The correct orders of increasing acidic strengths is   a) CH4 < NH3 < H2O <  HF                                                                                                                                                                               
                b)CH4 < H2O < NH3 < HF                                                                                                                                                                              
                c)HF < H2O < CH4 < NH3                                                                                                                                                                                   
                d) HF < CH4 < NH3 < H2O          Experts , Please give explanation to the answer with example and without providing any link.    

Dear student,
Correct answer is (a). CH4 < NH3 < H2O < HF.
Acidic strength increases as the electronegativity of central atom increases. Electronegativity is in the order C < N < O < F.
Or we can understand it in different way-
Acids are the one which losses H+ ions and will form its conjugate base. More stable a conjugate base of an acid more strong the acid is i.e. it easily losses its H+ ion to form stable conjugate base.
HF conjugate base (C.B.) is F- , H2O C.B. is OH- , NH3 C.B. is NH2- , CH4 C.B. is CH3-. Stability order of these C.B. are ​F- > OH> ​NH2> ​CH3- .

Regards

  • -1
What are you looking for?