Formal charge can be calculated from the following formula
Formal charge = valency of central atom - (number of lone pair of electrons + number of covalent bonds)
a) for methylene:
Formal charge = 4 -( 2+ 2) = 0
b) For methyl free radical
Formal charge = 4- (3 +1) = 0
The range for em radiation should be a range of 50 yards hope this help's. <span />
Centimeters are units of length.
