The correct answer is
Energy of electrons depends on light’s frequency, not intensity.
As per photoelectric effect, if we incident a light on metal surface it will results into emission of electron from it
if we increase the number of photons the number of electrons will increase however if we increase the frequency the number of photons will not increase
While if we increase frequency the energy of electrons will increase as
Energy of photon = Work function of metal + kinetic energy of electrons
Seismic waves hope this helps.
N -3
Ba +2
Sr +2
F -1
I -1
Ca +2
Mg +2
S -2
S -2
Al +3
//
Ba3N2
SrF2
CaI2
MgS
Al2S3
//
I don't really understand 2.
Atomic mass Hg = 200.59 u.m.a
200.59 g --------------- 6.02x10²³ atoms
( mass Hg ) ----------- 1.20 x10²² atoms
mass Hg = ( 1.20x10²² ) x 200.59 / 6.02x10²³
mass Hg = 2.407x10²⁴ / 6.02x10²³
= 3.998 g of Hg
hope this helps!