Selina solutions for Concise Chemistry [English] Class 10 ICSE chapter 1 - Periodic Table, Periodic Properties and Variations of Properties [1990 edition]

State modern periodic law.

Name the scientist who stated the modern periodic law.

How many groups and periods does the modern periodic table have?

What are horizontal rows and vertical columns in a periodic table known as?

Periodicity is observed due to the similar ______.

How does the electronic configuration in atoms change in a period from left to right?

How does the electronic configuration in atoms change in a group from top to bottom?

Name two elements in Alkali metals.

Name two elements in Alkaline earth metals.

Name two elements in halogens.

Name two elements in Inert gas.

Elements of group 1 and elements of group 17 both have valency 1. Explain.

Correct the statement.

Elements in the same period have the same valency.

Correct the statement.

Valency depends upon the number of shells in an atom.

Correct the statement.

Copper and zinc are representative elements.

Correct the statement.

Transition elements are placed at extreme right of the periodic table.

What do you understand by periodicity?

What do you understand by typical elements?

What do you understand by orbits?

Name two elements that you would expect to show chemical reactions similar to calcium. What is the basis of your choice?

Name the metals in the first twenty elements.

Name the metalloids in the first twenty elements.

Name the non-metals in the first twenty elements.

Fluorine, chlorine and Bromine are put in one group on the basis of their similar properties.

What are those similar properties?

Fluorine, chlorine and Bromine are put in one group on the basis of their similar properties.

What is the common name of this group or family?

What is the main characteristic of the last element in each period of the periodic table?

What is the general name of the last elements of the Periodic Table?

According to atomic structure, what determines which element will be the first and which will be the last in a period?

How does number of valence electrons vary on moving from left to right in the third period of a periodic table?

How does the number of valency vary on moving from left to right in the third period of the periodic table?

Name the type of elements which have outermost shell complete.

Name the type of elements which have outermost shell incomplete.

Name the type of elements which have two outermost shell incomplete.

Name the type of elements which have one electron short of octet.

Name the type of elements which have two electrons in the outermost orbit.

An element has 2 electrons in its N shell.

What is its atomic number?

An element has 2 electrons in its N shell.

State its position in periodic table.

An element has 2 electrons in its N shell.

Is it a metal or a non-metal?

An element has 2 electrons in its N shell.

State the name assigned to this group.

An element has 2 electrons in its N shell.

What is the valency of this element?

Answer the following in respect of element \[\ce{_16^32S}\].

Give its electronic configuration.

Answer the following in respect of element \[\ce{_16^32S}\].

To which group and period does it belong?

Answer the following in respect of element \[\ce{_16^32S}\].

What is its valency?

Answer the following in respect of element \[\ce{_16^32S}\].

Is it a metal or a non-metal?

Answer the following in respect of element \[\ce{_16^32S}\].

Is it a reducing agent or an oxidising agent?

Answer the following in respect of element \[\ce{_16^32S}\].

Give its formula with hydrogen.

Name an alkali metal in period 3 and halogen in period 2.

Name the noble gas with 3 shells.

Name the non-metals present in period 2 and metals in period 3.

Name the element of period 3 with valency 4.

Name the element in period 3 which does not form oxide.

Name the element of lower nuclear charge out of Be and Mg.

The electronic configuration of an element T is 2, 8, 8, 1.

What is the group number of T?

The electronic configuration of an element T is 2, 8, 8, 1.

What is the period number of T?

The electronic configuration of an element T is 2, 8, 8, 1.

How many valence electrons are there in an atom of T?

The electronic configuration of an element T is 2, 8, 8, 1.

What is the valency of T?

The electronic configuration of an element T is 2, 8, 8, 1.

Is it a metal or a non-metal?

Match the atomic number with the following:

A metal of valency one.

Match the atomic number with the following:

A solid non-metal of period 3.

Match the atomic number with the following:

A rare gas.

Match the atomic number with the following:

A gaseous element with valency 2.

Match the atomic number with the following:

An element of group 2.

What do you understand by atomic size? State its unit?

Give the trends in atomic size on moving down the group.

Give the trends in atomic size on moving across the period left to right.

Arrange the elements of second and third periods in increasing order of their atomic size (excluding noble gases).

Why is the size of neon greater than fluorine?

Why is the size of sodium is greater than magnesium?

Which is greater in size an atom or a cation?

Which is greater in size an atom or an anion?

Which is greater in size Fe²⁺ or Fe³⁺?

Which has higher E.A. fluorine or Neon?

Which has the maximum metallic character Na, Li or K?

Arrange:

Be, Li, C, B, N, O, F (in increasing metallic character).

Arrange:

Si, Na, Al, Mg, Cl, P, S (in decreasing non-metallic character).

State the trend in chemical reactivity across the third period left to right.

State the trend in chemical reactivity down the group in group IA (1).

State the trend in chemical reactivity down the group in group VIIA (17).

A metal M forms as oxide having the formula M₂O₃. It belongs to third period. Write the atomic number and valency of the metal.

An element X belongs to 3^rd period and 17^th group, state the no. of valence electrons in it.

An element X belongs to 3^rd period and 17^th group, state the name of the element.

An element X belongs to the 3^rd period and 17^th group, state the name of the family to which it belongs.

An element X belongs to the 3^rd period and 17^th group, write the formula of the compound formed when X reacts with \[\ce{_13^27Y}\].

The given table shows elements with the same number of electrons in its valence shell.

Whether these elements belong to same group or period.

The given table shows elements with the same number of electrons in its valence shell.

Arrange them in order of increasing metallic character.

Which one of the following has the largest atomic radius?

Which one has the largest size?

The metals of Group 2 from top to bottom are Be, Mg, Ca, Sr and Ba. Which one of these elements will form ions most readily and why?

The metals of Group 2 from top to bottom are Be, Mg, Ca, Sr and Ba. State the common feature in the electronic configuration.

Write the number of protons, neutrons and electronic configuration of \[\ce{_19^39K, _15^31P}\]. Also state their position in periodic table.

Name the element that has two shells, both of which are completely filled with electrons.

Name the element which has the electronic configuration 2, 8, 3?

Name the element which has a total of three shells with five electrons in its valence shell?

Name the element which has a total of four shells with two electrons in its valence shell?

Which element has twice as many electrons in its second shell as in its first shell?

An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.

Is it a metal or a non-metal?

An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.

Is it more or less reactive than calcium?

An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.

What is its valency?

An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.

What will be the formula of its phosphate?

An element barium has the atomic number 56. Look up its position in the periodic table and answer the following question.

Is it larger or smaller than caesium (Cs)?

ÅIn group I of the periodic table, three elements X, Y, and Z have ionic radii 1.33 Å, 0.95 Å and 0.60 Å respectively. Giving a reason, arrange them in the order of increasing atomic number in the group.

Explain why the following statement is not correct:

All groups contain metals and non metals.

Explain why the following statement is not correct:

Atoms of elements in the same group have the same number of electron(s).

Explain why the following statement is not correct:

Non-metallic character decreases across a period with increase in atomic number.

Explain why the following statement is not correct:

Reactivity increases with atomic number in a group as well as in a period.

State the number of elements in periods 1, Periods 2, and Period 3 of the periodic table. Name them.

What is the common feature of the electronic configuration of the elements at the end of Period 2 and Period 3?

If an element is in Group 17, it is likely to be ______ (metallic/non-metallic) in character, while with one electron in its outermost energy level (shell), then it is likely to be ______ (metallic/non-metallic).

In Period 3, the most metallic element is ______.

The properties of the elements are a periodic function of their __________.

Moving across a ______ of the Periodic table, the elements show increasing ______ character.

The elements at the bottom of a group would be expected to show ______ metallic character than the element at the top.

The similarities in the properties of a group of elements are because they have the same ______.

Give reason for the following:

The size of a Cl⁻ ion is greater than the size of a Cl atom.

Give reason for the following:

Argon atom is bigger than chlorine atom. 

Give reason for the following:

Ionisation potential of the element increases across a period.

Give reason for the following:

Inert gases do not form ion.

Define the term ‘ionisation potential`.

Represent ionisation potential in the form of an equation. In which unit it is measured?

Ionisation Potential values depend on atomic size. Explain.

Ionisation Potential values depend on the nuclear pull. Explain.

State the trends in ionization energy across the period.

State the trends in ionization energy down the group.

Name the elements with highest and lowest ionization energies in the first three periods.

Arrange the elements of second and third period in increasing order of ionization energy.

The element with highest ionisation potential is ______.

Define the term ‘electron affinity’.

State electron affinity unit.

Arrange the elements of second period in increasing order of their electron affinity. Name the elements which do not follow the trend in this period.

Electron affinity values generally _______ across the periods left to right and ______ down the group top to bottom.

Define the term Electronegativity.

Among the elements given below, the element with the least electronegativity is:

The most electronegative element from the following elements is:

Explain the following:

Group 17 elements are strong non-metals, while group 1 elements are strong metals.

Explain the following:

Metallic character of elements decreases from left to right in a period while it increases in moving down a group.

Explain the following:

Halogens have a high electron affinity.

Explain the following:

The reducing power of element increases down in the group while decreases in a period.

Why does the size of the atoms progressively become smaller when we move from sodium (Na) to chlorine (Cl) in the third period of the periodic table?

Name the periodic property which relates to the amount of energy required to remove an electron from an isolated gaseous atom.

Name the periodic property which relates to the character of element which loses one or more electrons when supplied with energy.

Name the periodic property which relates to the tendency of an atom to attract the shared pair of electron.

This question refers to the elements of the periodic table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these are most electronegative element?

This question refers to the elements of the periodic table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these is a halogen?

This question refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these is an alkali metal?

This question refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these is an element with valency 4?

This question refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these have least Ionisation Energy?

This question refers to the elements of the Periodic Table with atomic numbers from 3 to 18. Some of the elements are shown by letters, but the letters are not the usual symbols of the elements.

Which of these have least atomic size in period 3?

A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last). Answer the following question in relation to the given group of elements:

Which element has the most metallic character?

A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last). Answer the following question in relation to the given group of elements:

Which element would be expected to have the highest electronegativity?

A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last).

Boron, Aluminium, Gallium, Indium, Thallium

Answer the following question in relation to the above group of elements:

If the electronic configuration of aluminium is 2, 8, 3, how many electrons are there in the outer shell of thallium?

A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last).

Boron, Aluminium, Gallium, Indium, Thallium

Answer the following question in relation to the above group of elements:

The atomic number of boron is 5. Write the chemical formula of the compound formed when boron reacts with chlorine.

A group of elements in the periodic table is given below (Boron is the first member of the group and Thallium is the last).

Boron, Aluminium, Gallium, Indium, Thallium

Answer the following question in relation to the above group of elements:

Will the elements in the group to the right of this boron group be more metallic or less metallic in character? Justify your answer.

What is the significance of atomic numbers in the modern Periodic Table?

Arrange the following as per instruction given in the bracket.

Mg, Cl, Na, S, Si (decreasing order of atomic size)

Arrange the following as per instruction given in the bracket.

Cs, Na, Li, K, Rb (increasing metallic character)

Arrange the following as per instruction given in the bracket.

Na, Mg, Cl, S, Si (increasing ionisation potential)

Arrange the following as per instruction given in the bracket.

Cl, F, Br, I (increasing electron affinity)

Arrange the following as per instruction given in the bracket.

Cs, Na, Li, K, Rb (decreasing electronegativity)

Arrange the following as per instruction given in the bracket.

K, Pb, Ca, Zn (increasing reactivity)

Arrange the following as per instruction given in the bracket.

Li, K, Na, H (decreasing order of their potential ionisation)

Chlorine in the Periodic Table is surrounded by the elements with atomic number 9, 16, 18 and 35.

Which of these have Physical and Chemical properties resembling chlorine?

Chorine in the periodic table is surrounded by the elements with atomic number 9, 16, 18 and 35.

Which is more electronegative than chlorine?

First ionisation enthalpy of two elements X and Y are 500 kJ mol⁻¹ and 375 kJ mol⁻¹ respectively. Comment about their relative position in a group as well as in a period.

Arrange the following in order of increasing radii:

Cl⁻, Cl

Explain your choice.

Arrange the following in order of increasing radii:

Mg²⁺, Mg, Mg⁺

Explain your choice.

Arrange the following in order of increasing radii:

N, O, P

Explain your choice.

Arrange the following in order of increasing ionisation energy:

P, Na, Cl

Explain your choice.

Arrange the following in order of increasing ionisation energy:

F, O, Ne

Explain your choice.

Arrange the following in order of increasing ionisation energy:

Ne, He, Ar

Explain your choice.

Give reasons as to why the oxidising power of elements increases on moving from left to right along a period in periodic table.

Across a period, the ionization potential ______.

Down the group, electron affinity ______.

In the periodic table alkali metals are placed in the group ______.

Which of the following properties do not match with elements of the halogen family?

State the group and period, of the element having three shells with three electrons in valence shell.

The electronegativities (according to Pauling) of the elements in period 3 of the periodic table are as follows with elements arranged in alphabetical order:

Arrange the elements in the order in which they occur in the periodic table from left to right.

(The group 1 element first, followed by the group 2 element and so on, up to group 7).

The element below sodium in the same group would be expected to have a ______ (lower/higher) electro-negativity than sodium and the element above chlorine would be expected to have a ______ (lower/higher) ionization potential than chlorine.

On moving from left to right in a given period, the number of shells ______.

On moving down a group, the number of valence electrons ______.

Metals are good ______ because they are electron ______.

The change in the properties of elements on moving from left to right across a period of the periodic table. For the property, choose the correct answer.

The non-metallic character of the elements:

The changes in the properties of elements on moving from left to right across a period of the Periodic Table. For the property, choose the correct answer.

The electronegativity: 

The changes in the properties of elements on moving from left to right across a period of the Periodic Table. For the property, choose the correct answer. 

The ionization potential: 

The changes in the properties of elements on moving from left to right across a period of the Periodic Table. For the property, choose the correct answer. 

The atomic size:

The changes in the properties of elements on moving from left to right across a period of the Periodic Table. For the property, choose the correct answer. 

The electron affinity of elements in groups 1 to 7:

The elements of one short period of the periodic table are given below in order from left to right: 

To which period do these elements belong? 

The elements of one short period of the periodic table are given below in order from left to right: 

One element of this period is missing. Which is the missing element and where should it be placed? 

The elements of one short period of the periodic table are given below in order from left to right: 

Place the three elements fluorine, beryllium and nitrogen in the order of increasing electronegativity. 

The elements of one short period of the periodic table are given below in order from left to right: 

Which one of the above elements belongs to the halogen series?

With reference to the variation of properties in the Periodic Table, which of the following is generally true?

Atomic numbers of elements A, B, C, D, E, F are 8, 7, 11, 12, 13 and 9 respectively. State the type of ions they form. 

Formula of ion of A is A²⁺. Element A probably belongs to ______ group.

In a period, increase in electron affinity increases ______.

On descending a group, ______ in ionisation potential as well as electron affinity ______ oxidising capacity.