Which element is a solid at 1400K? You need to use the Chemistry Reference Tables (Table S) to answer the question. Note: Think about the phase changes that happens at the melting point and boiling point of a substance and which phase will exist above and below the melting and boiling points. Ag
Al
Ca
Ni

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.