Question

1. fill in the missing items in the table below.

name	symbol	z	a	# protons	# electrons	# neutrons	isotopic symbol
b.		17			18
c. potassium
d.	p
e. iron					24
f.				53
g. silver
h.		36
i.	w
j.		29

Explanation:

Step1: Recall atomic number (Z) and proton - electron relationship

The atomic number (Z) is equal to the number of protons. In a neutral atom, the number of electrons is equal to the number of protons. The mass number (A) is the sum of protons and neutrons ($A = \text{# Protons}+\text{# Neutrons}$). The isotopic symbol is written as $_{Z}^{A}\text{Element - symbol}$.

Step2: Analyze row a (Sodium)

Sodium has atomic number $Z = 11$. So, \# Protons = 11, \# Electrons = 11 (for neutral atom). Commonly, sodium has a mass number $A=23$, then \# Neutrons=$A - \text{# Protons}=23 - 11 = 12$. Isotopic symbol is $_{11}^{23}\text{Na}$.

Step3: Analyze row b

$Z = 17$ is chlorine. Since \# Electrons = 18, it is a chloride ion ($Cl^-$). \# Protons = 17. If we assume a common isotope with $A = 35$, \# Neutrons=$A - \text{# Protons}=35 - 17 = 18$. Isotopic symbol is $_{17}^{35}\text{Cl}^-$.

Step4: Analyze row c

Potassium has symbol $K$ and $Z = 19$. For a neutral atom, \# Protons = 19, \# Electrons = 19. Commonly, $A = 39$, so \# Neutrons=$A - \text{# Protons}=39 - 19 = 20$. Isotopic symbol is $_{19}^{39}\text{K}$.

Step5: Analyze row d

$P$ is phosphorus with $Z = 15$. For a neutral atom, \# Protons = 15, \# Electrons = 15. Commonly, $A = 31$, so \# Neutrons=$A - \text{# Protons}=31 - 15 = 16$. Isotopic symbol is $_{15}^{31}\text{P}$.

Step6: Analyze row e

Iron has symbol $Fe$ and $Z = 26$. \# Protons = 26. Since \# Neutrons = 24, $A=\text{# Protons}+\text{# Neutrons}=26 + 24=50$. \# Electrons = 26 (for neutral atom). Isotopic symbol is $_{26}^{50}\text{Fe}$.

Step7: Analyze row f

\# Protons = 53 is iodine. For a neutral atom, \# Electrons = 53. Commonly, $A = 127$, so \# Neutrons=$A - \text{# Protons}=127 - 53 = 74$. Isotopic symbol is $_{53}^{127}\text{I}$.

Step8: Analyze row g

Silver has symbol $Ag$ and $Z = 47$. For a neutral atom, \# Protons = 47, \# Electrons = 47. Commonly, $A = 107$, so \# Neutrons=$A - \text{# Protons}=107 - 47 = 60$. Isotopic symbol is $_{47}^{107}\text{Ag}$.

Step9: Analyze row h

$Z = 36$ is krypton. For a neutral atom, \# Protons = 36, \# Electrons = 36. Commonly, $A = 84$, so \# Neutrons=$A - \text{# Protons}=84 - 36 = 48$. Isotopic symbol is $_{36}^{84}\text{Kr}$.

Step10: Analyze row i

$W$ is tungsten with $Z = 74$. For a neutral atom, \# Protons = 74, \# Electrons = 74. Commonly, $A = 184$, so \# Neutrons=$A - \text{# Protons}=184 - 74 = 110$. Isotopic symbol is $_{74}^{184}\text{W}$.

Step11: Analyze row j

$Z = 29$ is copper. For a neutral atom, \# Protons = 29, \# Electrons = 29. Commonly, $A = 63$, so \# Neutrons=$A - \text{# Protons}=63 - 29 = 34$. Isotopic symbol is $_{29}^{63}\text{Cu}$.

Answer:

NAME	SYMBOL	Z	A	# PROTONS	# ELECTRONS	# NEUTRONS	ISOTOPIC SYMBOL
Chloride	Cl	17	35	17	18	18	$_{17}^{35}\text{Cl}^-$
Potassium	K	19	39	19	19	20	$_{19}^{39}\text{K}$
Phosphorus	P	15	31	15	15	16	$_{15}^{31}\text{P}$
Iron	Fe	26	50	26	26	24	$_{26}^{50}\text{Fe}$
Iodine	I	53	127	53	53	74	$_{53}^{127}\text{I}$
Silver	Ag	47	107	47	47	60	$_{47}^{107}\text{Ag}$
Krypton	Kr	36	84	36	36	48	$_{36}^{84}\text{Kr}$
Tungsten	W	74	184	74	74	110	$_{74}^{184}\text{W}$
Copper	Cu	29	63	29	29	34	$_{29}^{63}\text{Cu}$