Electronegativity Flashcards
How do you know if a molecule is non-polar?
It must meet both two criteria not only one!!
1)the central atom has no lone pairs of it does it must be a square planer( 4 atoms ,2 lone pairs) or linear (2 atoms ,3/4 lone pairs )
2)all atoms around the central atom are the same.
What is the definition of electronegativity?
The ability of an Atome to attract the electrons in the covalent towards itself.
Delta +. Delta-
What does the Paulin scale suggest ?
How powerful each element is at attracting electrons towards itself in a covalent bond.electonegativity number
Hydrogen=2.1
Carbon=2.5
Chlorine=3.0
Nitrogen= 3.0
Oxygen=3.5
Fluorine=4.0
What are 3 factors affecting electronegativity
No.of protons=the more protons the stronger the force of attraction
Atomic Radius=the closer the bonding pair to the nucleus the stronger the force of attraction
Shielding=more inner shells between the the bonding pair and nucleus the weaker the force of attraction.
What are two trends of electronegativity in the periodic table?
Down the group =atoms get bigger ,more shielding so weaker attraction between bonding pair and nucleus
Across=means nucleus charge increases so the force between the nucleus and the outermost shell increases so the shells get closer together so it becomes smaller,more protons so electronegativity increases
1)What is a net dipole moment?
When is it used?
2)what is the relationship between EN and dipole moment?
3)what is it used for ?
4)examples
1)only occur in polar bonds It is the measure of the strength and direction of the polarity of the bond .
2)The bigger the difference in EN the bigger the bond dipole moment.
3)to find the polar nature of the bond.
4)Molecules with zero dipole moment are non-polar in nature, while molecules with dipole moment are said to be polar in nature.
What is a dipole?
Molecule whose ends have opposite charge
If the bonding atoms have different elements the one with higher no of electronegativity will attract the bonding electrons more.
Why is there symmetrical density in non-polar molecules?
In covalent bond between identical atoms each nucleus attracts the electrons equally as EN is the same
So there is a SYMMETRICAL DENSITY
ITS IS NON-POLAR
Which molecules have polar or non polar bonds?
Non-Polar molecules =can have non-polar and polar bonds however the dipoles cancel out so it becomes non-polar as molecule is symmetrical
Polar molecules = have polar bonds
