALLY hydrogen. Brainlest plz |
|
| 31. |
Draw a schematic diagram showing interconversion of states of matter and explain each processes.plzz answer fastly as it is quite urgent!!plzzzzzzz answer fastly plzzzzzzzzzzzzzzzzz |
|
Answer» SEE in the ATTACHMENT MATE |
|
| 32. |
Discuss why dissolving of salt in water is a physical change? |
|
Answer» Dissolving a solid in LIQUID, such as table salt in water, is a PHYSICAL change because only the state of the matter has changed. Physical changes can often be reversed. ALLOWING the water to evaporate will return the salt to a solid state. ... It has not combined with the water to cause a chemical reaction. Explanation: Mark as brainliest |
|
| 33. |
EREHEInstructions:Select the UNE correct answer from the given options.For XY2(8) = XY() + Y(g) initial pressure of XY, is 800mm and equilibrium pressure is 960mm. Degreeof dissociation of XY2(g) is:(0.15ESTE,FREELELEmmTWEET(2) 0.4CELESTE HEEFTBEELLELELETELETHEFELLChemiLEHTELEHALEH(3)0.2LEEEEEEEEEEEEtilFEmILL(4) 0.8EEF |
|
Answer» <P> Final Answer : K_p = 100 MM HG Steps: 1) We have, Since, Volume is constant . XY_2(g) \rightarrow XY(g) + Y(g) \\ \\ \\t=0 => 600. \rightarrow 0 \quad + 0 \\ \\ t=t_{eq. } => 600-x \rightarrow x.\quad + x 2) Then at Equilibrium P_T = P_{XY_2}+ P_{XY} + P_Y \\ \\ => P_T = (600-x) + x + x \\ \\ => 800 = 600+ x \\ \\ => x = 200 mm \:Hg 3) Now, K_p = \frac{x*x}{(600-x) } \\ \\ K_p = \frac{200*200}{400} = 100 mm\: Hg Hence, Value of K_p = 100 \: mm Hg
|
|
| 34. |
Which among of the following changes are exothermic or endothermic in nature? A) Decomposition of ferrous suphate. B) Dilution of sulphuric acid. C) Dissolution of sodium hydroxide in water. D) Dissolution of ammonium chloride in water. |
|
Answer» see Explanation: a )ENDOTHERMIC B)EXOTHERMIC C)exothermic d)endothermic |
|
| 35. |
4. Column - I Column - II1) Two bond pairs on central atom P) Bond angle is 109° 28|2) Four bond pairs on central atom Q) Bond angle is 180°R) Bond angle is 120° |
|
Answer» Answer: 1) goes with R and 2)goes with P Explanation: When a compound has two bond pairs, it's central atom MAKES 180 DEGREE with it's neighbour atoms and forms STRAIGHT line and in the second CASE it forms a tetrahedral bond like in ch4. Thank You. |
|
| 36. |
State the characteristic of gas used in supplying oxygen cylinders to hospitals. |
|
Answer» Answer: The gas which is USED in OXYGEN supplying oxygen cylinders to hospitals are HIGHLY COMPRESSIBLE liquids or solids .Therefore the character of the gas is compressibility. mark as BRAINLIST please |
|
| 37. |
UITVUE UITWEI Hom we given optionsOzonolysis of 2, 3-dimethyl -1- butene followed by reduction with zinc and water gives:Methanoic acid and 3-methyl-2-butanone(2) Methanal and 2-methyl-3-butanone(3) Methanal and 3-methyl-2-butanone(4) Methanoic acid and 2-methyl - 3-butanone01 02 0304) |
|
Answer» aarhus aaron aaronic aau ab abac abaca aback abacterial abactinal abacus abacuses |
|
| 38. |
Convert the following temperature into degree celsius : a.565k b. 125k c. 300kplzz answer fastly ...its quite urgent!! |
|
Answer» a. 565 K = (565-273)°C = 292°C b. 125 K = (125-273)°C = -148°C c. 300 K = (300-273)°C = 27°C |
|
| 39. |
Which set of the following moleculeshas only one lone pair of electrons ontheir respective central atoms ?(a) So, (b) XeF, (c) PbCl, (d) SF,(e) CIF,(1) a, c d (2) b, c, d(3) a, b, e (4) a,c, e.......i want the answer in detail about lone pairs!! |
|
Answer» fjjfjfnfrnfnfnfjfjfjbfnfjcincmckfofofifi |
|
| 40. |
calculate the amount of KCL which must be dissolved in 1 kg of water so that freezing point is depressed by 2K kf=1.86k kg/mole |
|
Answer» ASSUMING 100% DISSOCIATION of KCL, |
|
| 41. |
find the freezing point of a solution containing 0.520 gram of glucose dissolved in 80.2 gram of water Kf is equals to 1.86 kg/mole |
|
Answer» C6H12O6=72+12+96C6H12O6=72+12+96 ⇒180gmol−1⇒180gmol−1 ΔTf=Kf×WB×1000MB×WAΔTf=Kf×WB×1000MB×WA ⇒1.86×0.520×1000180×80.20⇒1.86×0.520×1000180×80.20 ⇒0.067 Brainlest PLZ |
|
| 42. |
If the radius of electron orbit in theexcited state of hydrogen atom is476.1 pm, the energy of electron inthat excited state in J is(Radius and energy of electron in thefirst orbit of hydrogen atom are52.9 pm and -2.18 X 10-1 J respec-tively)(1) - 2.42 x 10-18(2) - 19.62 x 10-18(3) - 2.42 x 100(4) - 6.05 x 10-19 |
|
Answer» Answer: Chapter 1 "Introduction to Chemistry" through Chapter 5 "Energy Changes in CHEMICAL Reactions" introduced you to a wide variety of chemical substances and some of the most FUNDAMENTAL CONCEPTS in chemistry, including general descriptions of chemical bonding, mass relationships in chemical equations, and the energy changes associated with chemical reactions. You learned that the atoms of each element contain a unique number of positively charged protons in the nucleus and that a NEUTRAL atom has the same number of ELECTRONS as protons. You also learned that protons and neutrons constitute most of the mass of the atom and that electrons occupy most of the volume of an atom. These facts do not, however, explain the stoichiometries and the structures of chemical compounds; a deeper understanding of the electronic structure of atoms is required. |
|
| 43. |
What is the process of making carbon dioxide |
|
Answer» Carbon dioxide is PRODUCED during the PROCESSES of decay of organic materials and the fermentation of sugars in bread, BEER and wine making. It is produced by combustion of wood and other organic materials and FOSSIL FUELS such as coal, peat, petroleum and natural gas. |
|
| 44. |
A photon of wavelength 4 x 10-7 m strikes a metal surface. Work function of the metal is 2.13 eV. Calculatethe velocity of photoelectrons in ms-1. |
|
Answer» REFER ATTACHMENT for EXPLANATION!! |
|
| 45. |
What so you observe when concentrated sulphuric acid is added to sugar |
|
Answer» Answer: Concentrated SULPHURIC acid is a strong dehydrating agent and PULLS the sugar molecule apart leaving just BLACK carbon which froths due to the heat and water produced. |
|
| 46. |
Calculate the molecular mass of ammonium chloroplatinate |
|
Answer» atomic mass of..... N = 14, H = 1, Cl = 35.5, PT = 195 2(14+1(4)) +195+35.5(6) = 36 + 195 + 213 = 444 |
|
| 47. |
How do you change the state with the help of pressure |
Answer» By GIVING PRESSURE for any WORK.. |
|
| 48. |
Mathmetical derivation of kinetic theory of gases were given by. |
|
Answer» Answer: HI here is your answer Explanation: |
|
| 49. |
calculate the mass of ascorbic acid C686O6 to be dissolved in 75 gram of Acetic Acid to lower its melting point by 1.5 degree Celsius KF is equal to 3.9 kg per mole |
|
Answer» Answer:
|
|
| 50. |
Early Hanuman became food producers during the ............ stone age |
|
Answer» neolithic stone age Explanation: because man FOUND different WAYS of cropping and AGRICULTURE |
|