The substance used as a smoke screen in warfare is
(A) C2H2
(B) SiCl4
(C) P2O5
(D) PCl5

1 Answer

Answer :

Option B

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Last Answer : (C) P2O5

Description : Acetamide can be converted into methylamine by (a) P2O5 (b) Br2/NaOH (c) PCl5 (d) LiAlH4

Last Answer : Br2/NaOH

Description : What are electron deficient compounds? AreBCl3 and SiCl4 electron deficient species? Explain.

Last Answer : Ans. Electron deficient species are those in which the central atom in their molecules as the tendency to accept on or more electron pairs. They are also known as Lewis acids .BCl3 and SiCl4 ... due to the presence of d-orbital. Thus .SiCl4 should also be considered as electron deficient spaces.

Description : In Call of Duty Modern Warfare 2, can you do any split screen playing? Either online or campaign?

Last Answer : I believe you can only play split screen (& 2 player in general) in Co ops.

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Last Answer : YES!!!!!!

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Last Answer : (A) CH4

Description : Gross calorific value will be equal to the net calorific value for (A) H2 (B) C2H2 (C) CO (D) C2H6

Last Answer : (C) CO

Description : Pick out the exothermic reaction out of the following: (A) C + H2O = CO + H2 (B) CaC2 + H2O = Ca(OH)2 + C2H2 (C) MgCO3 = MgO + CO2 (D) All (A), (B) and (C)

Last Answer : (B) CaC2 + H2O = Ca(OH)2 + C2H2

Description : Producer gas consists mainly of (A) CO, CO2 N2 , H2 (B) CO, H2 (C) H2 , CH4 (D) C2H2 , CO2 , H2

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Description : A phosphatic fertiliser contains 16% P2O5 . It could be (A) Dicalcium phosphate (B) Superphosphate (C) Triple superphosphate (D) None of these

Last Answer : (B) Superphosphate

Description : P2O5 content in triple superphosphate is about __________ percent. (A) 42-50 (B) 15-20 (C) 85-90 (D) 70-75

Last Answer : (A) 42-50

Description : Base suspension fertiliser essentially contains (A) 13% N2 and 43% P2O5 (B) 43% N2 and 13% P2O5 (C) 43% N2 and 13% K2O (D) 43% K2O and 43% P2O5

Last Answer : (A) 13% N2 and 43% P2O5

Description : P2O5 content in superphosphate is about __________ percent. (A) 30-35 (B) 15-20 (C) 65-70 (D) 85-90

Last Answer : (B) 15-20

Description : Triple superphosphate which contains about 46% P2O5 is produced by the reaction of phosphate rock with ortho phosphoric acid of________ percent concentration. (A) 25-28 (B) 52-54 (C) 75-80 (D) > 98

Last Answer : (B) 52-54

Description : P2O5 percentage in the phosphoric acid produced by wet process is about (A) 10 (B) 30 (C) 50 (D) 70

Last Answer : (B) 30

Description : 5-10-5 fertilisers mean that they contain (A) 5, 10, 5% respectively of N2 , P2O5 and K2O (B) Only 5 to 10% active fertiliser constituents (C) 5 to 10% filler & carrier of soil conditioners (D) None of these

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Description : In the decomposition of PCl5 represented by, PCl5 ⇌ PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5. (A) Increase (B) Decrease (C) Not alter (D) None of these

Last Answer : (A) Increase

Description : Pick out the wrong statement pertaining to the decomposition of PCl5 represented by, PCl5 ⇌ PCl3 + Cl2.Degree of dissociation of PCl5 will (A) Decrease on addition of Cl2 (B) Increase on addition of ... at constant pressure (C) Decrease on increasing the pressure of the system (D) None of these

Last Answer : (D) None of thes

Description : Ammonia gas can be dried by (A) PCl5 (B) Quick lime (C) CaCl2 (D) Concentrated H2SO4

Last Answer : (B) Quick lime

Description : How much co2 is produced when 4000g of c2h2 burns completely?

Last Answer : Need answer

Description : What is the order of C-H bond length in C2H6 and C2H4 and C2H2 ?

Last Answer : c2h6>c2h4 >c2h2

Description : In its reaction with silver nitrate, C2H2 shows – (1) Oxidising property (2) Reducing property (3) Basic property (4) Acidic property

Last Answer : (4) Acidic property Explanation: When treated with ammoniacal silver nitrate solution alkynes form white precipitate of silver acetylides.

Description : Compound having tetrahedral structure is ______. (1) C2H4 (2) C2H2 (3) CH4 (4) None of these

Last Answer : (3) CH4 Explanation: Methane is a tetrahedral molecule with four equivalent C-H bonds. Its electronic structure is described by four bonding molecular orbital resulting from the overlap of the valence orbitals on C and H.

Description : Arrange the following in the increasing order of C-C bond length- C2H6 , C2H4, C2H2

Last Answer : Ans. C2H2 < C2H4 < C2H6

Description : Point group C2v belong to the molecule a. H2O b. BeH2 c. NH3 d. C2H2

Last Answer : a. H2O

Description : The triple bond between the carbon atoms causes acetylene, C2H2, to have which of the following shapes? w) trigonal planar (pron: try-gon-al) x) linear y) tetrahedral z) trigonal bipyramidal

Last Answer : ANSWER: X -- LINEAR

Description : In its reaction with silver nitrate, C2H2 shows (1) Oxidising property (2) Reducing property (3) Basic property (4) Acidic property

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Description : The relative percentage of N2 , P2O5 and K2O” in a fertilizer

Last Answer : Ans. Fertilizer ratio

Description : Fertilizers contain more than 25% of primary nutrients, e.g. Urea (46%), DAP (18% N and 46% P2O5 ).

Last Answer : Ans. High analysis fertilizers

Description : Which of the following is correct for calculating PHOSPHOROUS in P2O5 fertilizer? (a) P2O5 × 0.44 = P (b) P2O5 × 2.29 = P (c) P2O5 × 0.83 = P (d) P2O5 × 1.20 = P

Last Answer : (a) P2O5 × 0.44 = P

Description : By which of the following methods can CH3CONH2 be converted to CH3CN? (a) Oxidize with Na2Cr2O7/H+ (b) Heat with concentrated sulfuric acid (c) Heat to 200°C (d) Warm with P2O5

Last Answer : Warm with P2O5

Description : Which of the following statements is False about acetamide? (a) reacts with Br2/NaOH to form tertiary amine (b) undergoes acid-hydrolysis to form acetic acid (c) undergoes dehydration with P2O5 to form a nitrile (d) is a white crystalline solid, soluble in water

Last Answer : reacts with Br2/NaOH to form tertiary amine

Description : Acetamide on heating with P2O5 gives : (a) Methylamine (b) Ethylamine (c) Methyl cyanide (d) None of these

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Description : Acetic anhydride is obtained by the reaction of : (a) Acetic acid and sodium (b) Acetic acid and water (c) Acetic acid and diethyl ether (d) Acetic acid and P2O5

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Description : The percentage of P2O5 in diammonium hydrogen phosphate (NH4)2HPO4 is [CPMT 1992] (A) 23.48 (B) 46.96 (C) 53.78 (D) 71.00

Last Answer : (C) 53.78

Description : What is the name of the compound with the formula PCl5 ?

Last Answer : Phosphorus pentachloride

Description : What happens to the dissociation of PCl5 in a closed vessel if He gas is introduced into it at the same temperature?

Last Answer : Ans. No effect.

Description : Explain why PCl5 is trigonal bipyramidal and IF5is square pyramidal?

Last Answer : Ans. PCl5 has 5 bond pairs of electrons around central atom while in IF5 there are 5 bond pair & 1 lone pair of electrons around central atom.

Description : Are all the five bonds in PCl5 molecule equivalent ? 

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Description : Compound (A) when reacted with PCl5 and then with ammonia gave (B). Compound (B) when treated with bromine and NaOH, produced (C). Compound (C) on treatment with NaNO2/HCl at 0°C and then boiling with H2O ... Compound (A) is (a) o-Toluic acid (b) o-Chlorotoluene (c) m-Toluic acid (d) o-Bromotoluene

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Description : Which of the following compounds will react with PCl5 least vigorously? (a) Ethanol (b) Acetic acid (c) Phenol (d) Benzoic acid

Last Answer : Phenol

Description : Which of the following reagents will react with acetamide to form methylamine? (a) LiAlH4 (b) Br2/NaOH (c) PCl5 (d) H2/Ni

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Description : Butyric acid reacts with PCl5 to give (a) Benzoyl chloride (b) 1-Chlorobutane (c) Butyryl chloride (d) 1-Chloropropane

Last Answer : Butyryl chloride

Description : Organic compound (A), C4H8O, does not react with sodium or PCl5. However, it reduces an alkaline solution of a copper (II) salt on heating. Compound (A) could be (a) an aldehyde (b) a primary alcohol (c) a ketone (d) a secondary alcohol

Last Answer : an aldehyde

Description : Ethylene glycol reacts with excess of PCl5 to give (a) Chloroethane (b) 1,2-Dichloroethane (c) Hexachloroethane (d) 1,3-Dichloroethane

Last Answer : 1,2-Dichloroethane

Description : Which of the following reaction mixtures will give an organic product which is ionic? (a) CH3CH2OH + PCl5 (b) CH3CH2OH + KBr + H2SO4 (c) CH3CH2OH + Na (d) CH3CH2OH + SOCl2

Last Answer : CH3CH2OH + Na

Description : Which of the following reagents cannot be used to prepare an alkyl chloride from an alcohol? (a) HCl + ZnCl2 (b) SOCl2 (c) NaCl (d) PCl5

Last Answer : NaCl

Description : How the change in pressure at equilibrium position effect the following reaction? PCl5 PCl3 + Cl2

Last Answer : According to Le–chatlier’s principle, by increasing pressure the reaction will move toward less number of moles. In the above reaction, by increasing pressure the reaction will move in backward direction.

Description : Consider the following gaseous equilibrium: PCl3 + Cl2 = PCl5 + heat. Which of the following changes will shift it to the right: w) lower the temperature x) remove some Cl2 y) increase the volume z) add a catalyst

Last Answer : ANSWER: W -- LOWER THE TEMPERATURE

Description : What is the hybridization assumed for phosphorus in PCl5?

Last Answer : ANSWER: d sp3