What is the effect of increasing temperature on a reaction with a negative ΔH an
Practice Questions
Q1
What is the effect of increasing temperature on a reaction with a negative ΔH and positive ΔS?
It makes ΔG more negative.
It makes ΔG less negative.
It has no effect on ΔG.
It makes ΔG positive.
Questions & Step-by-Step Solutions
What is the effect of increasing temperature on a reaction with a negative ΔH and positive ΔS?
Step 1: Understand the terms ΔH and ΔS. ΔH is the change in enthalpy (heat content) of the reaction, and ΔS is the change in entropy (disorder) of the system.
Step 2: Recognize that a negative ΔH means the reaction releases heat, making it exothermic.
Step 3: A positive ΔS indicates that the disorder of the system increases, which is favorable for spontaneity.
Step 4: Recall the Gibbs free energy equation: ΔG = ΔH - TΔS, where T is the temperature in Kelvin.
Step 5: Note that as temperature (T) increases, the term TΔS becomes larger because ΔS is positive.
Step 6: Since ΔH is negative, increasing T will make the negative TΔS term larger in magnitude, which makes ΔG more negative overall.
Step 7: A more negative ΔG means the reaction is more spontaneous, meaning it is more likely to occur.
