MCQ on NMR spectroscopy: Page-12

The units for gyro magnetic ratio are

(A) Tesla. sec ^-1

(B) Radian .tesla ^-1. sec ^-1

(C) Radian .sec ^-1

(C) No units

At 4.69 T magnetic field strength, The excess number of nuclei in ground state are

(A) 469 ppm

(B) 235 ppm

(C) 33 ppm

(C) 66 ppm

The optimum life time of an excite nucleus for NMR absorption is

(A) 0.1 to 0.01 sec

(B) 1 to 10 sec

(C) 0.1 to 10 sec

(C) 0.01 to 0.1 sec

The longitudinal relaxation decreases with

(A) Very high mobility of lattice

(B) Very low mobility of lattice

(C) Medium mobility of lattice

(C) All of the above

The transition of energy of excited nucleus to neighbouring nuclei is known as

(A) Transverse relaxation

(B) Longitudinal relaxation

(C) Vibrational relaxation

(C) Thermal relaxation