Which of the following statements describe physical properties and which describe chemical properties? (a) Iron has a tendency t
o rust. (b) Rainwater in industrialized regions tends to be acidic. (c) Hemoglobin molecules have a red color. (d) When a glass of water is left out in the sun, the water gradually disappears. (e) Carbon dioxide in air is converted to more complex molecules by plants during photosynthesis.
a) Iron has the tendency to undergo rusting -- this is a chemical property as it involves a reaction with water and air.
b) Precipitation in industrialized areas often has an acidic nature -- this is also a chemical property due to its interaction with bases or metals.
c) Hemoglobin is red in color -- this is a physical property since it doesn't entail any chemical reactions.
d) When water is left out in sunlight, it evaporates gradually -- this is a physical property because the process can easily be reversed, classifying it as a physical change.
e) During photosynthesis, plants convert carbon dioxide into more complex molecules -- this demonstrates a chemical property since it involves chemical reactions.
