What are the only two liquids that violate the principle of greater density at temperatures near their freezing points?

Which best describes the activation energy of a chemical reaction? a. the combined energy of all the reactants b. the amount of energy required for a reaction to occur c. the difference in energy between products and reactants d. the potential energy stored in the bonds of reactants and products

At which temperature would a reaction with ah= -220 kj/mol and as=-0.05 kj/(mol-k) be spontaneous?

What sources of error may have contributed to the percent yield not being 100 percent? think about things that may have led to inaccurate measurements or where mass of the product could have been lost if this experiment was conducted in a physical laboratory.