What is chemical weathering?
Chemical weathering is when the rocks have been broken down by chemical reactions. Rain that is acidic can break through the rock. For example, the acid changes the chemicals in limestone so that it crumbles easily. No two rocks are the same. The rocks are different than they were before chemical weathering occured.
Different ways of Chemical Weathering
There are a few different ways of chemical weathering such as:
Hydrolysis
Hydrolysis is when a substance combines with water and a chemical breakdown occurs. An example is when water comes in contact with granite and the substance inside the granite called feldspar reacts with the water to form clay. A easy way to remember this is when you think of making a cup of coffee. The hot water inside a coffee maker gets filtered by the coffee grains. This makes a chemically different substance called coffee.
Oxidization
Oxidization is what causes rust. The oxygen in the air reacts with the iron and forms iron oxide. Iron oxide, which is less strong than iron, can easily be broken by a fingertip. This can happen in a rock if it contains iron. When this happens to a rock, it crumbles very easily. Iron oxide is reddish-brown in color, this explains why some rocks are red.
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Carbonation
When water mixes with carbon dioxide, it makes carbonic acid. Carbonic acid is part of the process in carbonation. This kind of weathering is important in making caves. Carbonic acid reacts with the minerals in rock, such as calcite, which is commonly found in limestone. The mineral is vurnerable to carbonation, so it dissolves in the carboonic acid and gets washed away. This can hollow the rock and leave a cave.
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