Consider the chemical equations shown here. 2 equations. 1: 2 upper H subscript 2 (g) plus upper O subscript 2 (g) right arrow 2 upper H subscript 2 upper O (g). Delta H 1 equals negative 483.6 kilojoules divided by 2 equals negative 241.8 kilojoules per mole. 2: 3 upper O subscript 2 (g) right arrow 2 upper O subscript 3 (g). Delta H 2 equals 284.6 kilojoules divided by 2 equals 142.3 kilojoules per mole. What is the overall enthalpy of reaction for the equation shown below? 3 upper H subscript 2 (g) plus upper O subscript 3 (g) right arrow 3 upper H subscript 2 upper O (g).

What is the independent variable in this investigation? mass volume sample number substance density

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.

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.