Li(s) (answer A)
Li is strongest reducing agent because of the lowest standard reduction potential. when something is oxidized, it reduces another substance, becoming a reducing.Hence Lithium is strongest reducing agent. Reducing agent is stronger when it has a more positive oxidation potential.
Answer:
The value of Kp at this temperature is 7.44*10⁻³
Explanation:
Chemical equilibrium is established when there are two opposite reactions that take place simultaneously at the same speed.
For the general chemical equation for a homogeneous gas phase system:
aA + bB ⇔ cC + dD
where a, b, c and d are the stoichiometric coefficients of compounds A, B, C and D, the equilibrium constant Kp is determined by the following expression:

Where Px is the partial pressure of each of the components once equilibrium has been reached and they are expressed in atmospheres. The equilibrium constant Kp depends solely on temperature and is dimensionless.
In the case of the reaction:
2 HI (g) ⇔ H₂ (g) + I₂ (g)
the equilibrium constant Kp is determined by the following expression:

The system comes to equilibrium at 425 °C, and
- PHI = 0.794 atm
- PH2 = 0.0685 atm
- PI2 = 0.0685 atm
Replacing:

Kp=7.44*10⁻³
<u><em>The value of Kp at this temperature is 7.44*10⁻³</em></u>
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