Q. 14.38 - An Introduction to General, Organic, and Biological Chemistry

Question

Write the balanced chemical equations for the (1) reaction of each of the following amines with water and (2) neutralization with HBr:

a. ethylmethylamine

b. propylamine

c. N-methylaniline

Step-by-Step Solution

Answer

a. $C{H}_{3}N{H}_2 + H_{2}O \to C{H}_{3}N{H}_3 + O{H}^{-}$ 

     $C{H}_{3}N{H}_{2 }+ HBr \to {\left[C{H}_{3}N{H}_3\right]}^{+} + B{r}^{-}$

b. $C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{2 }+ H_{2}O \to C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{3+}+ O{H}^{-}$

    $C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{2 }+ HBr \to {\left[C{H}_{3}C{H}_{2}C{H}_{2}N{H}_3\right]}^{+}+ B{r}^{-}$

C. N-methylaniline does not reacts with water or HBr

Part (a) Step 1 : Given Information

We have to write the balanced chemical eq of reaction of methylamine with water and neutralization reaction with HBr.

Part (a) Step 2 : Reactions

$C{H}_{3}N{H}_2 + H_{2}O \to C{H}_{3}N{H}_3 + O{H}^{-}$

$C{H}_{3}N{H}_{2 }+ HBr \to {\left[C{H}_{3}N{H}_3\right]}^{+} + B{r}^{-}$

Part (b) Step 1 ; Given Information

We have to write the balanced chemical eq of reaction of propylamine with water and neutralization reaction with HBr.

Part (b) Step 2 : Reactions

$C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{2 }+ HBr \to {\left[C{H}_{3}C{H}_{2}C{H}_{2}N{H}_3\right]}^{+}+ B{r}^{-}$$C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{2 }+ H_{2}O \to C{H}_{3}C{H}_{2}C{H}_{2}N{H}_{3+}+ O{H}^{-}$

Part(c) Step 1 : Given Information

We have to write the balanced chemical eq of reaction of N-methylaniline with water and neutralization reaction with HBr.

Part(c) Step 2 : Reaction

N-methyl aniline is insoluble in water , hence does not react with water . And moreover it does not react with HBr either