Calculate the molecular mass of the following in u. a. NH3 b. CH3COO

1.	Calculate the molecular mass of the following in u. a. NH3 b. CH3COOH c. C2H5OH
Answer» (a) Molecular mass of NH₃ = (1 × Average atomic mass of N) + (3 × Average atomic mass of H) = (1 × 14.0 u) +(3 × 1.0 u) = 17 u (b) Molecular mass of CH₃COOH = (2 × Average atomic mass of C) + (4 × Average atomic mass of H) + (2 × Average atomic mass of O) = (2 × 12.0 u) + (4 × 1.0 u) + (2 × 16.0 u) = 60 u (c). Molecular mass of C₂H₅OH = (2 × Average atomic mass of C) + (6 × Average atomic mass of H) + (1 × Average atomic mass of O) = (2 × 12.0 u) + (6 × 1.0 u) + (1 × 16.0 u) = 46 u

Calculate the molecular mass of the following in u. a. NH3 b. CH3COOH c. C2H5OH

Answer»

(a) Molecular mass of NH₃ = (1 × Average atomic mass of N) + (3 × Average atomic mass of H)

= (1 × 14.0 u) +(3 × 1.0 u)

= 17 u

(b) Molecular mass of CH₃COOH = (2 × Average atomic mass of C) + (4 × Average atomic mass of H) + (2 × Average atomic mass of O)

= (2 × 12.0 u) + (4 × 1.0 u) + (2 × 16.0 u)

= 60 u

(c). Molecular mass of C₂H₅OH = (2 × Average atomic mass of C) + (6 × Average atomic mass of H) + (1 × Average atomic mass of O)

= (2 × 12.0 u) + (6 × 1.0 u) + (1 × 16.0 u)

= 46 u