Effect of temperature on spontaneityस्वतःप्रवर्तिता पर ताप का प्रभाव

NCERT Table 5.4 · interactive diagram

Parts and their functions

• ΔH negative, ΔS positive (ΔH ऋणात्मक, ΔS धनात्मक) — Both terms make ΔG negative → spontaneous at every temperature (e.g. combustion).
• ΔH negative, ΔS negative (ΔH ऋणात्मक, ΔS ऋणात्मक) — Spontaneous only when |ΔH| > T|ΔS|, i.e. at low temperature (e.g. freezing of water below 0 °C).
• ΔH positive, ΔS positive (ΔH धनात्मक, ΔS धनात्मक) — Spontaneous only when TΔS > ΔH, i.e. at high temperature: T > ΔH/ΔS (e.g. melting of ice above 0 °C).
• ΔH positive, ΔS negative (ΔH धनात्मक, ΔS ऋणात्मक) — ΔG is always positive → never spontaneous; the reverse reaction is spontaneous.

Original diagram drawn by Simple Learning Hub, based on NCERT Table 5.4. Report a mistake