For which entalphy changes is the value of ΔH always negative? 1- combustion
2-hydration
3-solution

( the answer choices is a, b,c, d)
a) 1,2 & 3 are correct
b) 1 & 2 are correct
c) 2 & 3 are correct
d) 1 only is correct

What is the temperature of 0.750 mol of a gas stored in a 6,850 ml cylinder at 2.21 atm? . 2.95 k 5.24 k 138 k 246 k

650.j is the same amount of energy as? 2720cal1550cal650.cal2.72cal

Some liquids can be distilled, but only at temperatures that are so high that it is impractical, or so high the compound decomposes. explain why distillation such compounds at significantly less than atmospheric pressure (some degree of vacuum) would solve this problem.