2. Answer the following questions .

D. Calculate the molecular mass of the following in u.

a. NH_{3} b. CH_{3 }COOH c. C_{2}H_{5}OH

A) NH_{3 }

_{molecular mass of }NH_{3 =(1\(\times atomic \space mass \space of \space N\)} ) +\((3\times\) atomic mass of H)

\(=(1\times14 u)+(3\times 1u)\)

=17 u

B) CH_{3 }COOH

molecular mass of CH_{3 }COOH =\((2\times atomic \space mass \space of \space C)\) + (2\(\times atomic \space mass \space of \space O\) ) +(4\(\times atomic \space mass \space of \space H\) )

=\((2\times 12u)+(2\times 16u)+(4\times 1u)\)

=60 u

C) C_{2}H_{5}OH

molecular mass of C_{2}H_{5}OH = \((2\times atomic \space mass \space of \space C)+(6\times atomic \space mass \space of \space H)+(1\times atomic \space mass \space of \space O)\)

=\((2\times 12u)+(6\times 1u)+(1\times 16u)\)

=46 u