Question

1. a closed flask of air (0.250l) contains 5.0 “puffs” of particles. the pressure probe on the flask reads 93 kpa. a student uses a syringe to add an additional 3.0 “puffs” of air through the stopper. find the new pressure inside the flask. particle diagram:

©modeling instruction - amta 2023 2 u2 ws 3 v3

Explanation:

Step1: Identify the formula

Use Avogadro's law in the form \(\frac{P_1}{n_1}=\frac{P_2}{n_2}\) (since \(V\) and \(T\) are constant).

Step2: Substitute the values

Given \(P_1 = 93\space kPa\), \(n_1=5.0\), \(n_2=(5.0 + 3.0)=8.0\).

$$P_2=\frac{P_1\times n_2}{n_1}$$

$$P_2=\frac{93\times8.0}{5.0}$$

$$P_2 = 148.8\space kPa$$

Answer:

\(149\space kPa\) (rounded to three significant figures)