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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. |
A) Equal masses of zinc (at. mass = 65) and iodine (at. mass = 127) were allowed toreact till completion of reaction to form ZnI2. Which substance is left unreacted and to what fraction of its original mass? |
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| 2. |
What is the formula of hydrated iron oxide (rust) ?Only proper answers allowed, else it will be reported. |
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Answer» Fe2o3.32H2o |
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| 3. |
In the formation of CO2, 12 g of Carbon requires 32 g of O2 to form 44g of CO2.What massof CO2will be formed if 12 g of carbon is reacted with 64 g of O2, give valid reason for your answer.m |
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Answer» Answer: |
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| 4. |
The EA of Be is greater than Mg. This is due toA nueclear chargeB atomic sizeC both a and bD none of theseANSWER CORRECT |
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Answer» Explanation: as Atomic size INCREASES ,Electron affinity decreases |
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| 5. |
A) Elements in the Periodic table show periodicity in properties . List any four such propertiesb) Give reasons for the following :i) No fixed position is assigned to hydrogen in the periodic table .ii)Lithium atom is smaller than sodium atom.iii) Chlorine (atomic Number : 17) is more electronegative than sulphur (Atomic Number : 16) |
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Answer» Answer: a) periodic properties are: atomic radii ionisation potential electron affinity Electronegativity. Explanation: B) i) because it resembles alkali metals by forming positive ions and resembles halogens by forming diatomic molecule. ii) Li has 2 shells and Na has 3 shells. So Li is smaller than Na. iii) CHLORINE has GREATER attraction for ELECTRONS than sulphur. It is more electronegative than sulphur. |
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| 6. |
A sample of water under study wasHoboid at 102 C at normal de temperature andfoundpressure. Is the water pure I will this waterfreenereere at o'c ? Comment. |
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Answer» Answer: Answer: No, the water is not pure. It is because, the BOILING point of pure water is 100°C but the given SAMPLE boils at 102°C. It INDICATES that it has some dissolved impurities. Explanation: |
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| 7. |
17. Calculate the weight of CO having the same number of oxygen atoms as are present in 22 gof CO2 |
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Answer» CALCULATE the weight of carbon monoxide having the same NUMBER of oxygen atoms as are present in 22g of carbon dioxide. Molar mass of CO=12+16=28 G By definitioon, 6.022×1023 atoms (or 1 mole oxygen atoms) are present in CO = 28 g. |
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| 8. |
18. Write the name of two elements which are liquid at room temperature.तत्वों का नाम लिखें जो कमरे के तापमान पर द्रव होती है।(a) Sn and Hg (टीन एवं पारा)(b) Hg and Br (पारा एवं ब्रोमीन)(c) Br and Sn (ब्रोमीन एवं टीन)(d) None of these (इनमें से कोई नहीं) |
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Answer» your answer is b. Hope of it HELPS!! Do RATE it. |
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| 9. |
An element has four neutrons three protons and two electrons find whether if it is a cation, anion or neutral atom |
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Answer» cation Explanation: |
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| 10. |
7.00 g of a gas occupies a volume of 4.1 L at 300 Kand 1 atm pressure. What is the molecular mass ofthe gas? |
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Answer» ✔✔Here is your answer ✔✔ PV= m/M RT. or. M=m×RT/PV =7.0×0.082×300/1×4.1 =42 Explanation: |
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| 11. |
Strong electrolytees 4: What type of a battery is lead storage battery? Write the anode, cathodereactions & overall reaction occurring in a lead storage battery, |
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Answer» iyviyviyvljgvuyviyviypg Explanation: V uyfiugiugo7g97y98ougg7ogpig08g97gouv7yc GOOD 44xyrxcuyf8yf7tc8yf7tct7futf7yf7tct7ct7c7t g8uviycutcutctucug guviyv7t |
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| 12. |
Complete and balance the following reaction : - (5)1. K + H2O ..................+ ..................2. Ca + H2O ..................+ ..................3. Zn + HCl ..................+ ..................4. Zn + NaOH ..................+ ..................5. Fe + H2O ..................+ .................. |
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Answer» Answer: 1. 2K(s) + 2H2O (l) ——> 2KOH (AQ) + H2 (g) 2. Ca(s) + 2H2O (l) ——> Ca(OH)2 (aq) + H2(g) 3. Zn(s) +2HCl (aq) ——> ZnCl2 (aq) + H2 (g) 4. Zn (s) + 2NaOH(aq) ——> Na2ZnO2 (aq) + H2(g) 5. 3Fe(s) + 4H2O (l) ——> FE3O4(s) + 4H2(g) the REACTION is balanced now.... hope it helps you.. |
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| 13. |
A string of lamps of 0.4 and mass of 0.16 grams if the tension in the string is 70 N. What are the 3 lowest frequncies |
Answer» I hope you have GOT your answer so MARK me brilliansit and FOLLOW me ❣️ |
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| 14. |
In a reaction, 3A →Products, the concentration of A decreases from 0.5Mol/ L to 0.4 mol / L in 10 minutes. Calculate the rate during this interval |
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| 15. |
Salt whose solubility increases as well as decreases with increase in temperaturePotassium sulphatePotassium chloridePotassium nitrateCalcium sulphate |
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Answer» Answer: Heyyyy,Here is your answer DEAR and thiss time I am sure for the answerAnswer is POTASSIUM chlorideHope it helps UPlz thank me and mark me as brainliest...... |
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| 16. |
A weak magnet Y is placed near a strong magnet X as shown in the figure. How will the magnets move?please answer ASAP |
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Answer» By ATTRACTION Explanation: |
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| 17. |
Rubber is soluble inAcetoneCarbondisulphideEthanolOxalic acid |
Answer» I GUESS the answer is ACETONEbut I am not SURE...... |
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| 18. |
ਸਿੱਖ ਰੈਜ਼ੀਮੈਂਟ ਦੀ ਅਗਵਾਈ ਕੌਣ ਕਰ ਰਿਹਾ ਸੀ? * (ੳ) ਅੰਗਰੇਜ਼ ਅਫ਼ਸਰ(ਅ) ਈਸ਼ਰ ਸਿੰਘ(ੲ) ਇੱਕ ਨਾਇਕ(ਸ) ਇੱਕ ਲਾਂਸ ਨਾਇਕ । |
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Answer» Answer: A) part is correct for your QUESTION . Explanation: HI FREINDS , I'M SAGAR JALVI . PLZ FOLLOW me guys . see my profile and then FOLLOW me . plz guys . I ALWAYS GAVE YOUR ANSWER IN A PROFESSIONALLY WAY . SO FOLLOW ME AND ALWAYS GET ANSWER FROM ME . ☺ |
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| 19. |
A flask containing some He gas at 1.5 atmand 300 K is connected to another flask, fourtimes larger in volume containing nitrogengas at same temperature and pressure bymeans of a narrow tube of negligible volume.The bigger flask was then kept in a thermostatbath maintained at 500 K, while other flaskwas maintained at constant 300 K. Determinethe final pressure. |
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Answer» ...... ............... |
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| 20. |
II. Multiple Choice Questions (Type-116. One mole of oxygen gas at STP is equal to(a) 6.022 x 1023 molecules of oxygen(6) 6.022 x 1023 atoms of oxygen(c) 16 g of oxygen(d) 32 g of oxygenodi |
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Answer» Answer: 6.022*1023 molecule of o2(avogadro no.) Explanation: =32G of o2 . hence one molecule of OXYGEN gas is EQUAL to MOLECULAR WEIGHT of o2 and avogadro no. |
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| 21. |
Identify the reaction order from the following rate constant, k=2.3 x 10-5L mol-1S-1 |
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Answer» Answer: Explanation:(Hint: dilution OCCURS) Ksp(Na3PO4) = 1.3 x 10-20 a) AgCl 8.7 x 10 -7 M b) AG3PO4 2.3 x 10 -7 M c) AgCl 1.4 x 10 -8 M d) Ag3PO4 7.2 x 10 -8 M |
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| 22. |
. The atomic theory of matter was proposed by: *(a) Chadwick(b) Lavoisier(c) Proust(d) John Dalton |
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Answer» Answer: d) John Dalton is the RIGHT answer |
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| 23. |
If the sum of two numbers is 42 and their product is 437,then find the absolute difference between the numbers. |
Answer» ANSWER:FIRST STEP is to DIVIDE the NUMBER 437÷42then the answer is 10.40 |
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| 24. |
The density of a metal is calculated to 8.9377 g/cm3, using weight and volume measurements.The ± absolute error is determined to be ± 0.006 g/cm3.The ± relative error for the above density determination is: |
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Answer» HII i am not saure you are INTELLIGENT |
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| 25. |
K State whether the following statements is True or False1. The globe is a flat representation of the earth.2. 061 N latitude is also known as the Arctic circleTemperate zone is the hottest place of the earth4 USA has 5 time zones& The Greenwich Meridian is the 0° longitude |
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Answer» HEYY,
hope it hepls you. |
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| 26. |
Represent the galvanic cell in which the reaction,Zn(s) + Cu2+ (aq) -----→ Zn2+(aq) + Cu (s) takes place. |
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Answer» Answer: The galvanic cell in which the given reaction takes PLACE is depicted as: (i) Zn electrode (anode) is negatively charged.
(ii) Ions are carriers of CURRENT in the cell and in the external circuit, current will flow from silver to ZINC.
(iii) The reaction taking place at the anode is given by, Zn(s) → ZN2+(aq) + 2e- The reaction taking place at the cathode is given by, AG+(aq) + e- → Ag(s) |
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| 27. |
1 State one example each characterised bythe following alongwith the chemicalequation:() Change in state (ii) Evolution of gas(iii) Change in temperature CBSE 2016 |
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Answer» Answer: 1) ice melting to WATER 2)water EVAPORATES from rivers 3)MILK is heated up and boiled |
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| 28. |
Current of 2.6 ampere is passed through CuSO4 solution for 6 minutes 20 seconds. Theamount of Cu deposited is (At. wt. of Cu = 63.5, Faraday = 96500 C) |
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Answer» Answer: SH ddj DHX xuc CUD zu Duc cud xi cjx xhx sjd jz XIZ zhdbxv. c Explanation: jz zjx sis sudbxi |
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| 29. |
Ques 1: Calculate the molarity of a sulphuric acid solution in which the molefraction of water is 0.85. |
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Answer» mol FRACTION of WATER in SOLUTION = 0.85 So mol of ACID = 1-0.85 = 0.15 Now m= nw×molecularwtofwater 1000×molofacid m= 0.85×18 1000×0.15 =9.8mol/kg |
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| 30. |
In the formation of ammonia molecule , nitrogen attains the stable electronic configuration ofa) Heliumb) Neonc) Argon |
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Answer» Answer: |
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| 31. |
Q. What is the decreasing order of reactivitySN2 reaction ?—1 - Bromo - 2,2-dimethypropane1- Bromopentane1-Bromo-2-methylbutane |
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Answer» Answer: 1 - Bromo-2-dimenthypropane 1 - bromopentane 1 - bromo-2-methylbutane Explanation: the SN2 REACTIONS are sensitive to steric HINDRANCE. greater the steric hindrance TOT he attacking nucleophile, lesser will be reactivity. |
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| 32. |
प्र.4) निम्नलिखित में से कौन सा शब्द संज्ञा शब्दहैख) तेरहग) उनकाघ) सभी विकल्प सही है |
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Answer» तेरह शब्द संज्ञा है। उनका शब्द सर्वनाम है। |
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| 33. |
I. The boiling points of hydrides of group 16 are in the ordera) H2O > H2Te > H2S > H2Se b) H2O > H2S > H2Se > H2Hec) H2O > H2Te > H2Se > H2S d) None of theseii. Affinity for hydrogen decreases in the group from fluorine to iodine. What of the halogen acids should have highest bond dissociation enthalpy? a) HF b) HCl c) H Br d) HIiii. If cone, of reactant 'A' is increased 10 times and rate of reaction becomes 100 times. What is order to 'A'?a) 1 b) 2 c) 3 d) 4iv. The half life period of first order reaction is 1386 seconds. The specific rate constant of the reactions is.a) 0.5x10-2s-1 b) 0.5x10-3s-1 c) 5.0x10-2s-1 d) 5.0x10-3s-1v. The change required for the reductions of 1 mol of MnO2-to MnO2 is a) 1 F b) 3 F c) 5 F d) 6 Fvi. Which of the following statement is correct? a) E cell and of cell reaction both are extensive properties.b) E cell and of cell reaction both are intensive propertiesc) E cell is an intensive property while of cell reaction is an extensive property.d) E cell is an extensive property while of cell reaction is an intensive property. |
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Answer» H2O ought to have the lowest BOILING point but it doesn't because of hydrogen BONDING. Hydrogen Sulfide is -76*C. and is the minimum. Warmer still is Hydrogen SELENIDE with -41*c. |
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| 34. |
12. Electrolysis of molten NaCl is done.A. Write the chemical equation of the reaction taking place at the Cathode ? |
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| 35. |
1. Barium chloride on reacting with ammonium sulphate forms bariumsulphate and ammonium chloride. Which of the following represents the type ofreaction involvedi. Displacementii Precipitationiii. Combinationiv. Double displacementb. iva. i and iionlyc. ii and ivd. i only |
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Answer» pls pls MARK as brainliest |
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| 36. |
Write the name and molecular formula of an organiccompound having its name suffixed with-ol' andhaving two carbon atoms in the molecule. With thehelp of a balanced chemical equation indicate whathappens when it is heated with excess of conc.H.SO, |
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Answer» Answer: compound is ethanol Explanation: when excess of alcohol is heated with conc. sulphuric acid at 140°C, it forms DIETHYL ether on account of PARTIAL dehydration. 2C2H5OH---conc.H2SO4(ecxess)--->C2H5-O-C2H5+H2O When excess of conc. sulphuric acid is heated with ETHYL alcohol at 170°C, the alcohol is dehydrated to ETHYLENE gas. C2H5OH----conc.H2SO4(excess)----->C2H4+H2O |
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| 37. |
NH3 gas can be prepared by Haber's process as, N2(g) + 3H2(g) →2NH3(g). At a particular moment concentration of all the species is2 moles; calculate the concentration of N2 and H2 taken initially. |
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Answer» ok Yes, you've pretty much reached Genius status when you've been answering and helping your Brainly peers for a long time, posting thoughtful, high quality answers. You know your way AROUND Brainly like the back of your hand and others trust you for your insightful and extremely helpful solutions to their questions. You TRULY are the best of the best, an exemplary Brainly user and have reached the pinnacle of your Brainly career. Keep up the good work! danielstevegabby danielstevegabby Rank: Expert 2613/3000 20/15 Your influence 1 Answering Streak Your Streak is on! Answer another question tomorrow and keep it going. Fun fact An apple, potato, and onion all taste the same if you eat them with your nose plugged 1 2 2 Get +4 bonus 2 Last 7 days Overall Your stats from the last 7 days compared with the previous 7 days Popularity 102 People learning from your answers. +3% Brainliest 4 This MANY users said your answers were the best! Thanks 13 Your effort is appreciated! +18% Questions answered 29 +20% 16 Sep - 22 Sep 1 Wed 1 Thu 14 Fri 4 Sat 9 Sun 0 Mon 0 Tue English 12 Math 4 Biology 4 Geography 4 Social Sciences 3 Physics 1 Chemistry 1 Show More My challenges Answer 10 questions from any subject in 48 hours to collect 100 points 9/10 9h : 07m Answer 25 questions from any subject in 48 hours to collect 400 points 5/25 TRY IT AGAIN! You may attempt only ONE challenge at a time. Answer 5 questions from any subject in 48 hours to collect 50 points 5/5 Done TRY IT AGAIN! You may attempt only one challenge at a time. Challenges to complete Answer 5 Science questions in 48 hours to collect 50 points 0/5 2d : 00h START You may attempt only one challenge at a time. Answer 10 Science questions in 48 hours to collect 100 points 0/10 2d : 00h START You may attempt only one challenge at a time. Explanation: |
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| 38. |
Calculate the average atomic mass of Mg using the followinf data% NaturalAbudance.&. Molar mass24Mg. 80. 2425Mg. 10. 2526Mg. 10. 25 |
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Answer» Change each percent ABUNDANCE into DECIMAL form by dividing by 100. Multiply this value by the ATOMIC mass of that isotope. Add together for each isotope to GET the average atomic mass. |
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| 39. |
Write the chemical symbols of two elements which have got their name from the names of theelements in Latin. |
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| 40. |
Among the following species, identify the isostructural pairs: NF₃, NO₃⁻, BF₃, H₃O⁺, HN₃options are1-[NF₃, NO₃⁻] and [BF₃, H₃O⁺]2-[NF₃, HN₃] and [NO₃⁻, BF₃]3-[NF₃, H₃O⁺] and [NO₃⁻, BF₃]4-[NF₃, H₃O⁺] and [HN₃, BF₃] |
Answer» SOLUTION:-Isostructural species are those which are in geometry as WELL as HYBRIDIZATION (a) NF 3 Number of lone pairs = 1 No of bond pairs = 3 Hybridization = sp 3 Geometry = Tetrahedral ( Trigonal pyramidal) (b) NO 3- Number of lone pairs = 0 No of bond pairs = 3 ( only SIGMA bonds must be counted ) Hybridization = sp 2 Geometry = Trigonal planar (c) B F 3 Number of lone pairs = 0 No of bond pairs = 3 Hybridization = sp 2 Geometry = Trigonal planar (d ) H 3 O + Number of lone pairs = 1 No of bond pairs = 3 Hybridization = sp 3 Geometry = Tetrahedral ( Trigonal pyramidal)
( e ) HN3 The CENTRAL N atom is sp hybridised and the other two are sp 2 hybridised Hybridization = sp Geometry = linear Refer the attachment for its structure Answer:-3 -[NF₃, H₃O⁺] and [NO₃⁻, BF₃]
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| 41. |
On adding dilute "Copper Oxide"a blue-green coloured solution is formed.i) What is the "blue -green" colour of the solution due to? ii) Write the chemical equation involved in the reaction . iii) Why is " Copper Oxide" considered as a " base"? |
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Answer» please follow me please |
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| 42. |
Foam the given data set determine anguladispersionby the prism and dispesivepo co or ofits material foo extreme colocos& URE 1062 , rev=1066SR=103 |
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Answer» jfjjffjfjfkfkdkdkdkdkdkiririfkfkfjxjxjcjcfg f ffkfkfkfg g gf f f g h yy syoee9epe e r ofdd ed doodled drrpdpd d d dFoam the GIVEN data set determine angula dispersion by the prism and dispesive po co or of its material FOO EXTREME colocos & URE 1062 , rev=1066 SR=103 d ddppddp |
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| 43. |
Which among these have highest gain enthalpy1- hydrogen2-sodium 3-oxygen4- neon |
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| 44. |
100 cm3 of a gas at 27 degree Celcius is cooled to 20 degree Celcius at constant pressure.Calculate the volume of gas at 20Celcius. |
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Answer» Answer: V1 = 80ml P1 = 100cm V2 =160ml P2 = 740 mm P1V1 = P2V2 P2 = P1V1/V2 = 100 x 80 = 50 CM of Hg 160 Explanation: please mark as brilliantist |
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| 45. |
A Current of s Amperes is passed throughacidifled water for 30 min then calculate thesette weight of H2O, deposited at catrode andanode and volume of o2 plz answer this |
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Answer» Answer: A current of 0.5 ampere is PASSED through acidulated water for 30 MINUTES CALCULATE weight of o2 evolved. 2. See ANSWERS. Log in to ... Explanation:At Anode: 4OH- =2H2O +O2 +4e-. 4*96500 C releases O2 =32gram. then,. 1C release 32/4*96500 ... What is the volume NEEDED to make 2. 5l of 0.25M mark me as brainliest.... |
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| 46. |
Write the principle of the following refining methods :(a) vapour phase refining(b) chromatography |
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Answer» (i) The METAL should FORM a volvatile compound with an available reagent. (ii) The volatile compound should be easily decomposable, so that the metal can be easily recovered. This METHOD is used for refining nickel, zirconium and TITANIUM. |
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| 47. |
Soil?10. How has the Green Revolution in some areas resulted in short-term gains butlong-term losses to farmers? |
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Answer» Explanation: The Green Revolution has resulted in short terms gains but it has become long term LOSSES to FARMERS in some AREAS. The excessive USE of fertilizers and pesticides made the crops to grow artificially. The natural taste of the crops SPOILED due to the use of chemicals. ... The water reserves are also effected by Chemicals. i hope this was helpfull for u |
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| 48. |
The molecular mass of Water is 18.a. Find the mass of 1 GMM H2O.b. How many moles are there in 180g of H2O |
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Answer» Answer: 10 mol hoge follow me |
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| 49. |
3. Which of the following is not a chemical change ?a. Ripening of fruits.b. electrolysis of waterc. Dissolution of common salt in waterd. Heating of copper wire in presence of air at high temp. |
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Answer» Answer: Heating of COPPER wire in presence of AIR at high temp. Follow me and LIKE Karna mat bhul na Aur 5star rateing dena |
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| 50. |
For the reactionA + 2B = products :The rate law is given asproductsR = k [A][B]²From the foll data, calc value of xand ySNO[A] (M)[B] (M)t½ (min)2losox4.102.100438y ч410 |
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Answer» Answer: A+2B→ products is : RATE =K[A][B]2 Rate of the reaction at 30∘ C is FOUND to be 0.125 M/s , when [A]=2.0 M and [B]=0.4 M . |
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