Question

part 2b 10 marks
choose 5 of 6
(lesson 2a)
write the atomic notation for the following items
a) neptunium - 237
b) an element with 95 protons, 96 electrons, & 146 neutrons
c) darmstadtium - 281
d) an element 118 protons, 121 electrons, & 174 neutrons
e) thulium - 169
f) an element with 107 protons, 110 electrons, & 162 neutrons

Explanation:

Step1: Recall atomic notation

Atomic notation is $\ce{_{Z}^{A}X^{n\pm}}$, where $Z$ is the atomic number (number of protons), $A$ is the mass - number (sum of protons and neutrons), $X$ is the chemical symbol of the element, and $n\pm$ is the charge (number of electrons different from number of protons).

Step2: Find atomic notation for a) Neptunium - 237

Neptunium has atomic number $Z = 93$. Mass number $A=237$. Chemical symbol is $\ce{Np}$. So the atomic notation is $\ce{_{93}^{237}Np}$.

Step3: Find atomic notation for b)

Atomic number $Z = 95$ (number of protons), so the element is Americium ($\ce{Am}$). Mass number $A=95 + 146=241$. There is 1 more electron than proton, so charge is $1-$. Atomic notation is $\ce{_{95}^{241}Am^{1 -}}$.

Step4: Find atomic notation for c) Darmstadtium - 281

Darmstadtium has atomic number $Z = 110$. Mass number $A = 281$. Chemical symbol is $\ce{Ds}$. Atomic notation is $\ce{_{110}^{281}Ds}$.

Step5: Find atomic notation for d)

Atomic number $Z = 118$, so the element is Oganesson ($\ce{Og}$). Mass number $A=118 + 174=292$. There are 3 more electrons than protons, so charge is $3-$. Atomic notation is $\ce{_{118}^{292}Og^{3 -}}$.

Step6: Find atomic notation for e) Thulium - 169

Thulium has atomic number $Z = 69$. Mass number $A = 169$. Chemical symbol is $\ce{Tm}$. Atomic notation is $\ce{_{69}^{169}Tm}$.

Step7: Find atomic notation for f)

Atomic number $Z = 107$, so the element is Bohrium ($\ce{Bh}$). Mass number $A=107+162 = 269$. There are 3 more electrons than protons, so charge is $3-$. Atomic notation is $\ce{_{107}^{269}Bh^{3 -}}$.

Answer:

a) $\ce{_{93}^{237}Np}$
b) $\ce{_{95}^{241}Am^{1 -}}$
c) $\ce{_{110}^{281}Ds}$
d) $\ce{_{118}^{292}Og^{3 -}}$
e) $\ce{_{69}^{169}Tm}$
f) $\ce{_{107}^{269}Bh^{3 -}}$