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Tarnishing of silver is caused by hydrogen sulfide and other sulfur containing compounds in the air reacting to the silver and resulting in a fine layer of silver sulfide. The other answers don't make sense
Answer:
308 moles of sodium
Explanation:
The balanced equation for the chemical reaction between sodium metal (Na) and water (H₂O) is the following:
2 Na(s) + 2 H₂O → 2 NaOH(aq) + H₂(g)
From the equation, we can see that 2 moles of Na react with 2 moles of H₂O to give 2 moles of NaOH and 1 mol of H₂ (hydrogen gas). So the stoichiometric mole ratio between Na and H₂ is: 2 mol Na/1 mol H₂. Thus, we multiply the mole ratio by the moles of H₂ to be produced to obtain the moles of Na required:
moles of Na required = 2 mol Na/1 mol H₂ x 154 moles H₂ = 308 moles Na
Therefore, 308 moles of sodium are needed to produce 154 moles of hydrogen gas.
Phosphorus, Chlorine. The IUPAC name is Phosphorus pentachloride
Answer:
Explanation:
Hello,
In this case, considering the reaction, we can compute the Gibbs free energy of reaction at each temperature, taking into account that the Gibbs free energy for the diatomic element is 0 kJ/mol:
Thus, at 2000 K:
And at 3000 K:
Next, since the relationship between the equilibrium constant and the Gibbs free energy of reaction is:
Thus, at each temperature we obtain:
In such a way, we can also conclude that at 2000 K reaction is unfavorable (K<1) and at 3000 K reaction is favorable (K>1).
Best regards.
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