<h3>
Answer:</h3>
5.2 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>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 6HCl + Fe₂O₃ → 2FeCl₃ + 3H₂O
[Given] 10.4 mol HCl
<u>Step 2: Identify Conversions</u>
[RxN] 6 mol HCl = 3 mol H₂O
<u>Step 3: Stoichiometry</u>
- Set up:

- Multiply/Divide:

I’m I’m pretty sure this is a combustion reaction, so that means the products would be CO2 + H2O.
<u>Answer:</u> The mass of sample A after given time is 99.05 g.
<u>Explanation:</u>
All the radioactive reactions follows first order kinetics.
The equation used to calculate half life for first order kinetics:

We are given:

Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = 84.2 s
= initial amount of the reactant = 250 g
[A] = amount left after decay process = ?
Putting values in above equation, we get:
![0.011s^{-1}=\frac{2.303}{84.2s}\log\frac{250}{[A]}](https://tex.z-dn.net/?f=0.011s%5E%7B-1%7D%3D%5Cfrac%7B2.303%7D%7B84.2s%7D%5Clog%5Cfrac%7B250%7D%7B%5BA%5D%7D)
![[A]=99.05g](https://tex.z-dn.net/?f=%5BA%5D%3D99.05g)
Hence, the mass of sample A after given time is 99.05 g.
It’s chlorine (Cl) having the atomic number 17
Answer: A. 1.5 g
Explanation:



According to stoichiometry:
1 mole of
requires = 3 moles of 
Thus 0.25 moles of
will require =
of 
Mass of
required =
The minimum amount of
in grams that would be required to completely react with this amount of
is 1.5 grams.