Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.

Remove Ads
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards




share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Chemistry 2.4

AS edexcel chemistry - bond polarity

QuestionAnswer
What is electronegativity? A measure of the tendency of an atom to draw a pair of electrons from a covalent bond towards itself.
What is electronegativity measured by? Pauling scale - arbitrary units. Fluorine is the most electronegative element, caesium is the least
Where are electrons positioned in a polar vs non polar bond? In a covalent bond between 2 atoms of same element, average position of e- is half way between atoms. In a covalent bond between 2 atoms of different electronegativities, localised around 1, polar, ionic character, distortion of e- cloud, partial charges
What is a dipole moment? a measure of net molecular polarity and charge separation - measures the polarity of a bond
What are the properties of polarising and polarisable atoms? Polarising - high charge density, high charge and small atomic radius. Polarisable - high charge, large atomic radius
Why is a symmetrical molecule with polar bonds non-polar? Dipoles cancel. A polar molecule must be asymmetrical with polar bonds
Why are polar molecules water soluble? The partial charges on the polar molecule are attracted to the partial charges on the dipolar water molecules
What is meant by the continuum of bonding? Covalent and ionic are two extremes. There can be ionic with covalent character caused by polarisation of anion, and covalent with ionic character caused by polar bonds
What are the trends in electronegativity? - metals are less electronegative than non metals - electronegativity increases across a period due to increasing charge density - electronegativity decreases down group due to decreasing charge density
Why don't noble gases have electronegativity values? They rarely form covalent bonds
How do you test for polar molecules? Run a stream of liquid from a burette next to a rod that has been rubbed with wool and charged with static electricity, polar moelcules are attracted to high charge of the rod and the jet of liquid is deflected
Created by: 11043