PDF chapter test TRY NOW
Fill in the blanks:
| atomic numbers | periods | seven | groups |
| first period | \(118\) | seven and eighteen | rows and columns |
| eighteen | two | hydrogen and helium | One and two |
| atomic masses | second period | three | hydrogen and oxygen |
1. The modern periodic table based on the elements were arranged in the increasing order of their __________.
2. The modern periodic table of __________ elements discovered so far.
3. The modern periodic table has __________ groups.
Register for free to see more content