Answer
a. $^{58}_{27}Co$
b. $^{10}_5B$
c. $^{23}_{12}Mg$
d. $^{132}_{53}I$
e. $^{47}_{20}Ca$
f. $^{65}_{29}Cu$
Work Step by Step
We refer to the periodic table when determining the element. Note that the formula $^A_ZX$ represents an atom with a mass number of A and an atomic number of Z. Therefore, we may write the following:
a.
Atomic mass = number of protons + number of neutrons = 27+31=58.
The element with 27 protons is Cobalt (CO).
Therefore the formula is $^{58}_{27}Co$.
b.
Boron has an atomic number of 5.
Therefore the formula is $^{10}_5B$.
c.
Magnesium (Mg) has 12 protons.
$^{23}_{12}Mg$
d.
The element with an atomic number of 53 is Iodine (I).
Atomic mass = number of protons + number of neutrons = 53+79 = 132.
$^{132}_{53}I$
e.
The element with an atomic number of 20 is Calcium (Ca).
Atomic mass = number of protons + number of neutrons = 20+27=47.
$^{47}_{20}Ca$
f.
The element with 29 protons is Copper (Cu).
$^{65}_{29}Cu$
