Presentation on theme: "Polar Bears and Penguins Making Sense page 135. Unit 2 Investigation IV The ability of an atom to attract electrons shared between two atoms is called."— Presentation transcript:
Unit 2 Investigation IV The ability of an atom to attract electrons shared between two atoms is called electronegativity. – High electronegative atoms (polar bears) gain a - (partial negative) – Low electronegative atoms (penguins) gain a + (partial positive) Making Sense -133
Water Molecule: Oxygen attracts the shared electrons towards itself so it is partial negative. Hydrogen is less electronegative so the shared electrons are pulled away. It becomes partially positive. Unit 2 Investigation IV Direction of pull
– There is a crossed arrow to show the direction of the dipole in HCl. The crossed end of the arrow indicates the positive (+) end of the polar bond and the arrow points in the direction of the negative (-) end.
Nonpolar molecules They have symmetrical shapes like linear and tetrahedral and identical surrounding atoms. (Bonded electrons are being pulled but they are canceled out.
Unit 2 Investigation IV Polar molecules It is not symmetrical. There are different shapes.