The overall chemical equation is c(s) + h2o(g) to co(g) +h2(g) . to calculate the final enthalpy of the overall chemical equation, which step must occur?
reverse the first equation, and change the sign of the enthalpy. then, add.
reverse the second equation, and change the sign of the enthalpy. then, add.
multiply the first equation by three, and triple the enthalpy. then, add.
divide the third equation by two, and double the enthalpy. then, add.

one negative thing it that it can kill water animals. another negative thing is it can cause the destruction of ecosystem. one way water pollution can be reduced is to conserve energy.

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.