Entropy and Enthalpy Flashcards

Flashcards covering the concepts of entropy and enthalpy as described in the lecture notes.

What is entropy?

A measure of the randomness or disorder of a system.

What direction do systems in nature tend to change?

Systems in nature tend to undergo changes toward lower energy (enthalpy) and higher entropy.

What is enthalpy?

Heat transferred between the system and surroundings, carried out under constant pressure; also called potential energy or heat of reaction.

How does the number of moles relate to entropy?

More moles equal more entropy; add the coefficients to determine which side has more entropy.

What are spontaneous reactions?

A reaction that will proceed without any outside energy. In general, spontaneous reactions are exothermic, where entropy increases.

properties of acids

• taste sour

• are electrolytes

• react with bases to form a salt and water

• produce H+ (hydrogen ion) H3O+ (hydronium ion) ions in water

• pH less that 7

properties of bases

• taste bitter, chalky

• are electrolytes

• feel soapy, slippery

• react with acids to form salts and water

• produce OH- (hydroxide ions)in water

• pH is greater than 7

• turns red litmus paper to blue “basic blue”