Answer:
See explaination
Explanation:
Since X is more reactive than Y
=> X is oxidized to X2+ and Y2+ is reduced to Y
Overall cell reaction is:
X(s) + Y2+(aq) => X2+(aq) + Y(s)
please kindly see attachment for further solution.
<h3>
Answer:</h3>
9 mol H₂O
<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>
- Reading a Periodic Table
- Moles
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<u>Stoichiometry</u>
- Using Dimensional Analysis
- Analyzing reactions RxN
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 6H₂ + O₂ → 3H₂O
[Given] 18 mol H₂
[Solve] mol H₂O
<u>Step 2: Identify Conversions</u>
[RxN] 6 mol H₂ → 3 mol H₂O
<u>Step 3: Stoich</u>
- [DA] Set up conversion:

- [DA] Simplify:

- [DA] Divide [Cancel out units]:

Answer : The reagent present in excess and remains unreacted is, 
Solution : Given,
Moles of
= 3.00 mole
Moles of
= 2.00 mole
Excess reagent : It is defined as the reactants not completely used up in the reaction.
Limiting reagent : It is defined as the reactants completely used up in the reaction.
Now we have to calculate the limiting and excess reagent.
The balanced chemical reaction is,

From the balanced reaction we conclude that
As, 2 moles of
react with 1 mole of 
So, 3.00 moles of
react with
moles of 
From this we conclude that,
is an excess reagent because the given moles are greater than the required moles and
is a limiting reagent and it limits the formation of product.
Hence, the reagent present in excess and remains unreacted is, 
The element name is: Antimony
The chemical symbol: Sb
Atomic Mass: 121.75
Atomic Number: 51