1.

A mixture of an acid anhydride (A) anda mono basic acid (B) on heating produces another mono basic acid (C) of equivalent weight 74 and m an anhydride (D). The acids and anhydrides remain in equilibrium. The anhydride (D) contains two identical fluoro alkyl groups. The acid (B) contains a trifluoro methyl group and has an equivalent weight of 128. Give structures of (A) to (D) with proper reasoning (Atomic weight of fluorine =19).

Answer» <html><body><p></p>Solution :`underset((A))((RCO)_2)O+2R'-underset((<a href="https://interviewquestions.tuteehub.com/tag/b-387190" style="font-weight:bold;" target="_blank" title="Click to know more about B">B</a>))(COOH)tounderset("<a href="https://interviewquestions.tuteehub.com/tag/mol-1100196" style="font-weight:bold;" target="_blank" title="Click to know more about MOL">MOL</a>.wt.<a href="https://interviewquestions.tuteehub.com/tag/74-334795" style="font-weight:bold;" target="_blank" title="Click to know more about 74">74</a>")underset((C))(2RCOOH)+underset((D))(R'CO)_2O` <br/> Mol. Wt. of `R-COOH=74,R+12+32+1=74,R=74-45=29(C_2H_5)` <br/> Thus, (C) is `CH_3CH_2COOH` and on the basis of above reaction, acid anhydride (A) is `(C_2H_5CO)_2O`.The acid anhydride (D) contains two identical fluoro alkyl groups. The acid (B) contians a trifluoro methyl group and has an equivalent weight of 128. Hence, mono basic acid (B) is `CF_3CH_2COOH` and so, acid anhydride (D) is `(CF_3CH_2CO)_2O`. <br/> Reactions: <br/> `underset((A))((CH_3CH_2CO)_2O)+underset("Eq.wt.=128")underset((B))(CF_3CH_2COOH)tounderset("Eq.wt.= 74")underset((C))(CH_3CH_2COOH)+underset((D))((CF_3CH_2CO)_2O)`.</body></html>


Discussion

No Comment Found

Related InterviewSolutions