<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>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 2Al₂O₃ → 4Al + 3O₂
[Given] 20 mol Al₂O₃
<u>Step 2: Identify Conversions</u>
[RxN] 2 mol Al₂O₃ → 4 mol Al
<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 1 sig fig.</em>
Since our final answer already has 1 sig fig, there is no need to round.
Answer: The coefficient is 3.645
The exponent is 1
There are 4 significant digits
The rightmost significant figure is 5
Explanation:
Scientific notation is defined as the representation of expressing the numbers that are too big or too small and are represented in the decimal form with one digit before the decimal point times 10 raise to the power.
For example : 5000 is written as 
According to avogadro's law, 1 mole of every gas contains avogadro's number
of particles, occupy 22.4 L at STP and weighs equal to its molecular mass.
131.29 g of Xe occupy = 22.4 L at STP.
Thus 213.62 g of
occupy =
at STP.
Scientific notation = 
The coefficient is 3.645
The exponent is 1
There are 4 significant digits
The rightmost significant figure is 5
The one that is being described above is what we call SCIENTIFIC LAW. Scientific law is what explains of what will happen every time in a certain situation. This is also different from scientific theory since scientific theory only gives an explanation to a group of happenings and this can still be modified. Hope this helps.
Nucleotide bases bonded to a sugar phosphate backbone make up nucleic acids such as DNA (deoxyribonucleic acid) and RNA (<span>ribonucleic acid)</span>. Nucleotides have three major parts: sugars, phosphates, and a nitrogenous base. DNA uses four nitrogenous bases: Adenine, Guanine, Cytosine, and Thymine. RNA uses the same bases except for Thymine, which is replaced by Uracil.
The properties of compounds are different, and in some cases very different, from those of the elements that compose them. This is because elements combine in compounds to become completely different substances with unique properties.
Compounds contain atoms of different elements chemically bonded in fixed ratios. An element is a pure chemical substance made up of atoms of the same kind. Compounds contain different elements in fixed ratios, arranged in a defined way by chemical bonds.
This is caused by different base properties where each element has a different number. Due to the number of electrons and differences in shell and valence electrons, different elements bond differently to certain other elements.
Compounds:
is composed of atoms of two or more different elements bonded together, and
can be broken down into simpler types of matter (elements) by chemical (rather than physical) means. from its components, and.
always contains the same proportions of atomic components.
Learn more about elements combine here;
brainly.com/question/6258301
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