He could be blindfolded and know which was his and which was his sister's. All he would need to do is pick them both up and if they were too big then pick them up one at a time. The lumber might make it harder to tell, but this is a question about physical properties.
So there is a change in mass which for the purpose of this question should be quite different. His sister's ought to be much lighter than his. He would find it easier to pick up.
I believe it would be a compound.
The answer is 2 electrons.
The electron configuration of calcium is 2:8:8:2
Calcium has two electrons in its outermost shell. These are its valence electrons and are the ones used in bonding with other elements. Valence electrons of an atom are those electrons that are in its outer energy shell or that are available for bonding.
Calcium is a metal. When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms forming ions. The resulting compound is known as an ionic compound.
For example, when calcium metal reacts with chlorine gas, calcium gives up its two valence electrons and Chlorine accepts them resulting in a new substance called calcium chloride in which the two elements have ended up forming ionic bonds.
Its a snake. snakes have lungs and a foot but no legs. its offspring are in eggs
