Question

how much hydrogen gas is necessary to exert a pressure of 1.4 ATM at 430k if occupying a volume of 15.1 l

Answer 1

Answer:

0.60 mol H₂

General Formula and Concepts:

Chemistry - Gas Laws

Ideal Gas Law: PV = nRT

• P is pressure
• V is volume in Liters
• n is number of moles
• R is the gas constant $0.0821 \frac{L \cdot atm}{mol \cdot K}$
• T is temperature in Kelvins

Explanation:

Step 1: Define Variables

P = 1.4 atm

T = 430 K

R = 0.0821 (L · atm)/(mol · K)

V = 15.1 L

n = unknown

Step 2: Solve for n

1. Substitute:                    $(1.4 \ atm)(15.1 \ L)=n(0.0821 \ \frac{L \cdot atm}{mol \cdot K})(430 \ K)$
2. Isolate n:                       $\frac{(1.4 \ atm)(15.1 \ L)}{(0.0821 \ \frac{L \cdot atm}{mol \cdot K})(430 \ K) }=n$
3. Multiply:                        $\frac{21.14 \ L \cdot atm}{35.303\ \frac{L \cdot atm}{mol} }=n$
4. Divide:                          $0.598816 \ mol =n_{H_2}$
5. Rewrite:                        $n_{H_2} = 0.598816 \ mol$

Step 3: Check

We are given 2 sig figs as our lowest. Follow sig fig rules and round.

0.598816 mol H₂ ≈ 0.60 mol H₂