The <span>era that is know as the age of mammals is the </span><span>Mesozoic
period.
Answer: Letter D
Hope that helps. -UF aka Nadoa</span>
Answer:
I think it is B
Explanation:
because the others don't look right
Answer:
A)21
Explanation:
To know the difference between the number of electrons in the two atoms, we must first know the number of electrons in the atoms.
For Selenium, Se, we have 34 electrons. The element is in group 6 on the periodic table.
Aluminum on the other hand is in the Boron family with a total of 13 electrons.
The difference,( 34-13) electrons gives a total of 21 electrons
<h3>
Answer:</h3>
10.6 mol NO
<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>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 4NH₃ + 5O₂ → 4NO + 6H₂O
[Given] 13.2 mol O₂
<u>Step 2: Identify Conversions</u>
[RxN] 5 mol O₂ → 4 mol NO
<u>Step 3: Stoich</u>
- [DA] Set up:

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

<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 3 sig figs.</em>
10.56 mol NO ≈ 10.6 mol NO
Density = 968 g/cm³
mass = 250 g
Volume = ?
Therefore:
D = m / V
968 = 250 / V
V = 250 / 968 => 0.26 cm³
Answer C