Answer:
Negative fame
Explanation:
I looked it up in a dictionary and also passage clues.
Limestone
Limestone is easily broken down by the carbonic acid found in ground water
Warm/Humid
Chemical weathering is most active in warm and humid climates
Valleys
Limestone regions tend to be valleys because of the chemical weathering of the rock by ground water
Oxidation
The process by which oxygen reacts with iron minerals in rock to form rust is called oxidation
Chemical weathering
Process by which rock minerals are change by natural processes into the new substance is known as chemical weathering
Climate/rock type
The rate of weathering in a region is a term in mostly by climate and rock type
Weak Acid
Ground water is a weak acid known as carbonic acid, which will chemically alter the minerals in certain types of rock
Week acid/chemically
Caverns and sinkholes are for one week acid and groundwater react slowly with limestone causing it to change chemically
