an air sample of 210 ml was measured at 55 Celsius at what temperature in Celsius will the volume be 73 ml?

-159°C will be the T° for 73 mL

Explanation:

When the pressure and moles are constant for two situations on a gas, the volume changes according to the temperature change.

If the temperature rises → volume increases

If the temperature decreases → volume decreases

When we talk about temperature, we must use Absolute T°

T° K = T°C + 273

V₁ / t ₁ = V₂ / T₂

55°C + 273 = 328 K

210 mL / 328 K = 73mL / T₂

T₂ = 73 mL. 328K / 210 mL → 114 K → 114 K - 273 = - 159°C