Answer:
Technetium, Promethium, Astatine, Francium
Explanation:
Because it has a smaller atomic number. Elements are not lined up according to the higher average atomic mass, but rather according to the higher atomic number.
Answer:
3.43 * 10^23 atoms of zinc
Explanation:
According to Avogadro's law, one mole of a substance contains a certain number of atoms of the substance commonly referred to as the Avogadro's number.
We already know from Avogadro's law that;
1 mole of zinc contains 6.02 * 10^23 atoms of zinc
Therefore;
0.57 mole of zinc will contain 0.57 * 6.02 * 10^23/1
which gives us 3.43 * 10^23 atoms of zinc
Option A is the only answer here.
n the Bohr Model, the electron is treated as a particle in fixed orbits around the nucleus. In the Quantum Mechanical Model, the electron is treated mathematically as a wave. The electron has properties of both particles and waves.
The Bohr model was a one-dimensional model that used one quantum number to describe the distribution of electrons in the atom. The only information that was important was the size of the orbit, which was described by “n” the principle quantum number.
Schrodinger's model (Quantum Mechanical Model) allowed the electron to occupy three-dimensional space. It, therefore, required three coordinates, or three quantum numbers, to describe the distribution of electrons in the atom.