Answer is: requirement of valine is 0,0222 mol for a100 kilograms adult.
m(C₅H₁₁NO₂) = 2,60 g.
M(C₅H₁₁NO₂) = 5 · 12 + 11 · 1 + 1 · 14 + 2 · 16 · g/mol.
M(C₅H₁₁NO₂) = 117 g/mol.
n(C₅H₁₁NO₂) = m(C₅H₁₁NO₂) ÷ M(C₅H₁₁NO₂).
n(C₅H₁₁NO₂) = 2,60 g ÷ 117 g/mol.
n(C₅H₁₁NO₂) = 0,0222 mol.
n - amount of substance.
m - mass of substance.
M - molar mass of substance.