Which of the following species behave both as a nucleophile and an electrophile?
(i) `CH_(3)C=N:` , (ii) `CH_(4)`
(iii) `H_(2)C=O` , (iv) `H_(2)`

Which out of the following is : ( a) the weakest acid (b) the strongest acid ? (i) C_(2)H_(5)OH (ii) CH_(3)COOH (iii) C_(6)H_(5)OH (iv) H_(2)O

Classify the following molecules I ions as nucleophiles or electrophiles : HS^(-), BF_(3), CH_(3) CH_(2) O^(-), (CH_3)_3 N, CI^(+), CH_3 C^(+) = O, H_(2) N^(-) :, NO_(2)^(+)

Which atoms in each of the following molecules remain in the same plane and why? (i) CH_(3)CH=CH_(2) (ii) C_(6)H_(5)C-=C CH_(3) (iii) CH_(3)CH=C=C=CHCH_(3) (iv) CH_(3)COCH_(2)CH_(3)

Which of the following were called permanent gases ? (i) H_(2) , (ii) O_(2) (iii) N_(2) , (iv) CH_(4)