The Beryllium (Be) atom has 4 protons, 4 electrons (2 valence e-​ ​), and 5 neutrons. It is on the 2nd period, so it has two electron shells

(diagram below)

1. has two electron shells, so draw two rings around the nucleus

2. has 4 electrons, and since the first shell always has two the second shell would have 2 as well (to add up to four). this makes sense, because the description says that Be has 2 valence electrons

3. Draw 4 protons inside the grey circle (the nucleus)

4. Draw 5 neutrons inside the grey circle too (the nucleus)

they don't have to be in any particular order, hope this helps!

hloride, what is the mass of calcium in

explanation:

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explanation: