Answer:
• Chemical properties can only be observed during a chemical reaction:
Chemical properties can only be established by changing a substance's chemical identity, and chemical properties are different from physical properties, which can be observed by viewing or touching a sample. The internal qualities of a substance must be altered to determine its chemical properties.
Examples:
Some common chemical properties are heat of combustion, enthalpy of formation, toxicity,
and flammability, each of which will be covered in this lesson.
• Rusting of iron is the chemical reaction not physical because:
The rusting of iron is a chemical change because it is two substances reacting together to make a
new substance. When iron rusts, iron molecules react with oxygen molecules to make a compound
called iron oxide. Rusting would only be a physical change if iron molecules remained pure iron
throughout the process.
The equation for this reaction is: 4Fe+ 3O2 → 2Fe2O
• Melting and boiling points are physical properties:
Yes melting and boiling points are the physical properties.
Physical properties can be observed or measured without changing the composition of matter. Physical properties are used to observe and describe matter.
Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others.
• Mass and volume are chemical properties:
No mass and volume are the extensive physical properties of matter
All properties of matter are either physical or chemical properties and physical properties are either intensive or extensive.
Extensive properties, such as mass and volume, depend on the amount of matter being measured.
Intensive properties, such as density and color, do not depend on the amount of the substance present.
Physical properties can be measured without changing a substance’s chemical identity.
• Various components of a mixture do not combine chemically:
When various components of a mixture do not combine chemically it is a Combination of substances in which individual components do not combine chemically but retain their individual properties. Mixture in which one or more substances are distributed evenly in another substance.
When various components combine chemically then form chemical compounds that are often divided into two categories. Metals often react with nonmetals to form ionic compounds. These compounds are composed of positive and negative ions formed by adding or subtracting electrons from neutral atoms and molecules
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