Description : Which type of intermolecular forces exists among the following molecules? (a) H2S molecules (b) H2O (c) Cl2 and CCl4 (d) SiH4 (e) Helium (f) He atoms and HCl molecules
Last Answer : Ans. (a) Dipole-Dipole interactions. (b)H-Bond. (c)Dispersion forces. (d)Dispersion forces. (e)Dispersion forces. (f)Induced dipole-dipole interactions.
Description : Which of the following pairs of compounds will not form hydrogen bonds with each other? (a) CH3OH and CH3CH2OH (b) CH3SH and CH3CH2SH (c) CH3OCH3 and CH3CH2OCH2CH3 (d) CH3COOH and H2O
Last Answer : CH3OCH3 and CH3CH2OCH2CH3
Description : The compound in which hydrogen bonding is not possible is (a) CH3OCH3 (b) H2O (c) CH3CH2OH (d) CH3COOH
Last Answer : CH3OCH3
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 : Most covalent compounds (a) Behave like electrolytes in the molten state (b) Have high melting and boiling points (c) Are hard substances because of strong covalent bonds (d) Are more soluble in non-polar solvents than in polar solvents
Last Answer : Ans:(d)
Description : Which of the following reagents will react with pyrrole to form 2- formylpyrrole? (a) HCOOH (b) CHCl3/KOH (c) H2O2 (d) (CH3CO)2O/SnCl4
Last Answer : CHCl3/KOH
Description : Why does the boiling point of CH3NH2 less than HCOOH?
Last Answer : Ans:- HCOOH is associated with intermolecular H-bonding in greater extent then CH3NH2 and therefore HCOOH has higher boiling point than CH3NH2 .
Description : Why HCOOH does not give HVZ (Hell Volhand Zelinsky) reaction but CH3COOH does ?
Last Answer : Ans. CH3 COOH contains hydrogens and hence give HVZ reaction but HCOOH does not contain -hydrogen and hence does not give HVZ reaction.
Description : Which compound has the highest boiling point? (a) CH3CH3 (b) CH3OCH3 (c) CH3CH2OH (d) CH3COOH
Last Answer : CH3COOH
Description : The compound with the lowest boiling point is (a) H2O (b) CH3CH2OH (c) CH3OCH3 (d) CH3CH2CH3
Last Answer : CH3CH2CH3
Description : Which of the following is the best nucleophile in water? (a) I– (b) CH3SCH3 (c) CH3OCH3 (d) Cl–
Last Answer : I–
Description : Which of the following has the greatest solubility in CH3CH2CH2CH3? (a) CH3OH (b) CH3NH2 (c) CH3OCH3 (d) (CH3)3CH
Last Answer : (CH3)3CH
Description : Ethanol (CH3CH2OH) and dimethyl ether (CH3OCH3) are best considered : (a) structural isomers (b) stereoisomers (c) enantiomers (d) diastereomers
Last Answer : structural isomers
Description : Which of the following are Lewis bases? (a) NF3 (b) BF3 (c) CH3OCH3 (d) (a) and (c
Last Answer : (a) and (c
Description : Which of the following is not a nucleophile? (a) FeBr3 (b) Br– (c) NH3 (d) CH3OCH3
Description : Which of the following is a Lewis acid? (a) AlCl3 (b) CH3OH (c) NH3 (d) CH3OCH3
Last Answer : AlCl3
Description : What property of low-molecular weight aldehydes and ketones accounts for the magnitude of their boiling points? (a) The ability to form strong H-bonds between their molecules. (b) The ability of ... other polar molecules. (d) The ability of the carbonyl group to attract electrophiles and form bonds.
Last Answer : The ability of the polar carbonyl group to attract other polar molecules.
Description : The reaction `RCH_(2)CH_(2)COOH overset(Red P)underset(Br_(2))toRCH_(2)-underset(Br)underset(|)(C)HCOOH` is called as
Last Answer : The reaction `RCH_(2)CH_(2)COOH overset(Red P)underset(Br_(2))toRCH_(2)-underset(Br) ... reaction C. Reimer Teimann reaction D. Sandmeyer reaction
Description : Which is decreasing order of acidity in, `HCOOH(I), CH_(3)COOH(II), CH_(3)CH_(2)COOH(III) and C_(6)H_(5)COOH(IV)`?
Last Answer : Which is decreasing order of acidity in, `HCOOH(I), CH_(3)COOH(II), CH_(3)CH_(2)COOH( ... B. `IVgtIIIgtIIgtI` C. `IVgtIgtIIgtIII` D. `IgtIVgtIIgtIII`
Description : What is the atomic mass of HCOOH(formic acid)?
Last Answer : The molar (not atomic) mass of HCOOH (formic acid) is 46,03g.
Description : Name the acid present in Ant sting and its chemical formula. (a) Methanoic acid and HCOOH (b) Formic acid and HCOOH (c) Acetic acid and CH3COOH (d) Both a and b
Last Answer : (d) Both a and b
Description : Which group forms the strongest H-bonds to water molecules? (a) Alcohols (b) Ethers (c) Phenols (d) All equally strong
Last Answer : Phenols
Description : In 2-butene, which of the following bonds prevents the atoms at each end of the bond from rotating with respect to each other. Is it an: w) ionic bond x) sigma bond y) strong bond z) double bond
Last Answer : ANSWER: Z -- DOUBLE BOND
Description : Will CCl4 give white ppt.of AgCl on heating with AgNO3?
Last Answer : No, CCl4 being covalent compound does not give white ppt.of AgCl on heating with AgNO3
Description : NaCl gives a white ppt. with AgNO3 but CCl4 does not. Why?
Last Answer : Answer. Being an ionic compound NaCl gives Cl negative ion and thus gives White ppt. with silver nitrate but CCl4 is a covalent compound and thus do not give Cl negative ions.
Description : Which of the following reagents can be used to distinguish between chlorobenzene and benzyl chloride? (a) alcoholic AgNO3 (b) Br2 in CCl4 (c) KCN (d) Br2 in H2O
Last Answer : alcoholic AgNO3
Description : Which of the following reagents can be used to distinguish between chlorobenzene and allyl chloride? (a) H2/Ni (b) Br2 in CCl4 (c) Zn/HCl (d) NH2NH2
Last Answer : Br2 in CCl4
Description : When ethanol is heated with concentrated H2SO4, a gas is produced. Which of the following compounds is formed when this gas is treated with bromine in CCl4?E2 (a) Bromomethane (b) 1,2-Dibromoethane (c) Bromoethane (d) 1,1,2,2-Tetrabromoethane
Last Answer : 1,2-Dibromoethane
Description : 1-Butyne can be distinguished from 2-butyne by using (a) potassium permanganate (b) bromine in CCl4 (c) Tollens' reagent (d) chlorine in CCl4
Last Answer : chlorine in CCl4
Description : Ethylene and acetylene can be distinguished by using (a) Bromine in CCl4 (b) Tollens' reagent (b) Baeyer's reagent (d) Phenylhydrazine
Last Answer : Tollens' reagent
Description : Starting with 2-butene, which of the following is the best method for preparing 2-butyne? (a) HBr; H2/Ni; Zn/H+ (b) HBr; Zn/H+; H2/Ni (c) Br2/CCl4; Zn/H+; H2/Ni (d) Br2/CCl4; 2NaNH2
Last Answer : Br2/CCl4; 2NaNH2
Description : Which of the following compounds will react most readily with bromine in CCl4? (a) CH3CH2CH3 (b) (CH3)3CH (c) CH3CH=CH2 (d) (CH3)4C
Last Answer : CH3CH=CH2
Description : Baeyer's reagent is (a) dilute KMnO4 (b) HCl + ZnCl2 (c) Br2 in CCl4 (d) NH2NH2
Last Answer : dilute KMnO4
Description : A compound of formula C3H8 does not react with bromine in CCl4 in the dark. The compound could be (a) Alkane (b) Cycloalkane (c) Alkene (d) Cycloalkene
Last Answer : Alkane
Description : The chlorination of methane to give CCl4 is an example of (a) an electrophilic addition (b) a free-radical substitution (c) a nucleophilic addition (d) an electrophilic substitution
Last Answer : a free-radical substitution
Description : Which molecule has a nonzero dipole moment? (a) Cl2 (b) CO2 (c) CCl4 (d) CHCl3
Last Answer : CHCl3
Description : Which of the following molecules has a dipole moment? w) BF3 x) NH3 y) CCL4 z) CH4
Last Answer : ANSWER: B -- NH3
Description : Which of the following compounds has the lowest boiling points? w) CH4 x) CCl4 y) PH3 z) PCl3
Last Answer : ANSWER: W -- CH4
Description : Which of the following compounds has the highest boiling point? w) CH4 x) CCL4 y) HI z) IF5
Last Answer : ANSWER: Z -- IF5
Description : Which of the following substances would be expecte to have the highest melting point? w) Potassium Bromide x) Iodine y) Methane z) Hydrogen Chloride
Last Answer : ANSWER: W -- POTASSIUM BROMIDE
Description : Pick out the wrong statement. (A) Molecules with symmetrical arrangements (e.g. CH4 or CCl4) are non polar (B) Generally, non-polar compounds are chemically inactive, conduct electricity poorly and do not ionise (C) Most of the hydrocarbons are non-polar (D) None of these
Last Answer : (D) None of these
Description : How many hydrogen bonds are there in the dimer formation of ethanoic acid ?
Last Answer : Answer : Ethanoic acid has two hydrogen bonds in its dimer structure.
Description : The number of hydrogen bonds between guanine and cytosine in DNA is – (1) 2 (2) 3 (3) 4 (4) 1
Last Answer : (2) 3 Explanation: The chemistry of the nitrogenous bases is really the key to the function of DNA. It allows something called complementary base pairing. Cytosine can form three hydrogen bonds with guanine, and adenine can form two hydrogen bonds with thymine.
Description : Benzene undergoes substitution reaction more easily than addition reaction because (a) it has a cyclic structure (b) it has three double bonds (c) it has six hydrogen atoms (d) there is delocalization of electrons
Last Answer : there is delocalization of electrons
Description : The double helical structure of DNA is held together by (a) sulfur-sulfur linkages (b) peptide bonding (c) hydrogen bonding (d) glycosidic bonds
Last Answer : hydrogen bonding
Description : Why do alcohols have boiling points much higher than hydrocarbons of similar molecular weight? (a) Alcohols have greater van der Waals attraction forces. (b) Alcohol molecules have greater ... of volatilization. (d) Alcohols must overcome greater ionic forces in the process of volatilization.
Last Answer : Hydrogen bonds must be broken in the process of volatilization
Description : The higher reactivity of an alkene or alkyne, as compared to an alkane, is due to (a) sigma bonds (b) pi bonds (c) hydrogen bonds (d) None of these
Last Answer : pi bonds
Description : A family of organic compounds containing only carb and hydrogen and having only single bonds are the: w) alkenes and alkanes x) alkanes and cycloalkanes y) alkynes (pron: AL-kines) and alkenes z) cycloalkanes and alkenes
Last Answer : ANSWER: B -- ALKANES AND CYCLOALKANES
Description : The angle between any two carbon-hydrogen bonds in a methane molecule is how many degrees?
Last Answer : ANSWER: 109.5 DEGREES