What property is shared by $^{40}\text{Ca}$, $^{39}\text{K}$ and $^{23}\text{Na}$?
- ATheir atoms all have more neutrons than protons.
- BTheir ions all have eight electrons in their outer shell.
- CThey all sink when added to water.
- DThey are all deposited at the positive electrode when their molten chloride is electrolysed.