Missing information:
The reaction is 2O₃(g) --> 3O₂ (g) ΔH = -300 kJ/mol
Answer:
c
Explanation:
In the molecule of ozone, 3 oxygens are bonded, and, because each one needs to share two pairs of electrons, these 2 bonds are something between a simple and a double bond.
In the reaction of the transformation of the ozone to oxygen gas, these bonds are broken, and a double bond is formed between two oxygen atoms. The sum of the energy of the broken and the formation of the bond is the enthalpy variation of the reaction.
To break a bond, energy must be added to the system, so it's an endothermic reaction and energy is positive, so the formation is exothermic and the energy is negative. Because there're 2 ozone molecules, 4 bonds will be broken, and because there are 3 oxygen molecules, 3 bonds will be formed:
4*E - 3*500 = -300
4E = -300 + 1500
4E = 1200
E = 300 kJ/mol
So, each O3 bond has 300 kJ/mol as an average energy.
Carbon Dating would tell you the age of the charcoal
The attachments dont work, they say that they have been taken down or sum... ?
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.
5CO2 should be in the blank spot.
the reaction would be 7