decreases by 2. increases by 1. decreases for gases. increases for metals.
I gave my students this multiple choice question: The Periodic Table is arranged in rows and columns. From left to right along a row, the atomic number in each column

Only one answer is correct among these 4 choices:
- decreases by 2.
- increases by 1.
- decreases for gases.
- increases for metals.

Could you tell me which one is correct?

increases by 1.