The mass would be 28. The mass of an atom equals the number of neutrons and protons added together. In this case, they do not say the protons. But we must use our inside knowledge to know that the number of protons equals the number of electrons. Thus, your number of protons would be 13
Your final answer is that you will need 52.9mL of the 8.20 M of LiCl
it will expand as water moves into it.
Answer:
Beryllium has an electronic configuration of 1s2 2s2 in its natural state. When in an ion state of Be2+ it loses the electrons in a 2s shell and has a configuration of 1s2. This means that Be2+ has 2 electrons.