Chemistry Flashcard

Front

What term describes the heat content of a system?

Back

Enthalpy

Front

Calculate the volume of 2.35 mole He at 423 K and 1.00 atm if it occupies 57.9 L at 300 K and 1.00 atm.

Back

81.6 L

Front

What is the order of the reaction given the rate law: rate = k [IO₃⁻][I⁻]?

Back

2

Front

What is the wavelength of light associated with the electron transition frequency of 2.913 x 10^15 Hz in the hydrogen spectrum?

Back

103 nm

Front

What is the equilibrium constant (K_eq) for the decomposition of phosphorus pentachloride (PCl₅) to phosphorus trichloride (PCl₃) and chlorine gas (Cl₂) if the initial concentration of PCl₅ is 1.10 mol/L and the equilibrium concentration is 0.33 mol/L?

Back

K_eq = 0.33 / (1.10 - 0.33)² = 0.33 / 0.5776 = 0.572.

Front

Define entropy in the context of thermodynamics.

Back

Entropy is a measure of the disorder or randomness in a system.

Front

What is Gibbs free energy and its significance in chemical reactions?

Back

Gibbs free energy (G) indicates the spontaneity of a reaction; a negative change in G means the reaction is spontaneous.

Front

Explain the concept of molarity.

Back

Molarity is the number of moles of solute per liter of solution (mol/L).

Front

What is the ideal gas law equation?

Back

PV = nRT, where P is pressure, V is volume, n is number of moles, R is the ideal gas constant, and T is temperature.

Front

What is the difference between exothermic and endothermic reactions?

Back

Exothermic reactions release heat, while endothermic reactions absorb heat.