<h3>
Answer:</h3>
121 mol CH₄
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Organic</u>
- Writing chemical compounds
- Writing organic structures
- Prefixes
- Alkanes, Alkenes, Alkynes
<u>Atomic Structure</u>
- Using Dimensional Analysis
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
7.31 × 10²⁵ molecules CH₄
<u>Step 2: Identify Conversions</u>
Avogadro's Number
<u>Step 3: Convert</u>
<u />
<u />
<u />
<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 3 sig figs.</em>
121.388 mol CH₄ ≈ 121 mol CH₄
Answer:
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time is 0.82 atm.
Explanation:
Initially
3.0 atm 0
At equilibrium
(3.0-2p) p
Equilibrium partial pressure of 
p = 0.45 atm
The value of equilibrium constant wil be given by :
After addition of 1.5 atm of nitrogen dioxide gas equilibrium reestablishes it self :
After adding 1.5 atm of 
:
(2.1+1.5) atm 0.45 atm
At second equilibrium:'
(3.6-2P) (0.45+P)
The expression of equilibrium can be written as:
Solving for P:
P = 0.37 atm
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time:
= (0.45+P) atm = (0.45 + 0.37 )atm = 0.82 atm
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time is 0.82 atm.
A scientific theory is a well tested explanation of a natural phenomenon.
