The answer is 7, the neutrons and electrons are given and in any chemistry synopsis the protons are the same as the electrons vise versa
The statement that best describes what is happening in the following reaction is this is not a redox reaction, It is an example of combustion (option A).
<h3>What is a combustion reaction?</h3>
A combustion reaction is a reaction wherein a substance is combined with oxygen, usually at high temperature, releasing heat.
According to this question, octane undergoes a combustion reaction to produce carbon dioxide and water as follows: 2C8H18 + 25O2 = 16CO2 + 18H2O
Therefore, the statement that best describes what is happening in the following reaction is this is not a redox reaction, It is an example of combustion.
Learn more about combustion at: brainly.com/question/12172040
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Answer:
The atomic mass of element X is 69.724 amu
Explanation:
Given data:
Atomic mass of element X= ?
Percent abundance of X-68.926 = 60.10%
percent abundance of X-70.925 = 39.90%
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (68.926×60.10)+(70.925×39.90) /100
Average atomic mass = 4142.4526 +2829.9075/ 100
Average atomic mass = 6972.3601 / 100
Average atomic mass = 69.724 amu.
The atomic mass of element X is 69.724 amu.
A controled variable is the variable that remains the same.