If the valence electrons were removed, what would be the ion charge of the element?

na =

-1

+1

-3

+3

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

What element breaks down into yttrium-90?

(apex) when a cup of water is dropped, as the cup falls, the water in the cup falls out true or false?