Answer: decreases
Explanation:
Atomic radius in a period from left to right decreases due to increase in nuclear charge.
On moving from left to right, electrons are getting added in outer shell and no of protons also increased which results increase in nuclear charge. Increased nulcear charge holds the electrons tigthly hence electrons moves close to nucleus. So radius decreases.
The density : 1.96 g/L
<h3>Further explanation</h3>
Ideal gas Law
Pv=nRT
where
P = pressure, atm , N/m²
V = volume, liter
n = number of moles
R = gas constant = 0.082 l.atm / mol K (P= atm, v= liter),or 8,314 J/mol K (P=Pa or N/m², v= m³)
T = temperature, Kelvin
so for density,
MW CO₂ = 44 g/mol

Answer:
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma). A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide).
Explanation: