chemistry MCQs - 9th class Chapter 08 Mcqs

1

The modern periodic table is based on the arrangement of elements according to increasing what?

A

Atomic Mass

B

Atomic Number

C

Number of Neutrons

D

Density

2

The horizontal rows of elements in the periodic table are called?

A

Groups

B

Blocks

C

Periods

D

Families

3

The vertical columns in the periodic table are called?

A

Periods

B

Series

C

Rows

D

Groups

4

Elements in a group show similar chemical properties because they have similar what?

A

Atomic sizes

B

Number of protons

C

Electronic configurations in their outermost shells

D

Melting points

5

How many periods are there in the modern periodic table?

A

18

B

10

C

7

D

14

6

Each period, except the first, starts with an alkali metal and ends at a what?

A

Halogen

B

Transition metal

C

Noble gas

D

Alkaline earth metal

7

The first period contains how many elements?

A

2

B

8

C

18

D

32

8

The 6th period in the periodic table is known as a?

A

Normal period

B

Short period

C

Long period

D

Very long period

9

The series of fourteen elements that starts after Lanthanum (La=57) is called?

A

Actinides

B

Lanthanides

C

Transition metals

D

Noble gases

10

The Lanthanide and Actinide series are jointly known as?

A

s-block elements

B

p-block elements

C

d-block elements

D

f-block elements

11

How many groups are there in total in the modern periodic table?

A

7

B

14

C

18

D

32

12

Elements in groups 1 and 2 are called what type of elements?

A

p-block elements

B

s-block elements

C

d-block elements

D

f-block elements

13

Elements in groups 13 to 18 are called what type of elements?

A

p-block elements

B

s-block elements

C

d-block elements

D

f-block elements

14

The elements in groups 3 to 12 are called what?

A

Normal elements

B

Alkali metals

C

Transition elements

D

Halogens

15

What is the family name for Group 1 elements?

A

Halogens

B

Noble Gases

C

Alkaline earth metals

D

Alkali metals

16

What is the family name for Group 2 elements?

A

Alkali metals

B

Alkaline earth metals

C

Boron family

D

Carbon family

17

What is the family name for Group 17 elements?

A

Halogen family

B

Noble gases

C

Oxygen family

D

Nitrogen family

18

What is the family name for Group 18 elements?

A

Alkali metals

B

Alkaline earth metals

C

Halogen family

D

Noble gases

19

All elements of group 1 have how many electrons in their outermost shell?

A

1

B

2

C

7

D

8

20

The reactivity of alkali metals does what as you go down the group?

A

Decreases

B

Increases

C

Stays the same

D

Becomes zero

21

Group 2 elements show a tendency to lose how many of their outermost electrons?

A

1

B

2

C

3

D

4

22

Group 17 elements have what electron configuration in their outer shell?

A

s²p⁴

B

s²p³

C

s²p⁵

D

s²p⁶

23

Group 17 elements are also called halogens, which means?

A

Gas forming

B

Salt forming

C

Water forming

D

Acid forming

24

Unlike alkali metals, the reactivity of halogens does what down the group?

A

Increases

B

Remains constant

C

Decreases

D

Doubles

25

Group 1 elements tend to form cations with what charge?

A

+1

B

+2

C

-1

D

-2

26

Atomic radius is defined as half the distance between the nuclei of two what?

A

Opposite ions

B

Identical bonded atoms

C

Adjacent atoms in a crystal

D

Different atoms in a molecule

27

What is the unit for atomic radius mentioned in the text?

A

nm

B

cm

C

pm

D

mm

28

How does the atomic radius generally change when we move from left to right in a period?

A

Increases

B

Decreases

C

Stays constant

D

First increases, then decreases

29

Why does the size of atoms decrease from left to right in a period?

A

Addition of a new shell

B

Decrease in nuclear charge

C

Increase in nuclear charge pulls electrons closer

D

Increase in shielding effect

30

How does the atomic radii of atoms change from top to bottom in a group?

A

Decreases

B

Remains the same

C

Increases

D

First decreases, then increases

31

What is ionization energy?

A

Energy released when an electron is added

B

Energy required to remove the most loosely bound electron

C

Energy to break a chemical bond

D

Energy to form a crystal lattice

32

The first ionization energy of sodium atom is?

A

+496 kJ mol⁻¹

B

+737 kJ mol⁻¹

C

-328 kJ mol⁻¹

D

+1450 kJ mol⁻¹

33

How does ionization energy change from left to right in a period?

A

Decreases

B

Increases

C

Does not change

D

Becomes zero

34

How does ionization energy change from top to bottom in a group?

A

Increases

B

Decreases

C

Does not change

D

Doubles with each element

35

What is electron affinity?

A

Energy required to remove an electron

B

Energy released when an electron is added

C

The ability to form a positive ion

D

The ability to form a covalent bond

36

How do electron affinity values generally change from top to bottom in a group?

A

Increase

B

Decrease

C

Remain constant

D

Become positive

37

What is electronegativity?

A

The force to remove an electron

B

The energy released when gaining an electron

C

The force with which an atom attracts a shared pair of electrons

D

The measure of an atom's size

38

Which of the following is the most electronegative atom?

A

Sodium (Na)

B

Fluorine (F)

C

Cesium (Cs)

D

Lithium (Li)

39

How does electronegativity change from left to right in a period?

A

Decreases

B

Stays the same

C

Increases

D

Becomes zero

40

The tendency of an element to lose electrons and form positive ions is called?

A

Electronegativity

B

Electron affinity

C

Metallic character

D

Non-metallic character

41

How does metallic character change down a group?

A

Decreases

B

Increases

C

Remains the same

D

Becomes non-metallic

42

How does metallic character change in a period from left to right?

A

Increases

B

Decreases

C

Stays the same

D

Becomes more metallic

43

What happens to the chemical reactivity as we move from left to right in a period?

A

Gradually increases

B

Gradually decreases then increases

C

Stays constant

D

Sharply increases

44

How does the density of elements generally change from top to bottom in a group?

A

Decreases

B

Varies unpredictably

C

Increases

D

Stays the same

45

The electronic configuration of the outermost shell of a transition metal is typically?

A

ns²np⁶

B

ns²np⁴

C

ndx ns²

D

ns¹

46

An element in the 6th group which is a gas belongs to which period?

A

2nd period

B

3rd period

C

4th period

D

5th period

47

An element with eight electrons in its outermost shell is what type of element?

A

Alkali metal

B

Halogen

C

Noble gas

D

Transition metal

48

Oxides of Group 1 metals (alkali metals) are what in nature?

A

Acidic

B

Basic

C

Neutral

D

Amphoteric

49

The distance between the nuclei of two bonded carbon atoms is 154 pm. What is the radius of a carbon atom?

A

154 pm

B

308 pm

C

77 pm

D

100 pm