Chapter 2, Problem 2.41P

a)

Interpretation Introduction

Interpretation:The name, atomic symbol and group number of the element $\text{Z}$ value 32 should be given and whether it is metal, metalloid or non-metal should be classified.

Concept introduction:Total number of protons in an element is known as its atomic number and it is represented with symbol $\left(\text{Z}\right)$ . Also in any atom has equal number of protons and electrons to maintain its electrical neutrality. Mass number $\left(\text{A}\right)$ of any isotope of an element is determined by the addition of its atomic number $\left(\text{Z}\right)$ with its neutron number $\left(\text{N}\right)$ .

To maintain neutrality of a nucleus, number of protons and number electrons should be same.The group number is vertical axis in a periodic table. There are 18 groups in a periodic table.

Metals are elements which readily forms positive ions and shows conductivity. Non- metals are elements that don’t show conductivity like metals. Metalloids show properties in between metals and non-metals.

Explanation of Solution

Atomic number of germanium is 32 in accordance with the modern periodic table.

Atomic symbol of germanium is $\text{Ge}$ . Electronic configuration of phosphorous is $1{\text{s}}^{2}2{\text{s}}^{2}2{\text{p}}^{6}3{\text{s}}^{2}3{\text{p}}^{6}3{\text{d}}^{10}4{\text{s}}^{2}4{\text{p}}^2$ .

Formula to calculate group number of an atom is as follows:

  $\text{Number}\text{of}\text{group}=\left(12+\text{Number}\text{of}\text{electrons}\text{in}\text{last}\text{p}\text{subshell}\right)$

Number of electrons in last p subshell of germanium is 2.

Substitute the value in the above equation.

  $\begin{array}{c}\text{Number}\text{of}\text{group}=\left(12+\text{Number}\text{of}\text{electrons}\text{in}\text{last}\text{p}\text{subshell}\right)\\ =\left(12+2\right)\\ =14\end{array}$

So, it will be placed in the 14^th group of the periodic table.

The elements that touch the staircase type are considered as metalloids.Hence.germanium touches the staircase type. So, it will be metalloid.

b)

Interpretation Introduction

Interpretation: The name, atomic symbol and group number of the element $\text{Z}$ value 15 should be given and whether it is metal, metalloid or non-metal should be classified.

Concept introduction:Total number of protons in an element is known as its atomic number and it is represented with symbol $\left(\text{Z}\right)$ . Also in any atom has equal number of protons and electrons to maintain its electrical neutrality. Mass number $\left(\text{A}\right)$ of any isotope of an element is determined by the addition of its atomic number $\left(\text{Z}\right)$ with its neutron number $\left(\text{N}\right)$ .

To maintain neutrality of a nucleus, number of protons and number electrons should be same. The group number is vertical axis in a periodic table. There are 18 groups in a periodic table.

Metals are elements which readily forms positive ions and shows conductivity. Non- metals are elements that don’t show conductivity like metals. Metalloids show properties in between metals and non-metals.

Explanation of Solution

Atomic number of phosphorous is 15 in accordance with the modern periodic table.

Atomic symbol of phosphorous is $\text{P}$ . Electronic configuration of phosphorous is $1{\text{s}}^{2}2{\text{s}}^{2}2{\text{p}}^{6}3{\text{s}}^{2}3{\text{p}}^3$ .

Formula to calculate the group number of an atom is as follows:

  $\text{Number}\text{of}\text{group}=\left(12+\text{Number}\text{of}\text{electrons}\text{in}\text{last}\text{p}\text{subshell}\right)$

Number of electrons in last p subshell of phosphorous is 5.

Substitute the value in the above equation.

  $\begin{array}{c}\text{Number}\text{of}\text{group}=\left(12+\text{Number}\text{of}\text{electrons}\text{in}\text{last}\text{p}\text{subshell}\right)\\ =\left(12+3\right)\\ =15\end{array}$

So, it will be placed in 15^th group of the periodic table. Phosphorous doesn’t touch the staircase type and placed right of the staircase. Hence, it is non-metal.

c)

Interpretation Introduction

Interpretation: The name, atomic symbol and group number of the element $\text{Z}$ value 2 should be given and whether it is metal, metalloid or non-metal should be classified.

Concept introduction:Total number of protons in an element is known as its atomic number and it is represented with symbol $\left(\text{Z}\right)$ . Also in any atom has equal number of protons and electrons to maintain its electrical neutrality. Mass number $\left(\text{A}\right)$ of any isotope of an element is determined by the addition of its atomic number $\left(\text{Z}\right)$ with its neutron number $\left(\text{N}\right)$ .

To maintain neutrality of a nucleus, number of protons and number electrons should be same. The group number is vertical axis in a periodic table. There are 18 groups in a periodic table.

Metals are elements which readily forms positive ions and shows conductivity. Non- metals are elements that don’t show conductivity like metals. Metalloids show properties in between metals and non-metals.

Explanation of Solution

Atomic number of helium is 2 in accordance with the modern periodic table.

Atomic symbol of helium is $\text{He}$ . Electronic configuration of helium is $1{\text{s}}^2$ .

All noble gases are placed in 18^th group of the modern periodic table.

Helium doesn’t touch the staircase type and placed right of the staircase. Hence, it is non-metal.

d)

Interpretation Introduction

Interpretation: The name, atomic symbol and group number of the element $\text{Z}$ value 3 should be given and whether it is metal, metalloid or non-metal should be classified.

Concept introduction:Total number of protons in an element is known as its atomic number and it is represented with symbol $\left(\text{Z}\right)$ . Also in any atom has equal number of protons and electrons to maintain its electrical neutrality. Mass number $\left(\text{A}\right)$ of any isotope of an element is determined by the addition of its atomic number $\left(\text{Z}\right)$ with its neutron number $\left(\text{N}\right)$ .

To maintain neutrality of a nucleus, number of protons and number electrons should be same. The group number is vertical axis in a periodic table. There are 18 groups in a periodic table.

Metals are elements which readily forms positive ions and shows conductivity. Non- metals are elements that don’t show conductivity like metals. Metalloids show properties in between metals and non-metals.

Explanation of Solution

Atomic number of lithium is 3 in accordance with the modern periodic table.

Atomic symbol of lithium is $\text{Li}$ . Electronic configuration of lithium is $1{\text{s}}^{2}2{\text{s}}^1$ .

Formula to calculate the group number of an atom is as follows:

  $\text{Number}\text{of}\text{group}=\left(\text{Number}\text{of}\text{electrons}\text{in}\text{last}s\text{subshell}\right)$

The number of electrons in the last s subshell is 1.

Substitute the value in the above equation.

  $\begin{array}{c}\text{Number}\text{of}\text{group}=\left(\text{Number}\text{of}\text{electrons}\text{in}\text{last}s\text{subshell}\right)\\ =1\end{array}$

So, lithium will be placed in the 1^st group of modern periodic table

elements that placed left to the staircase are considered as metals.Here lithium doesn’t touch the staircase type and placed left of the staircase.So, it is a metal.

e)

Interpretation Introduction

Interpretation: The name, atomic symbol and group number of the element $\text{Z}$ value 42 should be given and whether it is metal, metalloid or non-metal should be classified.

Concept introduction:Total number of protons in an element is known as its atomic number and it is represented with symbol $\left(\text{Z}\right)$ . Also in any atom has equal number of protons and electrons to maintain its electrical neutrality. Mass number $\left(\text{A}\right)$ of any isotope of an element is determined by the addition of its atomic number $\left(\text{Z}\right)$ with its neutron number $\left(\text{N}\right)$ .

To maintain neutrality of a nucleus, number of protons and number electrons should be same. The group number is vertical axis in a periodic table. There are 18 groups in a periodic table.

Metals are elements which readily forms positive ions and shows conductivity. Non- metals are elements that don’t show conductivity like metals. Metalloids show properties in between metals and non-metals.

Explanation of Solution

Atomic number of molybdenum is 42 in accordance with the modern periodic table.

Atomic symbol of molybdenum is $\text{Mo}$ . Electronic configuration of molybdenum is $1{\text{s}}^{2}2{\text{s}}^{2}2{\text{p}}^{6}3{\text{s}}^{2}3{\text{p}}^{6}3{\text{d}}^{10}4{\text{s}}^{2}4{\text{p}}^{2}4{\text{d}}^{5}5{\text{s}}^1$ .

Molybdenum is present in 6^th group of periodic table. Elements that are placed left to staircase are considered as metals. Molybdenum doesn’t touch staircase type and placed left of the staircase.So, molybdenumis a metal.