Question

1. Calculate the molar mass for Mn2O7, an oxide of manganese. Express your answer to five significant figures.

2.Calculate the molar mass of acetylcholine (C7NH16O2), a neurotransmitter that activates muscles. Express your answer to five significant figures.

PLEASE HELP..THnks!

Answer 1

Mn has atomic mass 54.938 g/mol , O has atomic mass of 15.999 g/mol

Molar mass of Mn2O7 = (2 x atomic mass of Mn) + ( 7 x atomic mass of O)

           = ( 2 x 54.938) + ( 7 x 15.999)

         = 221.87 g/mol

2) C has atomic mass 12g/mol, H has atomic mass 1.0078 g/mol , N has atomic mass 14.0067 g/mol

C7NH16O2 molar mass = 7 x C atomic mass + N atomic mass + ( 16 x H atomic mass) + ( 2 x O atomic mass)

           = ( 7 x 12) + 14.0067 + ( 16 x 1.0078) + ( 2 x15.999)

    = 146.13 g/mol