Answer to Question #297269 in Chemistry for Tunde

Question

a given mass of gas occupies a volume of 950cm³ at 420/c and 0.92*10⁵ pressure. calculate the volume of the gas at S. T. P

Answer 1

P₁ =  0.92×10⁵ N m^-2 = 0.92×10⁵ Pa = 92000 Pa

T₁ = 420 K

V₁ = 950 cm³

STP = Standard Temperature and Pressure (T = 273.15 K and P = 101325 Pa)

Therefore,

P₂ = 101325 Pa (at STP)

T₂ = 273.15 K (at STP)

V₂ = unknown (at STP)

Solution:

The Combined Gas Law can be used:

P₁V₁/T₁ = P₂V₂/T₂

Cross-multiply to clear the fractions:

P₁V₁T₂ = P₂V₂T₁

Divide to isolate V₂:

V₂ = (P₁V₁T₂) / (P₂T₁)

Plug in the numbers and solve for V₂:

V₂ = (92000 Pa × 950 cm³ × 273.15 K) / (101325 Pa × 420 K) = 560.98 cm³ = 561 cm³

V₂ = 561 cm³

Answer: The volume of the gas at STP is 561 cm³