Answer:
the answer of the question is c
Elements are substances that are made up of the same atoms which are capable of taking part in a chemical reaction.
There are different types of elements which are represented by symbols gotten from the first letter or the first and any other letter in the name of the element.
Examples of elements include:
When two or more of these elements combine together through a chemical bond, it leads to the formation of compounds.
Example of a compound includes:
- NaCl: The element sodium combine, through electrochemical bonding, with another element chlorine to form the compound sodium chloride.
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brainly.com/question/17571315
The solution changed color because the substances are not neutral.
<h3>
pH</h3>
Chemical substances have different concentrations of the hydrogen cation, called PH.
The higher the pH, the more basic the substance, and the lower the more acidic.
Bromothymol blue is a pH indicator that changes its color according to the pH of the substance, yellow for acid, blue for basic and green for neutral.
In the case of the reactions in question, we have the release of CO2 (acid) in combustion and in cellular respiration, changing the color of bromothymol blue to yellow.
Learn more about pH in: brainly.com/question/491373