In the modern periodic table, one can explain the number of elements in various periods based on how electrons are filled into various shells. The position of an element tells us about its chemical reactivity, valency, atomic size, metallic and non-metallic properties, etc. These change as we move across and up/down the periodic table.
1. The horizontal rows in a modern periodic table are called _________
a. Blocks
b. Columns
c. Periods
d. Lines
2. In going across a period (right to left), the atomic size of the atom ________
a. Increase
b. decrease
3. On moving from right to left, the number of valence electrons ________.
a. Increase
b. decrease
4. On moving down in a group, the metallic character _______.
a. Increase
b. decrease
5. The tendency to gain an electron ______ on moving down in a group.
a. Increase
b. decrease