Without doing any calculations, predict the sign of H for
each of the following reactions:
(a) NaCl1s2¡Na+ 1g2 + Cl-1g2

Question

Accepted Answer

well everyone in this video, we're trying to find the sign of the end will be changed for this specific reaction right here. So taking a look at the reaction, we have a compound. So the CS compound that's being separated into the sea A two plus carry on and S two minus an ion. So again we have R. C A two plus and it's going to be our cat ion And then we have our S. 2 - which is going to be our an ion. And of course the difference between the Koran and the N ion is that it's different charges. So there let's say we just put uh specifically churched and in order to separate these ions or separate into these ions, it requires energy meaning that input of energy is required. So we'll have needs energy to be pulled apart or broken apart. Okay, so in scientific terms for the separation of these islands, it just means we have a endo thermic reaction. So we can symbolize this as a So let's say this is and oh thermic sobel symbolizes as a positive delta H. So whenever we have a positive delta H will be endo thermic and we have a negative delta HDL exo thermic in this case because we're requiring energy to separate these islands. We have an endo thermic reaction mean that the charge or the sign of the entropy change of reaction is going to be positive. So this is going to be our final answer for this problem

Without doing any calculations, predict the sign of H for each of the following reactions: (a) NaCl1s2¡Na+ 1g2 + Cl-1g2

Verified Solution

Key Concepts

Enthalpy Change (ΔH)

Lattice Energy

Thermodynamic Favorability