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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.
| 3. |
What can you say about the nature of oxide on going down a group? give reason |
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Answer» oxide that gives a BASE in water is known as a basic oxide. An amphoteric SOLUTION is a substance that can CHEMICALLY react as either ACID |
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| 5. |
80g salt of weak base and strong acid XY ('d' of solid XY is 2g/cc) is dissolved inwater and forms 2 L of aqueous solution. If'XY' forms CSCI type crystal havingrX+=1.6A°, rY-= 1.864Aº then pH of the resultant solution at 298k is [kB of XOH = 4x10^-5]Options:1) 2 2) 3 3) 4 4) 5 |
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Answer» ong>Answer: 80g salt of weak base and strong ACID 'XY'('d' of SOLID XY is 2g/ CC) is dissolved in water and FORMS 2I. Of aqueous solution. If 'XY' forms CSCL type crustal having rX∘=1.6A∘,rγ-=1.864A∘ then pH of the ... |
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| 6. |
Compare the properties of the solid and liquid such as salt and oil mixing in water |
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Answer» ong>Answer: The property used in separating a mixture of TWO SOLIDS by winnowing is ( a) difference in ... LIQUIDS and gases. Solids such as salt, liquids such as ALCOHOL and gases such as NITROGEN and oxygen can dissolve in water. |
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| 7. |
To remove leaves from swimming pool what is the separation technique |
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Answer» ONG>Answer: 1.Separating funnel 2.Simple distillation 3.Simple distillation Explanation: THREE was :D |
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| 8. |
Determine the concentration of 150ml 0.550M HCl + 250ml H2O |
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Answer» ONG>ANSWER:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb ffffffffffffffffffffffffffffffffffffbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb Explanation:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb |
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| 9. |
SOLVE THE EQUATION H^2SO^4 +2NaOH=Na^2SO^4+2H^2O |
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Answer» is a NATURALISATION reaction. also this is a DISPLACEMENT reaction. plz.. MARK me the BRAINLIEST. |
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| 10. |
First order reaction |
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Answer» ong>Answer: Heya! here's the answer A first-order REACTION is a reaction that proceeds at a rate that DEPENDS linearly on only one reactant concentration. hope it HELPS Have a good day AHEAD ☺☺❤❤ |
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| 11. |
What are actinides? Why are they so called? |
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Answer» ONG>Answer: Actinides are the 15 elements with atomic numbers from 89 to 103. They are NAMED after the first element in the series, actinium. ... The actinides are most KNOWN for the elements uranium and plutonium which are used in nuclear reactors and nuclear bombs. please mark it as brainliest answer |
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| 12. |
Answer the following- (a) n+l value for 14 th electron in an atom.(b) m value for last electron of Mg atom,(c) Subshell in which last electronis present in Ga,(d) increasing order of filling electrons in 4f, 5p, 6d.(e) is 3f subshell possible? |
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Answer» ONG>Answer: don't no #-#+#-₹+#-#-#&@Mark me as brainlist |
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| 13. |
Match the column I with column ll and mark the appropriate choice. Column II 5.29 xn2 Z (A) (i) (B) h 4am Column 1 Uncertainty of an object Bohr's radius of an orbit Angular momentum of an electron De Broglie wavelength h (C) mv (D) (iv) n. 270 |
| Answer» ONG>ANSWER: | |
| 14. |
For an endothermic reaction, X----> |
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Answer» ONG>Explanation: Here, Energy for forward REACTION > Energy for BACKWARD reaction
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| 16. |
4. Which of the following exhibit variable valency? (a) Carbon(c) Copper(b) Calcium(d) Chlorine |
| Answer» ONG>ANSWER: | |
| 17. |
Mg +2 Ag + (0.0001M) → Mg 2+(0.130M) + 2Ag, E° =3.17V |
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Answer» ong>Answer: ANSWER Mg+2Ag+(0.0001M)⟶Mg 2+ (0.130M)+2Ag
=E o − 2 0.0591
LOG[ (AG + ) 2
(Mg 2+ )
] E cell
=8.17− 2 0.0591
log[ −8
0.130
]=2.959 V |
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| 18. |
PLEASE ANSWER THE QUESTION ... IT IS IN ATTACHMENT |
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Answer» ONG>Answer: i can SEE the attachment . if u WANT liks FOLLOW me and MARK as brainliest |
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| 19. |
If you are electrical depositing metal A on metal B you are ______ Bwith A |
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Answer» If you are ELECTRICAL DEPOSITING METAL A on metal B you are ____b__ Bwith A |
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| 20. |
The dilution test of strong acid of H2SO4 and strong base like NaOH is exothermic ? Explain this matter by an example |
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Answer» ONG>EXPLANATION: uyuyuuuuuuuuuuuuuu shutupen4jrjjej11j1jqujwjshrhychshhwjjjjjwjahahushhshshhshd |
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| 21. |
(a) Name the scientist who discovered that atomic number is the more fundamental periodic property of an element than its atomic mass.(b) Mention three main features of the modern periodic table. |
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Answer» > 1) mendelev 2) it is easy to remember and reproduce. - >this classification is BASED on the ATOMIC number which is a more fundamental property of the elements -> since the classification is based on atomic number not atomic MASS , the position of placeing ISOTOPES ONE place is fully justified
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| 22. |
Which of the following equation shows the same "twice" the enthalpy change of neutralization in the following equation HCl+NaOH → NaCl + H2O A)KOH+HCl→KCl+H2O b)H2SO4+Mg(OH)2→MgSO4 + 2H2Owith explanation |
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Answer» >
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| 23. |
It is impossible to measure thepotential of a singlesingle electrodeComment. |
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Answer» ONG>Answer: It is not possible to measure the ABSOLUTE potential of a single electrode because neither the oxidation nor the reduction reaction can OCCUR by itself. |
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| 24. |
It's question of balancing chemical equation H2O2 ____H2O+O2please can someone genius can answer me?sorry friends I am disturbing you but I'm glad to have friends like you |
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Answer» 2H2O2--> 2H2O + O2 |
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| 25. |
What is a pure substance ? |
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Answer» ong>ANSWER: A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references ADD that chemical substance cannot be separated into its CONSTITUENT elements by physical separation methods, i.e., WITHOUT breaking chemical bonds. |
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| 26. |
Can someone tell whats in the photo, its serious |
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Answer» ong>Explanation: NF3 the NITROGEN is more electro negative then fluorine. Nitrogen CONTAIN lone pair of electron. this compound is like CF3. SP3 HYBRIDIZED. |
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| 27. |
How does the modern periodic table overcame the limitations of Mandaleev's Periodic Table? Correct answer will be marked as brainliest answer and I will follow them. Please keep the answer on the basis of 10th class textbook. |
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Answer» ONG>Answer: Limitations of Mendeleev's Periodic Table: This law states that the physical and chemical properties of the elements are the periodic function of their atomic masses. Modern Periodic Law of element MAY be defined as the Physical and chemical properties of the elements are periodic functions of their atomic numbers. It means, when the elements are ARRANGED in the order of their increasing atomic numbers. Explanation: mark me as BRAINLISTS |
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| 29. |
श्न 3. विद्युत् रासायनिक श्रेणी पर संक्षिप्त टिप्पणी लिखिये।मागर 2006: उज्जैन 0०ीवा |
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Answer» ONG>ANSWER: जब तत्वो को उनके मानक अपचयन विभव के आरोही क्रम मे व्यवस्त्थित करते हैं तो इस प्रकार प्राप्त हुइ श्रेणी विद्युत रासायनिक श्रेणी कहलाती है। इनका उपयोग विद्युतरासायनिक सेल (ELECTROCHEMICAL CELL) (गैल्वानिक सेल) का विभव ज्ञात करने के लिये किया जा सकता है। |
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| 30. |
How many moles of oxygen atoms are present in one mole of acetic acid ?(A) 1 mole(B) 3 moles(C) 2 moles(D) 6 moles |
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Answer» ong>Answer: |
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| 31. |
Electronegativity of some elements are given [Ca = 1.0, O = 3.5, C = 2.5, S = 2.58, H = 2.2Find out whether they are ionic or covalent co2 so2and H2o |
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Answer» ong>ANSWER: They all will FORM covalent bond |
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| 32. |
Is heating of sodium hydride a redox reaction? |
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Answer» ong>Answer:Sodium hydride is the chemical compound with the EMPIRICAL formula NaH. This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis. NaH is representative of the saline hydrides, meaning it is a salt-like hydride, composed of Na+ and H− ions, in contrast to the more molecular hydrides such as borane, methane, ammonia and water. It is an IONIC material that is insoluble in organic solvents (although soluble in molten Na), consistent with the fact that H− remains an unknown anion in solution. Because of the insolubility of NaH, all reactions involving NaH occur at the surface of the solid. Contents 1 Basic properties and structure 1.1 "Inverse sodium hydride" 2 Applications in organic synthesis 2.1 As a strong base 2.2 As a reducing agent 2.3 Hydrogen storage 3 Practical considerations 4 Safety 5 References 6 Cited sources Basic properties and structure NaH is produced by the direct reaction of hydrogen and liquid sodium.[6] Pure NaH is colorless, although samples generally appear grey. NaH is ca. 40% denser than Na (0.968 g/cm3). NaH, like LiH, KH, RbH, and CsH, adopts the NaCl crystal structure. In this motif, each Na+ ion is surrounded by six H− centers in an octahedral geometry. The ionic radii of H− (146 pm in NaH) and F− (133 pm) are comparable, as judged by the Na−H and Na−F distances.[7] "Inverse sodium hydride" A very unusual situation occurs in a compound dubbed "inverse sodium hydride", which CONTAINS Na− and H+ ions. Na− is an alkalide, and this compound differs from ordinary sodium hydride in having a much higher energy content due to the net displacement of two electrons from hydrogen to sodium. A derivative of this "inverse sodium hydride" arises in the presence of the base adamanzane. This molecule irreversibly encapsulates the H+ and shields it from interaction with the alkalide Na−.[8] Theoretical work has suggested that even an unprotected protonated tertiary amine complexed with the sodium alkalide might be metastable under certain solvent conditions, though the barrier to reaction would be small and finding a suitable solvent might be difficult.[9] Applications in organic synthesis As a strong base NaH is a base of wide scope and utility in organic chemistry.[10] As a superbase, it is capable of deprotonating a range of even weak Brønsted acids to give the corresponding sodium derivatives. Typical "easy" substrates contain O-H, N-H, S-H bonds, including alcohols, phenols, pyrazoles, and thiols. NaH notably deprotonates carbon acids (i.e., C-H bonds) such as 1,3-dicarbonyls such as malonic esters. The resulting sodium derivatives can be alkylated. NaH is widely used to promote condensation reactions of carbonyl compounds via the Dieckmann condensation, Stobbe condensation, Darzens condensation, and Claisen condensation. Other carbon acids susceptible to deprotonation by NaH include sulfonium salts and DMSO. NaH is used to make sulfur ylides, which in turn are used to convert ketones into epoxides, as in the Johnson–Corey–Chaykovsky reaction. As a reducing agent NaH reduces certain main group compounds, but analogous reactivity is very rare in organic chemistry (see below).[11] Notably boron trifluoride reacts to give diborane and sodium fluoride:[6] 6 NaH + 2 BF3 → B2H6 + 6 NaF Si-Si and S-S bonds in disilanes and disulfides are also reduced. A series of reduction reactions, including the hydrodecyanation of tertiary nitriles, reduction of imines to amines, and amides to aldehydes, can be effected by a composite reagent composed of sodium hydride and an alkali metal iodide (NaH:MI, M = Li, Na).[12] Hydrogen storage Although not commercially significant sodium hydride has been proposed for hydrogen storage for use in fuel cell vehicles. In one experimental implementation, plastic pellets containing NaH are crushed in the presence of water to release the hydrogen. One challenge with this technology is the regeneration of NaH from the NaOH.[13] Practical considerations Sodium hydride is sold as a mixture of 60% sodium hydride (w/w) in mineral oil. Such a dispersion is safer to handle and weigh than pure NaH. The compound is often used in this form but the pure grey solid can be prepared by rinsing the commercial product with pentane or THF, with care being TAKEN because the waste solvent will contain traces of NaH and can ignite in air. Reactions involving NaH require air-free techniques. Typically NaH is used as a suspension in THF, a solvent that resists attack by strong bases but can solvate many reactive sodium compounds. Safety NaH can ignite in air, especially upon contact with water to release hydrogen, which is also flammable. Hydrolysis converts NaH into sodium hydroxide (NaOH), a caustic base. In practice, most sodium hydride is dispensed as a dispersion in oil, which can be safely handled in air.[14] Explanation:Pls mark the brainliest |
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| 33. |
ক্যালসিয়াম ফসফেট যৌগটি তে ফসফরাসের শতকরা পরিমাণ কত? ca=40,p=31,O=16 |
Answer» ONG>ANSWER:
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| 35. |
Nh4cl ke chaliye billion ka litmus patr par kya prabhav pada |
Answer» ALIGN="absmiddle" alt="\huge \pink\star{ \green{ \boxed{ \boxed{{ \orange{ \mathfrak{ Answer}}}}}}}\pink \star" class="latex-formula" id="TexFormula1" src="https://tex.z-dn.net/?f=%5Chuge%20%5Cpink%5Cstar%7B%20%5Cgreen%7B%20%5Cboxed%7B%20%5Cboxed%7B%7B%20%5Corange%7B%20%5Cmathfrak%7B%20%20Answer%7D%7D%7D%7D%7D%7D%7D%5Cpink%20%5Cstar" title="\huge \pink\star{ \green{ \boxed{ \boxed{{ \orange{ \mathfrak{ Answer}}}}}}}\pink \star">
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| 36. |
Discuss the Conductometric titration |
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Answer» ong>Explanation: tggdhj |
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| 37. |
How can we separate potassium nitrate and sodium chloride dissolved in water? Other than fractional crystallization, what other separation techniques can be used to remove the 2 different kinds of salt (potassium nitrate and sodium chloride)? |
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Answer» ong>Explanation:P> Find the value of m so that the quadratic EQUATION px^2 + (p – 1) X +(p – 1) = 0 has EQUAL roots. |
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| 38. |
How many electron satisfyin n+1 =5 |
| Answer» ONG>EXPLANATION: | |
| 39. |
How many litres of oxygen will produce by decomposition of 112 litres of ozone at STP |
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Answer» ONG>Answer: 15 litres
Explanation: This is because of the formula:
mole = volume of STP22.4thats why the formula should be written as
Given:ozone = 3O i.e. 3 molecules of oxygen. volume must be = 112×3 = 336 So, as per formula
mole = 336 22.4 = 15 litres. So , 15 litres of oxygen will produce by DECOMPOSITION of 112 litres of ozone at STP. |
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| 40. |
define azeotropes.what type of azeotrope is formed by positive deviation from roults law?give an example and graph |
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Answer» ong>Answer: SORRY, I am CLASS 9th, I can't help.... Explanation: But WAIT, MARK ME THE BRAINLIEST :-) |
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| 41. |
How many NMR signals are shown by 1,3,5-trimethyl cyclohexane. |
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Answer» 5-TRIMETHYLCYCLOHEXANE 1839-63-0 NMR SPECTRUM, 1,3,5-TRIMETHYLCYCLOHEXANE H-NMR SPECTRAL ANALYSIS, 1,3,5-TRIMETHYLCYCLOHEXANE .. |
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| 42. |
Alizarin dye contains ......................chromophoric groups 1) >C=N-- 2) =C=O and =C=C 3) >C=NH and >C=N- 4) -N=O, >N—OH |
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Answer» ONG>Answer: 4) -N=O, >N—OH Explanation: |
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| 43. |
Compare the properties of True solution ,colloid and suspension based on i) size of particle ii) filterability iii) Nature |
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Answer» ong>Explanation: True SOLUTION: a MIXTURE of two or more substances in which the solute is completely DISSOLVE in the solvent. The size of particles in a true solution will be less than 1 nm in diameter. (2). ... The size of particles in a colloidal solution will be larger than that of a true solution and smaller than suspension. please mark it as brainliest answer..... |
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| 44. |
How does valence bond theory explain the shapes and magnetic properties of four-coordinated complexes of Ni*? |
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Answer» ong>Answer: The valence bond theory EXPLAINS the structure and magnetic properties of a LARGE NUMBER of coordination compounds. Valence bond theory was used to EXPLAIN the structure of coordination compounds and the bond linkages. According to valence bond theory, the METAL atom |
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| 45. |
which of the following produces H2 gas ,when reacts with acid? a)zn. b)s. c)C. d)O2 |
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Answer» er: B) s (Sulphate) Explanation: When a reactive metal reacts with HYDROCHLORIC ACID hydrogen gas is produced A reactive metal displaces the hydrogen from acid and release hydrogen gas. (b) sulphate Please follow me guys and MARK me as Brainliest and please SUPPORT me |
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| 46. |
What is the definition of the organomettalic compounds? Please give the explanation for it... |
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Answer» ong>EXPLANATION: Organometallic compound, any member of a class of substances containing at least one metal-to-carbon bond in which the carbon is PART of an organic group. ... The class INCLUDES such compounds as ferrocene, a REMARKABLY stable compound in which an iron atom is sandwiched between TWO hydrocarbon rings. |
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| 47. |
fresh milk has a pH of 6. when it change into curd (yogurt) will its PH value increase or decrease? why? |
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Answer» ong>ANSWER: it will decrease Explanation: |
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| 49. |
Any substances that promotes phagocytosis of antigens by binding to them are called as a) Opsonins b) Phagocytosis c) Macrophages d) Interleukins |
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Answer» ER: Hey mate hope it is helpful Explanation: Option A- Oposonins An opsonin (from the Greek opsōneîn, to PREPARE for eating) is any molecule that enhances phagocytosis by marking an antigen for an IMMUNE RESPONSE or marking dead cells for recycling (i.e., causes the phagocyte to "RELISH" the marked cell). |
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| 50. |
Give the formulae of the compounds formed from the following sets of elements (a) Calcium and fluorine (b) Hydrogen and sulphur (c) Nitrogen and hydrogen (d) Sodium and oxygen |
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Answer» ANSWER 1. Calcium and FLUORINE Symbol Ca F Charges +2 1− Formula CaF2 2. Hydrogen and SULPHUR Symbol H S Charges 1+ 2− Formula H2S 3. NITROGEN and hydrogen Symbol N H Charges 3− 1+ Formula NH3 4. Carbon and chlorine Symbol C Cl Charges 4+ 1− Formula CCl4 5. Sodium and oxygen Symbol Na O Charges 1+ 2− Formula Na2O 6. Carbon and oxygen. Symbol C O Charges 4+ 2− C2O4 i. e. Formula CO2 |
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