Questions for 22-10-2007

1.

STATEMENT-1: Molecules that are not superimposable on their mirror images are chiral.

Because

STATEMENT-2: All chiral molecules have chiral centres.

(A) Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1
(B) Statement-1 is True, Statement-2 is True; Statement-2 is not a correct explanation for Statement-1
(C) Statement-1 is True, Statement-2 is False
(D) Statement-1 is False, Statement-2 is True




2. In the experiment to determine the speed of sound using a resonance column,
(A) prongs of the tuning fork are kept in a vertical plane
(B) prongs of the tuning fork are kept in a horizontal plane
(C) in one of the two resonances observed, the length of the resonating air column is close to the wavelength of sound in air
(D) in one of the two resonances observed, the length of the resonating air column is close to half the wavelength of sound in air



3. If a, b, c be unit vectors such that a + b + c = 0. Which one of the following is correct?
(A) a × b = b × c = c × a = 0
(B) a × b = b × c = c × a is not equal to 0
(C) a × b = b × c = a × c is not equal to 0
(D) a × b, b × c, c × a are mutually perpendicular