A pure solid and a pure liquid are definitely a single phase because they are so united, or homogeneous. This leads to a homogeneous mixture also being a single phase.
The option that cannot be considered a single phase is D. a heterogeneous mixture.
Answer:
- 0.63 V.
Explanation:
From the question , the reaction is as follows -
Zn²⁺ (aq) + Pb (s) → Zn (s) + Pb²⁺ (aq)
From the above reaction ,
Zn²⁺ is reduced to Zn , as the oxidation state changes from +2 to 0
and ,
Pb is oxidized to Pb²⁺ , as the oxidation state changes from 0 to +2 .
In a cell , the process of oxidation takes place in the Anode , and reduction takes place in Cathode .
Hence , the half cell reaction taking place at anode and cathode is as follows -
Cathode reaction: Zn²⁺ (aq) + 2e⁻ → Zn (s) ; E⁰ Zn²⁺ /Zn = - 0.76 V.
Anode reaction: Pb (s) → Pb²⁺ (aq) + 2e⁻ ; E⁰ Pb²⁺ /Pb = - 0.13 V
The E⁰cell is calculated as the difference in the E⁰cathode and E⁰anode .
E⁰cell = E⁰cathode - E⁰anode = - 0.76 - (-0.13) = - 0.63 V.
Answer:
8.34 moles
Explanation:
We are given 8.34 moles.
We need to find moles: 8.34
Reaction on positive electrode (cathode):
PbSO₄₍s₎ + 2H₂O₍l₎ → 2e⁻ + PbO₂₍s₎ + 4H⁺₍aq₎ + SO₄²⁻₍aq₎.
s - solid.
l - liquid.
aq - dissolve in water.
PbSO4 is converted to Pb at one electrode (anode) and to PbO₂ at the other (cathode). Lead battery can be recharged, during recharging, an external source of energy is used.