Question

The simulation shows two types of molecules: a polar molecule and a non-polar molecule. Which one is the polar molecule? How can you tell? Assume that one molecule is HBr and another is Br2. Which one is which? Explain.

a) The polar molecule is HBr because it has a positive and negative end. Br2 is non-polar because it's symmetrical.
b) The polar molecule is Br2 because it has a positive and negative end. HBr is non-polar because it's symmetrical.
c) Both HBr and Br2 are polar molecules.
d) Both HBr and Br2 are non-polar molecules.

Answer 1

The polar molecule between HBr and Br2 is HBr, as it contains a polar covalent bond between hydrogen and bromine, which have different electronegativities. Br2 is non-polar due to the identical nature of the bromine atoms resulting in a symmetrical molecule.

Step-by-step explanation:

To determine which molecule is polar between HBr (hydrogen bromide) and Br2 (dibromine), we can look at the symmetry of the molecule and the electronegativity of the atoms involved. A polar molecule has a distribution of electric charge leading to one end being slightly positive and the other end being slightly negative, resulting in a molecule with a dipole moment. In diatomic molecules, polarity arises when the two atoms have different electronegativities. In the case of HBr, hydrogen and bromine have different electronegativities which results in a polar covalent bond and thus a polar molecule. Br2, however, is a molecule composed of two identical bromine atoms; therefore, it is non-polar due to its symmetrical nature and equal electronegativities of the bromine atoms.

The correct answer to the given question is option 'a': The polar molecule is HBr because it has a positive and negative end. Br2 is non-polar because it's symmetrical and the atoms have the same electronegativity.