The reaction below shows how the potential energy changes during a chemical reaction. What does the red arrow show?
Potential Energy
Reaction Progress
A. The change in enthalpy is negative, and the reaction is exothermic.
hegativ
B. The activation energy is positive, and the reaction is exothermic.
C. The activation energy is negative, and the reaction is endothermic.
D. The change in enthalpy is positive, and the reaction is
endothermic

Express the following number in scientific notation. 0.026890 =

Which explanation is true about what happens to a ray of light when it strikes a mirror? a. a light ray is transmitted toward a mirror at a certain angle. the light ray is then reflected by the mirror at an equal angle but in the opposite direction of the transmitted ray. b. an incident ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then reflected at an angle equal to the angle of incidence but on the opposite side of the perpendicular line. c. a reflecting ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then refracted at an angle equal to the angle of the reflecting ray and on the same side of the perpendicular line. d. an incident ray strikes a mirror at an angle with a line parallel to the mirror. the light ray is then transmitted at an angle equal to the angle of incidence but on the opposite side of the parallel line. you so much! : -d take the time to try and answer correctly.

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.