Question

A sample of hydrogen gas at 1.50 atm and constant volume is heated from 0∘C to 150∘C. What will be the final pressure of the gas in atmospheres?
Use −273.15∘C for absolute zero.
Your answer should have three significant figures (round your answer to two decimal places).
Do not include units in your response.

Answer 1

Answer:

2.32

Explanation:

For the resolution of the problem one of the laws of Charles - Gay Lussac must be used, in which it is stated that if a certain amount of gas is kept at a constant volume (as in this case), its pressure will be directly proportional to its absolute temperature. Mathematically, it can be written as follows:

$\frac{P}{T} = Constant$ ⇒to constant V

In the case of the statement, that we have an initial system (P₁ and T₁) and an final system (P₂ and T₂), the equation can be written:

$\frac{P1}{T1} = \frac{P2}{T2}$

It can be rearranged to clear P₂ which is what needs to be calculated, then:

$P2=\frac{P1 . T2}{T1}$

It would only be necessary to convert the temperature units from ° C to K, to have the absolute temperature values. If T (K) = t (° C) + 273.15, then:

T₁ = 0 + 273.15 = 273.15 K

T₂ = 150 + 273.15 = 423.15 K

Now, you can replace the values ​​to the equation and calculate P₂

$P2 = \frac{1.50 atm . 423.15K}{273.15 K} = 2.3237atm$ ≅ 2.32 atm

As the statement requests the result with three significant figures and no units, the answer is that the final pressure is 2.32