2. Which of these has 23 protons?
Scandium Titanium Vanadium Chromium None of these
3. Which of these can an element have a different number of?
Protons Neutrons Electrons All of these None of these
4. Which of these has a negligible mass?
Protons Neutrons Electrons Atoms None of these
5. How many electrons in boron-11?
11 5 6 10 None of these
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