Answer:
The enthalpy of the second intermediate equation is altered by halving its value and changing the sign.
Explanation:
Let's examine both the first and second intermediate reactions alongside the overall equation concerning the examined process;
First reaction;
Ca (s) + CO₂ (g) + ½O₂ (g) → CaCO₃ (s) ΔH₁ = -812.8 kJ
Second reaction;
2Ca (s) + O₂ (g) → 2CaO (s) ΔH₂ = -1269 kJ
Thus, the overall reaction becomes;
CaO (s) + CO₂ (g) → CaCO₃ (s) ΔH =?
According to Hess's law, which states that the total heat change in a reaction is equal to the sum of the heat changes for each step, we cannot simply sum the enthalpies for this overall reaction. Instead, we obtain the overall enthalpy by halving the second intermediate reaction's enthalpy and changing its sign before adding, as illustrated below;
Enthalpy of Intermediate reaction 1 + ½(-Enthalpy of Intermediate reaction 2) = Enthalpy of Overall reaction
The formula for molality is

Given: A solution's molality equals 2.25 m
The weight of the solvent is 30 g, which is the same as 0.030 kg
Molecular weight of AlCl3 is 133.34 g/mol
Thus, we have the equation, 2.25 =

Therefore, the weight of the solute (g) becomes 9.00 g
Hence, <span>
9.00 g of AlCl3 is necessary for creating a 2.25m solution in 30.0 g of water</span>
Co2 is indeed the correct answer, my friend.
The unknown acid is identified as either butanoic acid or ascorbic acid. To ascertain the number of moles based on the given molarity, we utilize the following relationship: Molarity of NaOH solution = 0.570 M and Volume of solution = 39.55 mL. Utilizing the values in the provided equation, we derive the necessary data. The equation governing NaOH and monoprotic acid reactions indicates that one mole of NaOH reacts with one mole of HX, resulting in 0.0225 moles of the monoprotic acid. Conversely, in the case of NaOH and diprotic acid interactions, the stoichiometry is such that two moles of NaOH engage with one mole of diprotic acid. Consequently, we can calculate moles for butanoic acid with a mass of 2.002 g and a molar mass of 88 g/mol, leading us to the conclusion that both butanoic and ascorbic acids represent the unknown acid being neutralized.
Answer:
D) Mn + Ni2+ ⇒ Mn2+ + Ni
Explanation:
A spontaneous process can occur in a specific direction without requiring any energy input from external sources. Such reactions happen naturally. In these spontaneous processes, the entropy change is positive (ΔS), the enthalpy change is negative (ΔH), and most importantly, ΔG (the change in free energy) is negative.
To identify which reaction is spontaneous, we analyze the electrode potentials of the involved species. The species with a more negative reduction potential can displace the other from its aqueous solution. In this case, since the reduction potential for Mn^2+ is -1.19 V compared to nickel's -0.25 V, manganese will thus naturally displace Ni^2+ from solution as indicated in the solution above.