I need help with a chem question....dealing with polarity and electronegativity..please help me?

Question

Name each molecule: NH2Cl, Cl2O, AsH5, AlH3, CCl2F2, O3(ozone). Which of these molecules are polar? For the polar molecules, label the electronegativity of each atom and show where the partial charges reside. Thanks so much!

Answer 1

The 1st, 2nd and 5th are polar. You have to work out how many electrons are on the central atom, and add one per covalent bond formed, and then work out whether there are any lone pairs. If there are, the molecule is likely to be polar, with the partial negative charge on the most electronegative atom.