Calcium
this is because calcium will lose will lose more electrons and is a group 2 metal, copper is a transition metal which is a lower position and more stable than calcium.
An atomic mass unit (symbolized AMU or amu) is defined as precisely 1/12 the mass of an atom of carbon-12. The carbon-12 (C-12) atom has six protons and six neutrons in its nucleus. In imprecise terms, one AMU is the average of the proton rest mass and the neutron rest mass.
Answer:
Explanation:
If an atom has 13 electrons then it belongs to p-block of periodic table.
s level can accommodate 2 electrons.
p level can accommodate 6 electrons.
13 means 1s2 2s2 2p6 3s2 3p1.
As you can see there totally 5 sub-shells.
Total number of shells are 3(1,2,3).
A should be the products and D should be the reactants. So D should be the answer.
