Answer:
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Explanation:
<h2>Problem 1. </h2>
<u>a) Data:</u>
- n₁ = 0.126 mol
- V₁ = 2.74 L
- n₂ = 0.126mol + 0.124mol
- V₂ = ?
- Conditions: constant temperature and pressure
<u>b) Physical principles:</u>
The volume occupied by a gas, when the temperature and pressure remain unchanged, is proportional to the number of moles of gas.
<u>c) Solution:</u>
Solve for V₂ , substitute and compute:
<h2>Problem 2.</h2>
<u>a) Data:</u>
- n₁ = 0.547mol
- V₁ = 295 mL
- V₂ = ?
- n₂ = 0.547mol + 0.342 mol
- Conditions: constant temperature and pressure
<u>b) Physical principles:</u>
The same as above: the volume occupied by a gas, when the temperature and pressure remain unchanged, is proportional to the number of moles of gas.
<u>c) Solution:</u>
Solve for V₂ , substitute and compute:
Answer:
-0.93 °C; 100.26 °C
Step-by-step explanation:
(a) Freezing point depression
The formula for the freezing point depression ΔT_f is
ΔT_f = iKf·b
i is the van’t Hoff factor: the number of moles of particles you get from a solute.
For sucrose,
Sucrose (s) ⟶ sucrose (aq)
1 mole sucrose ⟶ 1 mol particles i = 1
ΔT_f = 1 × 1.86 × 0.50
ΔT_f = 0.93 °C
T_f = T_f° - ΔT_f
T_f = 0.00 – 0.93
T_f = -0.93 °C
(b) Boiling point elevation
The formula for the boiling point elevation ΔTb is
ΔTb = iKb·b
ΔTb = 1 × 0.512 × 0.50
ΔTb = 0.256 °C
Tb = Tb° + ΔTb
Tb = 100.00 + 0.256
Tb = 100.26 °C
In the following redox reaction, the reducing agent is MnO2 (option D). Details about reducing agent can be found below.
<h3>What is a reducing agent?</h3>
A reducing agent in a redox reaction is any substance that reduces, or donates electrons to another, hence, it becomes oxidized.
According to this question, a redox reaction is given as follows: MnO2(s) + 4H+(aq) + 2Cl–(aq) = Mn2+(aq) + 2H2O(l) + Cl2(g)
As shown in the equation, MnO2 is oxidized into Mn2+, therefore, it is the reducing agent.
Learn more about reducing agent at: brainly.com/question/2890416
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The mercury inside the thermometer is a pure substance hope this helps :)
