A 600 W mercury lamp emits monochromatic radiation of wavelength 331.3 nm. How many photons are emitted from the lamp per second? (h = 6.626x 10-34 J-s; velocity of light = 3x108 ms-1)
1 x 1019
1 x 1020
1 x 1021
1 x 1023
Which of the following relation is correct ?
Ist IE of C > Ist IE of B
Ist IE of C < Ist IE of B
IInd IE of C > IInd IE of B
Both (b) and (c)
A.
Ist IE of C > Ist IE of B
The minimum amount of energy required to remove the most loosely bound electron from an isolated gaseous atom so as to convert it into a gaseous cation, is called its ionisation energy. Because the size of C is smaller than that of the B due to effective nuclear charge, hence
Ist IE of C > Ist IE of B
Considering H2O as weak field ligand, the number of unpaired electrons in [Mn(H2O)6] will be (Atomic number of Mn = 25)
five
two
four
three
The quantum numbers + and - for the electron spin represent
rotation of the electron in clockwise and anticlockwise direction respectively
rotation of the electron in anticlockwise and clockwise direction respectively
magnetic moment of the electron pointing up and down respectively
two quantum mechanical spin states which have no classical analogues
What is the wave number of 4th line in Balmer series of hydrogen spectrum ? (R =1,09,677 cm-1)
24630 cm-1
24360 cm-1
24730 cm-1
24372 cm-1
The de-Broglie wavelenght of a particle with mass 1 kg and velocity 100 m/s is
6.6 x 10-33 m
6.6 x 10-36 m
3.3 x 1033 m
3.3 x 10-36 m