A) calculate the standard free-energy change at 25 ∘c for the following reaction:
mg(s)+fe2+(aq)→mg2+(aq)+fe(s)
express your answer to three significant figures and include the appropriate units.
δg∘ =−3.71×105 j

b) calculate the standard cell potential at 25 ∘c for the reaction
x(s)+2y+(aq)→x2+(aq)+2y(s)
where δh∘ = -629 kj and δs∘ = -263 j/k .
express your answer to three significant figures and include the appropriate units

A) ΔG° = -3,80x10⁵ kJ

B) E° = 2,85V

Explanation:

A) It is possible to answer this problem using the standard ΔG's of formation. For the reaction:

Mg(s) + Fe²⁺(aq) → Mg²⁺(aq) + Fe(s)

The ΔG° of reaction is:

ΔG° = ΔGFe(s) + ΔGMg²⁺(aq) - (ΔGFe²⁺(aq) + ΔGMg(s) (1)

Where:

ΔGFe(s): 0kJ

ΔGMg²⁺(aq): -458,8 kJ

ΔGFe²⁺(aq): -78,9 kJ

ΔGMg(s): 0kJ

Replacing in (1):

ΔG° = 0kJ -458,8kJ - (-78,9kJ + okJ)

ΔG° = -3,80x10² kJ ≡ -3,80x10⁵ kJ

B) For the reaction:

X(s) + 2Y⁺(aq) → X²⁺(aq) + 2Y(s)

ΔG° = ΔH° - (T×ΔS°)

ΔG° = -629000J  - (298,15K×-263J/K)

ΔG° = -550587J

As ΔG° = - n×F×E⁰

Where n are electrons involved in the reaction (2mol), F is faraday constant (96485 J/Vmol) And E° is the standard cell potential

Replacing:

-550587J = - 2mol×96485J/Vmol×E⁰

E° = 2,85V

I hope it helps!

a) the particles of the chair are strongly held together.

answer: any goods being imported from another country may be subject to issued by the federal government are tariffs

explanation:  

tariffs are a tax on anything that are imported from abroad. government use them to protect and boost their local industries and the thought is that they encourage consumers to buy local instead of importing and they will hope will protect jobs and economy in the country that implements them