An indicator signals the endpoint of a titration by changing color. An indicator is a weak acid or a weak base where the acid form and the basic form of the indicator are different colors. For example, when a strong acid is titrated with a strong base, the pH at the equivalence point is 7, so an indicator that changes color at a pH of 7 should be used. Average score 4.28 Points awarded for each statement follow that statement. Constant a is related to the attractive forces that exist between real molecules.
Constant b is related to the fact that real molecules do have volumes.
H 2 S is a polar molecule and, therefore, has stronger intermolecular forces. H 2 S has a larger value for b because an H 2 S molecule has a larger volume than H 2 has. The constant a correlates with the boiling point since a is related to the intermolecular forces, which must be overcome in the process of boiling a liquid. Valence electrons in the s and p sublevels of their atoms. There are more metals than nonmetals because filling d orbitals in a given energy level involves the atoms of ten element and filling the f orbitals involves the atoms of 14 elements.