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प्रश्न
If pressure increases, the melting point of a substance ______.
विकल्प
does not change
decreases
increases
remains constant
उत्तर
If pressure increases, the melting point of a substance increases.
Explanation:
Most substances' melting points rise as pressure increases because the solid state is more compact than the liquid state. Higher pressure favors the solid phase, necessitating additional heat (higher temperature) to overcome this and cause melting. Ice is an exception to this rule, as its melting point decreases under pressure due to its unusual structure.
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