What is the primary reason that atomic radius decreases as you move from left to right across the periodic table even through the number of electrons is increasing?

As you move across a period the electrons are being added to the same shell. But, protons are being added as well. This makes the nucleus more positively charged and, increasing protons has a greater effect than electrons. So, there is a greater nuclear attraction and, because the electrons are being added to the same shell that shell gets pulled in more. This causes a decrease in atomic radius.

Explanation:

the answer is a. co2, this would be colder than the : )

explanation: