During an exothermic chemical reaction,
a. a system becomes warmer, and the chemical substances undergo a decrease in potential energy.
b. a system becomes warmer, and the chemical substances undergo an increase in potential energy.
c. a system becomes cooler, and the chemical substances undergo a decrease in potential energy.
d. a system becomes cooler, and the chemical substances undergo an increase in potential energy.
e. a system becomes warmer, and additional heat is gained from the surroundings.

Using the periodic table, complete the table to describe each atom. type in your answers

How many valence electrons are in atom of radon?

You are attempting to recrystallize a crude product mixture. you add the appropriate amount of hot solvent and are allowing the solution to slowly cool to room temperature. however, at room temperature no crystals have appeared, which of the following methods should be used to induce crystallization? choose all correct answers. a) place the flask in an ice bath. b) swirl the contents of the flask. c) add a small seed crystal of the desired product. d) scratch the inside of the glassware using a stir rod. it can be multiple choices