That's kind of a ponderous way to describe it, but your 'X' represents
the absolute temperature of the ideal gas.
Characteristic properties can be used to describe and identify the substances, while non-characteristic properties, although can be used to describe the substances, cannot be used to identify them.
Temperature, mass, color, shape and volume are examples of non-characteristic properties.
Density, boiling point, melting point, chemical reactivity are examples of characteristic properties.
List of the properties observed by the scientist:
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Property Type of property
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Volume: 5 ml non-characteristic
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Color: blue non-characteristic
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State: liquid characteristic
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density: 1.2 g/cm characteristic
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Reaction: reacts with CO2 characteristic
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