When a compound is dissolved in hot ethanol during a recrystallization, what is changing on a molecular level?

a. the compound is melting into the hot solvent.
b. the molecular weight of the compound is decreasing.
c. the covalent bonds are breaking.
d. the intermolecular forces within the solvent.
e. the intermolecular forces between the solute and solvent

What type of energy do chemical bonds have? what type of energy is it converted to during chemical reactions? question 15 options: chemical bonds have kinetic energy, which is converted to potential energy during chemical reactions. chemical bonds have electric energy, which is converted to potential energy during chemical reactions. chemical bonds have heat energy, which is converted to kinetic energy during chemical reactions. chemical bonds have potential energy, which is converted to heat energy during chemical reactions.

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.