AP Chem Semester 1 (U 1-5)

Front

What is the relationship between the mass of a gas and the number of molecules it contains at constant temperature and pressure?

Back

At constant temperature and pressure, the number of molecules of a gas is directly proportional to its mass. This is described by the ideal gas law and Avogadro's principle.

Front

Define lattice energy in the context of ionic compounds.

Back

Lattice energy is the amount of energy released when one mole of an ionic solid is formed from its gaseous ions. It is a measure of the strength of the forces between the ions in an ionic solid.

Front

What is the best laboratory glassware for preparing precise volumes of solutions?

Back

A volumetric flask is the best choice for preparing precise volumes of solutions due to its accuracy in measuring specific volumes.

Front

What role does a catalyst play in a chemical reaction?

Back

A catalyst increases the rate of a chemical reaction without being consumed in the process. It provides an alternative pathway with a lower activation energy.

Front

How does the polarity of a solvent affect the separation of dyes in chromatography?

Back

The polarity of a solvent affects the interaction between the dyes and the stationary phase. A less polar solvent will generally result in slower movement of polar dyes through the column.

Front

What is the ideal gas law equation?

Back

The ideal gas law is represented by the equation PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature in Kelvin.

Front

Explain Avogadro's principle.

Back

Avogadro's principle states that equal volumes of gases, at the same temperature and pressure, contain an equal number of molecules.

Front

What is the significance of the average kinetic energy of gas molecules?

Back

The average kinetic energy of gas molecules is directly proportional to the temperature of the gas. Higher temperatures correspond to higher average kinetic energy.

Front

Define the term 'reactant' in a chemical reaction.

Back

A reactant is a substance that undergoes a change during a chemical reaction, combining with other reactants to form products.

Front

What is the difference between a reactant and an intermediate in a reaction mechanism?

Back

A reactant is a starting material in a reaction, while an intermediate is a transient species formed during the reaction that is not a final product.