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
Answer:
5.2g copper (Cu) => 0.082 moles copper (2 sig.figs.)
Explanation:
mole conversions:
grams to moles => divide by formula wt.
moles to grams => multiply by formula wt.
gas volumes to moles => divide volume by 22.4Liters/mole (STP conditions only)
This problem:
mass to moles => divide by formula wt.
mass = 5.2g = 5.2g/63.5g/mole = 0.082 moles copper (2 sig.figs.)
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