Exam specific answers (bonding) Flashcards
1
Q
explain how hydrogen bonding arises in a H-F molecule? (3)
A
there is a large difference in electronegativity between the H and F atom
this creates a permanent dipole-dipole/polar bond
an attraction is formed between the partially positive H atom and the lone pair on the F atom
2
Q
explain why the O-H bond in a methanol molecule is polar? (1)
A
oxygen is more electronegative than hydrogen
3
Q
give one reason why ice is less dense than water? (1)
A
hydrogen bonding in ice causes molecules to be held further apart than in liquid water
4
Q
the C-Br bond is polar - explain why CBr4 is not a polar molecule. (2)
A
the molecule has a tetrahedral shape, meaning the dipoles cancel out
