The standard temperature and pressure is 273 K and 1 atm. Since, pressure is not changed we can use Charle's law for the calculations.
Charle's law says "at a constant pressure, the volume of a fixed amount
of gas is directly proportional to its absolute temperature".
V α T
Where V is the volume and T is the temperature
in Kelvin of the gas. We can use this for two situations as,
V₁/T₁ = V₂/T₂
V₁ =
806 mL
T₁ =
26 ⁰C = 299 K
V₂ =
?
T₂ =
273 K
By applying the
formula,
(806 mL / 299 K) = (V₂ / 273 K)
V₂ = 735. 91 mL
Hence, the answer is "a".
