Most of the chemicals included in your introductory chemistry lab kit can be discarded down a drain with copious amounts of water. describe a situation in which you would need to neutralize a chemical (ph 7) before discarding down a drain

Explanation:

To neutralize a chemical to a pH of 7 before discarding, one would require a significant amount of acids or bases. Our best guess is that the solution in itself is either an acid or a base. Neutralization with the right amount of a proper reagent can bring the pH of the solution to a neutral 7.

If the solution has a pH originally greater than 7, add a corresponding amount of acid to it. This will reduce the concentration and bring it to a neutral point. Provided one is dealing with a solution of pH less than 7, simply add a base to to bring the solution to neutrality.

Remember, the term pH (or pH value) is a standard measure of the level of acidity/basicity of a chemical solution. The pH value typically ranges from 0 to 14, where a solution with pH 7 is referred to as being neutral. While chemical solutions with pH values greater than 7 are base, meanwhile those lower than 7 indicate acidity.

In this instance, we want the chemical solution to become neutral (ie. to a have pH of 7). Logically this implies that this chemical solution should either be an acid or a base, but not neutral.

Scenario 1:

the chemical solution is a base, i.e it has pH values greater than 7: adding the right amounts of acid to the base should cause a reaction that would make the chemical solution neutral.

Scenario 2:

the chemical solution is an acid, i.e it has a pH lower than 7. In this case, adding the right amounts of a base solution to the acid should make neutrality.

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answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e