The best description for the relationship between the products and the reactants in an exothermic reaction is C. The potential energy of the products is less than the potential energy of the reactants.
"The other halogens are not as electronegative and so other hydrogen halides cannot form hydrogen bonds between molecules. Only London Forces are formed. - Therefore more energy is required to break the intermolecular forces in HF than the other hydrogen halides and so it has a higher boiling point."
not a hack link, just stating where i got your answer from! -
https://www.mytutor.co.uk/answers/17558/A-Level/Chemistry/Explain-the-unusually-high-boiling-point-of-HF/
the energy gained by proteins and carbohydrates differs from the energy gained by fats.
proteins and carbohydrates both give 4 kcal per gram
fats give 9 kcal per gram
mass of proteins - 2 g
energy given by proteins - 2 g x 4 kcal/g = 8 cal
mass of carbohydrates - 20 g
energy given by carbohydrates - 20 g x 4 kcal/g = 80 cal
mass of fat - 1 g
energy given by fat - 1 g x 9 kcal/g = 9 cal
total energy = 8 + 80 + 9 = 97 kcal
energy = 97 kcal
Solar winds. Plasma particles from the sun affect earth's atmosphere and cause magnetic interferance.
