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Copy of Isotopes - Models (5/28/2026)

Last updated about 2 hours ago

18 questions

4

4

2

1

1

1

3

Question 1

1.

6

Question 2

2.

6

Question 3

3.

6

Question 4

4.

2

Question 5

5.

1

Question 6

6.

1

1

Question 8

8.

6

Question 9

9.

2

Question 10

10.

4

Question 11

11.

Question 12

12.

Examine the isotope for potassium (K) and answer the following:
a.) Atomic # _______ 
b.) Mass # _______ 
c.) # p+ _______ 
d.) # n _______ 

Question 13

13.

Examine the isotope for fluorine (F) and answer the following:
a.) Atomic # _______ 
b.) Mass # _______ 
c.) # p+ _______ 
d.) # n _______ 

Question 14

14.

The following is known about an isotope:
Atomic # 16
# n = 15

Use the above information to answer the following:
a.) Mass # _______ 
b.) # p+ _______ 
c.) Use the periodic table to identify the atom. _______ 

4

Question 15

15.

Question 16

16.

Consider your answers to #15 and create your own definition of "isotope," using your own words - this means, do not look anything up.

Question 17

17.

Identify all of the following that are isotopes of each other.

Question 18

18.

In answering question 17, which part of the isotope symbols were the most helpful to you. _______ 

Refer to Model 1. What subatomic particles do the following symbols represent in the Atomic Diagrams?

_______ 

_______ 

_______

Hydrogen-1
protons _______ 
neutrons _______ 

Hydrogen-2
protons _______ 
neutrons _______ 

Hydrogen-3
protons _______
neutrons _______  

Carbon-12
protons _______ 
neutrons _______ 

Carbon-13
protons _______ 
neutrons _______ 

Carbon-14
protons _______
neutrons _______  

Magnesium-24
protons _______ 
neutrons _______ 

Magnesium-25
protons _______ 
neutrons _______ 

Magnesium-26
protons _______
neutrons _______  

Find, H, C, and Mg on the periodic table. 

a.) What whole number is shown for each element of Model 1 that is also shown as a decimal on the periodic table? (what is it called - not the actual number)? _______ 

b.) Refer to the element symbols on Model 1. Where is the atomic number located on the isotope symbols? _______ 

Refer to the piece of the periodic table, to the left.
How many protons are in all Cl atoms? _______ 

Question 7

7.

Someone stated, "I think some chlorine atoms have 16 protons." Explain why this person is incorrect.

Refer again to Model 1. In the isotope symbol of each atom, there is a superscripted (raised) number. This number is also used in the name of the atom (i.e., carbon-12). It is called the mass number.

a.) How is the mass number (atomic mass) determined? _______ 

Consider #1, where you defined each subatomic symbol (electrons, protons, and neutrons). Use that knowledge as well as what you know about how the mass number is calculated to complete the following for Atom I and II (left):

Atom I:
Protons _______ 
Neutrons _______ 
Mass Number _______ 

Atom II:
Protons _______ 
Neutrons _______ 
Mass Number _______ 

Refer to Model 1.

a.) Which corner of the isotope symbol contains the mass number? _______ 
b.) How is the mass number of an isotope expressed in the name of an atom? _______ 

Consider how the mass number and atomic number is expressed around an isotope symbol (refer to the isotope symbols of Model 1, if necessary - prior question). Think about the isotope symbols that would exist for Atom I and II (left).

Atom 1:
What number would go to the upper-left? _______  
What number would go to the lower-left? _______ 

Atom 2:
What number would go to the upper-left? _______ 
What number would go to the lower-left? _______ 

Refer to Model 1. 

a.) Do all isotopes of an element have the same atomic number? _______ 
b.) Provide one example from Model 1 to support your answer. _______ 

c.) Do all isotopes have the same mass number? _______ 
d.) Provide one example from Model 1 to support your answer. _______ 