A sample of ideal gas is in a sealed container. The pressure of the gas is 435 torr , and the temperature is 3 ∘C . If the temperature changes to 77 ∘C with no change in volume or amount of gas, what is the new pressure, P2, of the gas inside the container?

P₂ = 552 Torr

Explanation:

From Gay-Lussac Law => Change in pressure of a confined gas at constant volume and mass is directly proportional to the change in temperature.

P ∝ T => P = k·T => k = P/T

for k₁ = k₂ => P₁/T₁ = P₂/T₂

P₁ = 435 Torr

T₁ = 3°C = 276K

P₂ = ?

T₂ = 77°C = 350K

P₂ = 435Torr( 350K/276K) = 552 Torr

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol