Answer:
I believe it's false because the atomic number is the number of protons in the nucleus of an atom.
Explanation:
(a) potassium oxide with water

According to reaction,1 mole of potassium oxide reacts with 1 mole of water to give 1 mole of potassium hydroxide.
(b) diphosphorus trioxide with water

According to reaction,1 mole of diphosphorus trioxide reacts with 2 moles of water to give 2 moles of phosphorus acid.
(c) chromium(III) oxide with dilute hydrochloric acid,

According to reaction,1 mole of chromium(III) oxide reacts with 6 moles of hydrochloric acid to give 2 moles of chromium(III) chloride and 3 moles of water.
(d) selenium dioxide with aqueous potassium hydroxide

According to reaction,1 mole of selenium dioxide reacts with 2 moles of potassium hydroxide to give 1 mole of potassium selenite and 1 mole of water.
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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