ACS Chemistry 131 FINAL EXAM Questions and Correct Answers/ Latest Update / Already Graded

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ACS Chemistry 131 FINAL EXAM
Questions and Correct Answers/ Latest
Update / Already Graded
Atomic Structures

Ans: Know all the problems except #7,14,15


When looking at the atomic structure what does the left-hand
subscript represent

Ans: Left hand subscript = atomic number


When looking at the atomic structure what does the left-hand
superscript represent

Ans: The mass number


Where on the atomic structure would we find the ionic change (if the
isotope has one)

Ans: On the right hand super-script


The mass number = a combination of what two things




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Ans: Mass number is the sum of all the number of protons and
neutrons


The atomic number equals what?

Ans: The atomic number = the number of protons
- Found on left side subscript


If there is no charge on the isotope what can we assume about its # of
electrons

Ans: We can assume that its number of electrons is equal to its
number of protons


What is the definition of an isotope

Ans: Isotopes are forms of the same element that differ only in
their number of neutrons in the nuclei


- Atomic models will be the same with same subscripts on the
left but different superscripts on the left


Give an example of an isotope

Ans: ²³⁵U and ²³⁸U


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