If you have a concern about fluoride in your drinking water, you can get more information by contacting the local community water system and is denoted as option D.
<h3>What is Water?</h3>
This is referred to as a universal solvent and is usually colorless and used for various purposes such as drinking, washing etc.
Fluoride is added to water by the the community water system as it helkps to build strong teeth and cavities thereby preventing tooth decay. They know the concentration which is added to the water which is why they need to be contacted for more information.
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When the solution used begins to change color and stays the new color for at least 30 seconds we are able to tell that the solution has reached the end point of titration
ZnS(s) + 2O₂(g) ⇒ZnSO₄(s)
<h3>Further explanation</h3>
The oxidation-reduction reaction or abbreviated as Redox is a chemical reaction in which there is a change in oxidation number
Oxidation is an increase in oxidation number, while reduction is a decrease in oxidation number.
Reaction
ZnS(s) + 2O₂(g) ⇒ZnSO₄(s)
S²⁻ (-2 in ZnS) to S⁺⁶(+6 in ZnSO₄) ⇒ oxidation
O₂(0 in O₂) to O⁻²(-2 in ZnSO₄)⇒ reduction
Answer: All cells are made from the same major classes of organic molecules: nucleic acids, proteins, carbohydrates, and lipids.
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