Answer:
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Karsts are found in widely scattered sections of the world, including the Causses of France; the Kwangsi area of China; the Yucatán Peninsula; and the Middle West, Kentucky, and Florida in the United States.
Explanation:
Answer:
c
Explanation:
it makes sense and the diagram is build like that with high tech
Answer:
Valence electrons
Explanation:
In a period, the number of valence electrons increases (mostly for light metal/elements) as we move from left to right side
Answer:
Excess Reagent = oxygen
Explanation:
Limiting reagent: The substance that is totally consumed when the reaction is completed.
Excess reagent: The substance left after the limiting reagent is consumed completely
The balanced chemical equation for formation of water is as follow:

This means when 2 moles of hydrogen reacts with 1 mole of oxygen, 2 moles of water is produced.
Hence the ratio in which hydrogen and oxygen gas reacts is 2:1
Now if 2 mole hydrogen require 1 mole of oxygen ,then 4 mole hydrogen need 2 mole of oxygen.

or

Here 5 mole of oxygen is reacting but only 2 mole is required .
Oxygen is in excess.