Question

fill in the information missing from this table.

nuclide	protons	neutrons	z	a
$_{77}^{191}$ir
	69	100

Explanation:

Step1: Recall atomic number and mass - number definitions

The atomic number $Z$ is equal to the number of protons. The mass - number $A$ is the sum of the number of protons and neutrons ($A =$ protons+neutrons).

Step2: Fill the first row

Since $Z = 13$, the number of protons is 13. Using $A=27$ and $A =$ protons + neutrons, we can find the number of neutrons: neutrons=$A -$ protons. So neutrons=$27 - 13=14$. The nuclide with $Z = 13$ is aluminum, written as $^{27}_{13}Al$.

Step3: Fill the second row

For $^{191}_{77}Ir$, the atomic number $Z = 77$, so the number of protons is 77. The number of neutrons is $A -$ protons, so neutrons=$191 - 77 = 114$. And $A = 191$, $Z = 77$.

Step4: Fill the third row

The number of protons is 69, so $Z = 69$. The element with $Z = 69$ is thulium, written as $^{169}_{69}Tm$. The mass - number $A=$ protons + neutrons, so $A=69 + 100=169$.

Answer:

nuclide	protons	neutrons	$Z$	$A$
$^{191}_{77}Ir$	77	114	77	191
$^{169}_{69}Tm$	69	100	69	169