Which statement describes a chemical property of silicon?
a) silicon has a blue-gray color.
b) silicon is a brittle solid at 20.°c.
c) silicon melts at 1414°c.
d) silicon reacts with fluorine.

Option (d) is the correct answer.

Explanation:

Out of the given options, options (d) represents chemical property of silicon as it shows that silicon reacts with fluorine.

A physical property is the property which can be observed without any change in chemical composition of the substance or molecule.

For example, color, shape, density, molecular weight etc are all physical properties.

A chemical property is the property which can be observed by changing the chemical composition of the substance or molecule.

For example, reactivity, flammability, oxidation state etc are all chemical properties.

Options (a), (b), and (c) are all showing the physical properties of silicon. Only option (d) shows the chemical property.

Hence, it is the correct answer.