Question

complete the following table with the appropriate data for each isotope given (all are neutral atoms): element symbol atomic number mass number number of protons number of neutrons number of electrons chlorine ³⁶cl 17 36 17 19 17 gold au 79 197 197 79 118 79 iron fe 26 56 26 30 79

Explanation:

Step1: Recall atomic - related concepts

For a neutral atom, the atomic number ($Z$) is equal to the number of protons and the number of electrons. The mass number ($A$) is the sum of the number of protons and neutrons, i.e., $A =$ number of protons+number of neutrons.

Step2: Analyze the fourth row

Given number of neutrons = 20 and number of electrons = 18. Since number of electrons = number of protons for a neutral atom, number of protons = 18. The atomic number of the element with 18 protons is argon, symbol $Ar$. The mass number $A=$ number of protons + number of neutrons = 18 + 20=38.

Step3: Analyze the fifth row

Given mass number $A = 58$ and number of protons = 28. The element with 28 protons is nickel, symbol $Ni$. The number of neutrons = mass number - number of protons = 58 - 28 = 30. Since it is a neutral atom, the number of electrons is equal to the number of protons, so number of electrons = 28.

Answer:

Element	Symbol	Atomic number	Mass number	Number of protons	Number of neutrons	Number of electrons
Gold	$Au$	79	197	79	118	79
iron	$Fe$	26	56	26	30	26
argon	$Ar$	18	38	18	20	18
nickel	$Ni$	28	58	28	30	28