Which of the following geological changes are physical changes and which are chemical changes?
a)formation of a limestone cave
b)creation of a canyon by a river
c)wearing of rocks by wave action
d)destruction of lakes by acid rain
e)heaving of the ground by ice formation
a = chemical
b = chemical
c = chemical
d = chemical
e = physical
Please correct any mistake of mine, thank you:-)
b is physical. c is physical. Your answers of chemical should be answered this way. If they are chemical reactions, what DIFFERENT substances were formed when the canyon was formed? What DIFFERENT substances were formed when rocks were worn down by wave action?
Actually, the correct categorization of these geological changes is as follows:
a) formation of a limestone cave - chemical
b) creation of a canyon by a river - physical
c) wearing of rocks by wave action - physical
d) destruction of lakes by acid rain - chemical
e) heaving of the ground by ice formation - physical
So, the correction is that options a, d, and b should be categorized as chemical changes, while options c and e should be categorized as physical changes.
Actually, all of the geological changes that you mentioned can be classified as physical changes. Here's the correct classification for each:
a) Formation of a limestone cave - Physical change: This process occurs through the physical weathering of limestone rocks, where water erodes and dissolves the calcium carbonate to create the cave.
b) Creation of a canyon by a river - Physical change: Canyons are formed through the physical processes of erosion and abrasion by a river over a long period of time.
c) Wearing of rocks by wave action - Physical change: Waves can cause mechanical weathering by pounding rocks against each other, gradually fragmenting and wearing them down.
d) Destruction of lakes by acid rain - Chemical change: Acid rain is formed when sulfur dioxide and nitrogen oxides emitted by human activities react with water in the atmosphere, producing sulfuric acid and nitric acid. These acids can lower the pH of lakes, resulting in the chemical alteration and destruction of aquatic ecosystems.
e) Heaving of the ground by ice formation - Physical change: This process, known as frost heaving, occurs when water in the soil freezes and expands, exerting pressure on the surrounding materials and pushing the ground upward.
So, the correction is that a, b, c, and e are all physical changes, while d is the only example of a chemical change.