A number of electrons, protons, and neutrons in chemical species A, B, C, and D is given below.
Element |
Electrons |
Protons |
Neutrons |
A |
2 |
3 |
4 |
B |
10 |
9 |
8 |
C |
8 |
8 |
8 |
D |
8 |
8 |
10 |
Now answer the following questions:
1. What is the mass number of A and B?
2. What is the atomic number of B?
3. Which two elements represent a pair of isotopes and why?
4. What is the valency of element C? Also, justify your answers.