AP Chemistry Fall Semester Exam Review

Front

What is the solubility rule for nonpolar covalent molecules in nonpolar solvents like hexane?

Back

Nonpolar covalent molecules tend to have high solubility in nonpolar solvents due to similar intermolecular forces.

Front

How do you determine the empirical formula of a compound?

Back

To find the empirical formula, divide the mass of each element by its molar mass, then simplify the ratio to the smallest whole numbers.

Front

What is an empirical formula?

Back

An empirical formula represents the simplest whole-number ratio of atoms of each element in a compound.

Front

Which has a higher polarity: CO or HF?

Back

HF is more polar than CO due to the significant difference in electronegativity between H and F.

Front

What is the significance of the PES (Photoelectron Spectroscopy) spectrum?

Back

The PES spectrum provides information about the energy levels of electrons in an atom, helping to identify the element.

Front

What is the relationship between molecular structure and polarity?

Back

Molecular structure, including shape and electronegativity differences, determines the overall polarity of a molecule.

Front

How do you identify compounds with the same empirical formula?

Back

Compounds with the same empirical formula have the same ratio of elements, even if their molecular formulas differ.

Front

What is the molecular formula of a compound with an empirical formula of CaCl2 and a molar mass of 110.98 g/mol?

Back

The molecular formula is CaCl2, as the empirical formula's molar mass (110.98 g/mol) matches the compound's molar mass.

Front

What is the difference between ionic and covalent compounds?

Back

Ionic compounds are formed by the transfer of electrons between metals and nonmetals, while covalent compounds involve the sharing of electrons between nonmetals.

Front

What factors affect the solubility of a substance?

Back

Factors include temperature, pressure, and the nature of the solute and solvent (polarity, molecular size).