A biological washing powder is effective at 40 °C but removes almost no stain at 90 °C. What is the best explanation?

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Question

A biological washing powder is effective at 40 °C but removes almost no stain at 90 °C. What is the best explanation?

Accepted Answer

The enzymes have been denatured and can no longer bind their substrate — Award 1 mark. High temperature changes the shape of the active site permanently, so cooling the wash afterwards does not restore activity.

Answer

Stains become chemically bonded to fabric above 50 °C

Answer

The enzymes dissolve completely at high temperature

Answer

The enzymes have been denatured and can no longer bind their substrate

Answer

The enzymes need light as well as warmth to work

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