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Question
Answer the following in one or two sentences.
State whether ΔS is positive, negative or zero for the reaction 2H(g) → H2(g). Explain.
Solution
ΔS is negative. Two moles of gaseous H atoms are converted into 1 mole of H2 gas. Thus, a disorder of the system decreases, and hence, entropy decreases, or ∆S is negative.
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