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Answer:</h3>
200 molecules of water has the highest concentration.
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Explanation:</h3>
In chemistry, Concentration is defined as the amount of substance divided by the total volume of the constituents making the mixture.
<u>Case 1:</u> 200 Molecules of Water:
In this case we are having system which is made up of 200 purely water molecules and there is no other substance present in the system. Hence, for ease we can write it as,
Concentration = Molecules of Water ÷ Total Molecules of Mixture
Concentration = 200 ÷ 200
Concentration = 1
<u>Case 2:</u> 300 Molecules of Water and 100 Molecules of Food Coloring:
In this case we are having a mixture which is made up of 300 water molecules and 200 food coloring molecules. Hence, we can write it as,
Concentration = Molecules of Water ÷ Total Molecules of Mixture
Concentration = 300 ÷ (300 + 200)
Concentration = 300 ÷ 500
Concentration = 0.6
Therefore, it is proved that the concentration of pure 200 molecules of water is greater.
* 100% = 36.23 %