12 x 10^23 atoms, i hope this helps
Atomic number.
The atomic number is what defines the element.
I would assume so.
Given

, we can simplify the fraction to

Both would obtain the same proportions, so I don't see why putting a half cup of sugar would make things any different.
Hope this is the answer you are looking for.
For #4 first find the molar mass(M) of copper then use that and the mass (m) n=m/M to find moles(n) using moles and the volumes find the concentration using c=n/V
Answer: incompressibility, rigidity, and density
Explanation: