Question

Identify the physical change in the following list:

a.Yarn is decomposed by a lighted cigarette
b.Yarn is knitted into a cape
c.Cotton can be converted to a new substance by the addition of nitric acid
d.Linen produces a black, charred substance when treated with sulfuric acid
e.Silk fibers can be digested by moths

Answer 1

The physical change from the provided list is 'Yarn is knitted into a cape', which alters the form of the yarn without changing its chemical composition.

Step-by-step explanation:

The student has asked to identify the physical change from a provided list of changes. Among the options listed, the only example that represents a physical change is 'Yarn is knitted into a cape'. This process involves changing the shape or form of the yarn, but it does not alter the chemical composition of the yarn itself.

When identifying whether a change is physical or chemical, it's crucial to understand the nature of these changes. Physical changes are changes to the form or appearance of a substance that don't alter its chemical structure, while chemical changes result in the formation of one or more new substances with different properties from the starting materials.

Here are examples of both types of changes for clarification:

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• Breaking a mirror is a physical change.
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• Copper metal melting is a physical change.
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• Iron nail corroding is a chemical change.
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• Condensation of steam is a physical change.
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• Burning of gasoline is a chemical change.