<h3>
Answer:</h3>

<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>Atomic Structure</u>
<u>Stoichiometry</u>
- Using Dimensional Analysis
- Analyzing Reactions RxN
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 2C + O₂ → 2CO₂
[Given] 0.25 moles O₂
[Solve] moles CO₂
<u>Step 2: Identify Conversions</u>
[RxN] 1 mol O₂ → 2 mol CO₂
<u>Step 3: Stoichiometry</u>
- [DA] Set up:

- [DA] Multiply/Divide [Cancel out units]:

Answer:
Because only regular-shaped objects have a consistent length, width, height, and shape.
Explanation:
Because only regular-shaped objects have a consistent length, width, height, and shape. When dealing with an object composed of differing shapes, your must calculate each portion separately and then add them.
Answer: Option (B) is the correct answer.
Explanation:
Surface tension is defined as the attractive forces experienced by the surface molecules of a liquid by the molecules present beneath the surface layer of the liquid.
And, viscosity is defined as the ability of a liquid to resist its flow. When a substance has high viscosity then it is known as a viscous substance.
Since, it is given that viscosity of liquid B is more than liquid A. Therefore, liquid B has more resistive force on its surface as compared to liquid A. As a result, time taken by liquid B is more than time taken by liquid A.
Also, Surface tension = 
Surface tension of liquid B is more than liquid A. Therefore,
.
Thus, we can conclude that tA will be less than tB.
NO3- will affect the pH of a solution. The ion will decrease the pH of a neutral solution. No3- ion is a conjugate base of a strong acid, therefore, if it added to a neutral solution of pH 7, it will change the pH of the solution by decreasing the pH, that is, the solution will become acidic in nature.
Answer:
See explanation
Explanation:
According to Hund's rule, electrons must occur singly first before pairing takes place.
If I want to fill six electrons into orbitals, the filling of electrons will be as follows;
1s2 2s2 2p2.
The first four electrons are filled into the 1s and 2s levels having only one orbital each. The fifth and sixth electrons are filled into 2p orbitals. The 2p level have three degenerate orbitals. The two electrons are singly filled into each of the degenerate orbitals in accordance to Hund's rule.