Answer:
The charge of the purple circles should be positive because they represent the nuclei.
Explanation:
45 is the atomic mass of the atom. And the name is Scandium
Answer:

Explanation:
Hello,
In this case, since hydrochloric acid and barium hydroxide are in a 2:1 molar ratio, for the neutralization, the following moles equality must be obeyed:

In such a way, in terms of molarities and volumes, we can compute the required volume of hydrochloric acid as shown below:

Besr regards.