The two are potassium and rubidium. Why? Na is an alkali metal. As you go down the metals become more reactive.
Calcium has 20 protons. Why? The atomic # is 20 (the one at the top).
It has 20 neutrons. Why? The atomic mass (the number on the bottom) is ~40, ignoring electron mass. 40- 20 protons = 20 neutrons.
It has 20 electrons.
Why? The # of protons and electrons is the same. Ions aren't on the periodic table.
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The nervous system coordinates it's actions by sending signals throughout the body
Answer: low pollution
Explanation:
The environmental effects of nuclear power is light compared to others
It would be best to use an MRI to check for any torn ligaments.
Hope this helps :)
Stored energy. Also this should have been listed under physics lol
