An unidentified 600 g metal solidified by releasing 3660 J of hest. Calculate the hest or fusion for the unknown metal.

Which statement justifies that phosphine (ph3) is a polar molecule?

For which one of the following reactions is the value of δh° rxn equal to δh° f for the product? a. 2 h2 (g) + o2 (g) → 2 h2o (l) b. n2 (g) + o2 (g) → 2 no (g) c. 2 h2 (g) + o2 (g) → 2 h2o (g) d. h2o (l) + 1/2 o2 (g) → h2o2 (l) e. none of the above

100mg magnesium reacts with 20ml of 1.0m hcl