Question

1. what is the symbolic notation for an atom with 8 protons and 10 neutrons.

18 10cr
18 10o
18 8o

Explanation:

Step1: Recall atomic - notation rules

The symbolic notation for an atom is $_{Z}^{A}X$, where $Z$ is the atomic number (number of protons) and $A$ is the mass number (number of protons + number of neutrons).

Step2: Determine the atomic number

Given 8 protons, so $Z = 8$.

Step3: Determine the mass number

Number of protons is 8 and number of neutrons is 10. Mass number $A=8 + 10=18$.

Step4: Identify the element

The element with atomic number $Z = 8$ is oxygen, symbolized as $O$.

Answer:

$_{8}^{18}O$