Explanation:
to find the number of moles for tetracycline you use the formula,
number of moles=mass/molar mass
the mass is given in the question which is 71.9g and the molar mass is 444.43(you find I by adding the number of atoms for each element in the compound,12×22+1×24+14×2+16×8)
n=71.9g/444.43
=0.16g/mol
I hope this helps
