Which statement is true about endothermic and exothermic reactions? (5 points) a
Kinetic energy is absorbed and converted to potential energy in an endothermic reaction.

b
Kinetic energy is absorbed and converted to potential energy in an exothermic reaction.

c
Energy is released in an endothermic reaction.

d
Energy is absorbed in an exothermic reaction.

List four observations that indicate that a chemical reaction may be taking place

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.

What is the pressure of 0.500 moles of carbon dioxide gas in a 2.5 l tank and at a temperature of 301 k? (r=0.0821 l·atm/mol·k) 3.08 atm 1.2 atm 0.23 atm 4.01 atm 4.94 atm