1. In the development of the modern periodic table, what is the best way of arranging the elements in the periodic table?
A. Increasing atomic mass
B. Increasing atomic number
C. Decreasing atomic mass
D. Decreasing atomic number
_____2. What is the maximum number of electrons that the 3d sublevel may contain?
A. 2
B. 4
C. 10
D. 14
_____3. An element has an electronic configuration 1s2 2s2 3s2 3p6 4s2 3d10 4p3. In what period does it belong?
A. 2
B. 3
C. 4
D. 5
_____4. The element in number 3 belongs to group number _______.
A. 4
B. 5
C. 6
D. 7