Question

1. determine the number of protons, neutrons and electrons in the following: (4 pts)

potassium k 19 39.098
tellurium te 52 127.60
p+ n° e- __
p+ n° e- __

Explanation:

Step1: Recall atomic number rule

The atomic number ($Z$) is equal to the number of protons and for a neutral - atom, the number of electrons. For potassium ($K$), the atomic number $Z = 19$. So, the number of protons $p^{+}=19$ and the number of electrons $e^{-}=19$. The mass number ($A$) is approximately 39.098. The number of neutrons $n^{0}=A - Z$. So, $n^{0}=39 - 19=20$.

Step2: Analyze tellurium

For tellurium ($Te$), the atomic number $Z = 52$. So, the number of protons $p^{+}=52$ and the number of electrons $e^{-}=52$. The mass number $A = 127.60$. Rounding the mass number to 128, the number of neutrons $n^{0}=A - Z=128 - 52 = 76$.

Answer:

Potassium ($K$): Protons: 19, Neutrons: 20, Electrons: 19
Tellurium ($Te$): Protons: 52, Neutrons: 76, Electrons: 52