Calculate the standard enthalpy change for the reaction at 25 ∘ c. standard enthalpy of formation values can be found in this list of thermodynamic properties. c3h8(g)+ 5o2(g) ⟶ 3co2(g)+ 4h2o(g)

How do forces between particles in gases compare to forces in the other states of matter? o a. the forces in gases are stronger than forces in solids but weaker than forces in liquids. o b. the forces in gases are weaker than forces in solids but stronger than forces in liquids. o c. the forces in gases are weaker than forces in solids and liquids. o d. the forces in gases are stronger than forces in solids and liquids. submit

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.