Important 1mark -chapter 3,4

Download Tamil Nadu 11th Standard Chemistry question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.

Questions:

Multiple Choice Question

50 x 1 = 50

Assertion: Helium has the highest value of ionisation energy among all the elements known
Reason: Helium has the highest value of electron affinity among all the elements known

(a)

Both assertion and reason are true and reason is correct explanation for the assertion

(b)

Both assertion and reason are true but the reason is not the correct explanation for the assertion

(c)

Assertion is true and the reason is false

(d)

Both assertion and the reason are false

Statement-I: Hydrogen can be used as a clean burning fuel.
Statement-II: Hydrogen on combustion give only water as end product and it is free from pollutants.

(a)

Statements-I and II are correct and Statement-II is the correct explanation of statement-I.

(b)

Statements-land II are correct but Statement-II is not the correct explanation of statement-I.

(c)

Statement-I is correct but Statement-II is wrong.

(d)

Statement-l is wrong but Statement-II is correct.

Statement-I: Heavy water has been widely used as moderator in nuclear reactors.
Statement-II: Heavy water can lower the energies of fast moving neutrons.

(a)

Statements-I and II are correct and Statement-II is the correct explanation of statement-I.

(b)

Statements-land II are correct but Statement-II is not the correct explanation of statement-I.

(c)

Statement-I is correct but Statement-II is wrong.

(d)

Statement-I is wrong but Statement-II is correct.

Statement-I: Hydrogen is placed at the top of the group which is in-line with the latest periodic table.
Statement-II: Hydrogen has a tendency to lose its electron to form H+, thus showing electropositive character like alkali metals. On the other hand, hydrogen has a tendency to gain an electron to yield H^-, thus showing an electronegative character like halogens.

(a)

Statements-I and II are correct and Statement-Il is the correct explanation of statement-I.

(b)

Statements-land II are correct but Statement-II is not the correct explanation of statement- I.

(c)

Statement-I is correct but Statement-II is wrong.

(d)

Statement-I is wrong but Statement-II is correct.

Assertion: Permanent hardness of water is removed by treatment with washing soda.
Reason: Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates

(a)

Both assertion and reason are true and reason is the correct explanation of assertion.

(b)

Both assertion and reason are true but reason is not the correct explanation of assertion.

(c)

Assertion is true but reason is false

(d)

Both assertion and reason are false

Statement- I: Ionization enthalpy of Be is greater than that of B.
Statement- II: The nuclear charge of B is greater than that of Be.

(a)

Statement-I and II are correct and statement-II is the correct explanation of statement-I.

(b)

Statement-I and statement-II are correct but statement-II is not the correct explanation of statement-I.

(c)

Statement-I is correct but statement-II is wrong.

(d)

Statement-I is wrong but statement-II is correct.

Choose the correct order of ionization energy.

(a)

N>O>F

(b)

F>O>N

(c)

N>O

(d)

O>F>N

Which of the following possess almost same properties due to lanthanide contraction?

(a)

Zr,HF

(b)

Na,K

(c)

Zn,Cd

(d)

Ag,Au

Which of the following is the correct electronic configuration of noble gases?

(a)

ns² np⁶ nd¹⁰

(b)

ns² np⁵

(c)

ns² np⁶

(d)

ns² np³

10.

Which one of the following is a metalloid?

(a)

(b)

(c)

(d)

11.

Which one of the following is called halogen family?

(a)

Group 17

(b)

Group 16

(c)

Group 1

(d)

Group 2

12.

Hydrogen resembles halogens in many respects for which several factors are responsible. Of the following factors which one is most important in this respect?

(a)

Its tendency to lose an electron to form a cation

(b)

Its tendency to gain an electron to attain stable electronic configuration.

(c)

Its low negative electron gain enthalpy value

(d)

Its small size

13.

Which of the following is the correct order of stability of bonds?

(a)

Hydrogen bond < Covalent bond < Vanderwaals bond

(b)

Vanderwaals bond < Hydrogen bond < Covalent bond

(c)

Vanderwaals bond> Hydrogen bond> Covalent bond

(d)

Covalent bond < Hydrogen bond < Vanderwaals bond

14.

Which period mostly include man made radioactive elements?

(a)

4^th period

(b)

7^th period

(c)

6^th period

(d)

3^rd period

15.

Match the list-land list-II using the correct code given below the list.

	List-I		List-II
A.	Z = 100	1.	Mendelevium
B	Z = 101	2.	Lawrencium
C.	Z = 102	3.	Fermium
D.	Z = 103	4.	Nobelium

(a)

A	B	C	D
4	3	2	1

(b)

A	B	C	D
3	1	4	2

(c)

A	B	C	D
4	1	3	2

(d)

A	B	C	D
3	2	1	4

16.

Which type of hydrides are generally non-stoichiometric in nature?

(a)

Metallic hydride

(b)

Covalent hydrides

(c)

Ionic hydride

(d)

Saline hydride

17.

Which one of the following is a universal solvent?

(a)

Alcohol

(b)

Ether

(c)

CCl₄

(d)

Water

18.

Which one of the following is used to study the movements of ground water?

(a)

Deuterium

(b)

Protium

(c)

Tritium

(d)

19.

The first ionisation potential (in eV) of Be and B respectively are ____________

(a)

8.29,9.32

(b)

9.32, 8.29

(c)

9.32, 9.32

(d)

8.29, 8.29

20.

The ionisation potential of Na is 5.48 eV. The ionisation potential of K will be __________

(a)

tho same as Na

(b)

4.34 eV

(c)

5.68 eV

(d)

10.88 eV

21.

Bond angles in H -O-Hand H -O-Oin water and H₂O₂ respectively are __________

(a)

104° 5',104° 5'

(b)

94.8°, 94.8°

(c)

104° 5', 94.8°

(d)

94.8°,104.5°

22.

Choose the correct statement with regard to ortho and para hydrogen.
1. Both have similar chemical properties but differ in some physical properties.
2. The boiling points of normal, ortho and para hydrogens are the same.
3. The nuclear spin in both forms are the same.
4. Para hydrogen has zero magnetic moment.

(a)

1,2

(b)

1,4

(c)

2, 3

(d)

2, 4

23.

The elements having highest ionization energies within their periods are called _____

(a)

Halogens

(b)

Noble gases

(c)

Alkali metals

(d)

Transition elements

24.

H₂O andH₂O₂ resemble in _____________

(a)

Bond angle

(b)

Hybridization of oxygen

(c)

Structure

(d)

Oxidation state of oxygen

25.

HF has ______ hydrogen bond.

(a)

intramolecular

(b)

intermolecular

(c)

intrastellar

(d)

interstellar

26.

H₂O₂ acts a ______ agent.

(a)

oxidizing

(b)

reducing

(c)

both reducing and oxidizing

(d)

neither reducing nor oxidizing

27.

Which one among the following exhibits a valency greater than 4?

(a)

(b)

(c)

(d)

28.

Match the list I with list II and select the correct answer using the code given below the list.

List I		List II
A	Unnilbium/td>	1	Bohrium
B	Unnilhexium	2	Roentgenium
C	Ununnunium	3	Seaborgium
D	Unnilseptium	4	Nobelium

(a)

A	B	C	D
1	2	4	3

(b)

A	B	C	D
3	1	4	2

(c)

A	B	C	D
4	3	2	1

(d)

A	B	C	D
4	3	1	2

29.

The structure of water molecule is __________

(a)

bent

(b)

tetrahedral

(c)

distorted octahedral

(d)

trigonal bi pyramidal

30.

Consider the following statements
1. Hard water forms scum with soap.
2. Hard water lathers easily with soap
3. Hard water is unsuitable for laundry and boilers
Which of the following statement(s) given above is are correct?

(a)

1 & 3

(b)

only 1

(c)

2 & 3

(d)

only 2

31.

The elements at the extreme left of periodic table has strong behaviour ______

(a)

Oxidizing

(b)

Reducing

(c)

both oxidisation and reducing

(d)

electro negative

32.

There are _____ periods in the periodic table.

(a)

(b)

(c)

(d)

33.

Hydrogen burns in air with a - flame.

(a)

light bluish

(b)

yellow

(c)

green

(d)

none of these

34.

The conversion of atomic hydrogen to dihydrogen is a __________ change.

(a)

endothermic

(b)

exothermic

(c)

photochemical

(d)

nuclear

35.

How does electron affinity change when we move from left to right in a period in the periodic table?

(a)

Generally increases

(b)

Generally decreases

(c)

Remains unchanged

(d)

First increases and then decreases

36.

Which one of the following is true about metallic character when we move from left to right in a period and top to bottom in a group?

(a)

Decreases in a period and increases along the group

(b)

Increases in a period and decreases in a group

(c)

Increases both in the period and the group

(d)

Decreases both in the period and in the group

37.

Which of the following is second most electronegative element?

(a)

Chlorine

(b)

Fluorine

(c)

Oxygen

(d)

Sulphur

38.

The element with positive electron gain enthalpy is

(a)

Hydrogen

(b)

Sodium

(c)

Argon

(d)

Fluorine

39.

Water is a ___________

(a)

basic oxide

(b)

acidic oxide

(c)

amphoteric oxide

(d)

none of these

40.

Volume strength of 1.5 N H₂O₂ is _____________

(a)

1.5

(b)

4.5

(c)

16.8

(d)

8.4

41.

A commercial sample of hydrogen peroxide marked as 100 volume H₂O₂, it means that _____________

(a)

1 ml of H₂O₂ will give 100 ml O₂ at STP

(b)

1 L of H₂O₂ will give 100 ml O₂ at STP

(c)

1 L of H₂O₂ will give 22.4 L O₂

(d)

1 ml of H₂O₂ will give 1 mole of O₂ at STP

42.

Zeolite used to soften hardness of water is hydrated _____________

(a)

Sodium aluminium silicate

(b)

Calcium aluminium silicate

(c)

Zinc aluminium borate

(d)

Lithium aluminium hydride

43.

The cause of permanent hardness of water is due to _____________

(a)

Ca(HCO₃)₂

(b)

Mg(HCO₃)₂

(c)

CaCl₂

(d)

MgCO₃

44.

Tritium nucleus contains _____________

(a)

1 p+0 n

(b)

2 p+1 n

(c)

1 p + 2 n

(d)

none of these

45.

Which of the following statements about hydrogen is incorrect?

(a)

Hydrogen ion, H₃O⁺ exists freely in solution.

(b)

Dihydrogen acts as a reducing agent.

(c)

Hydrogen has three isotopes of which tritium is the most common.

(d)

Hydrogen never acts as cation in ionic salts.

46.

Which one of the following arrangements represent the correct order of least negative to most negative electron gain enthalpy

(a)

Al < O < C < Ca < F

(b)

Al < Ca < O < C

(c)

C < F < O < Al < Ca

(d)

Ca < Al < C < O < F

47.

Identify the wrong statement.

(a)

Amongst the isoelectronic species, smaller the positive charge on cation, smaller is the ionic radius

(b)

Amongst isoelectric species greater the negative charge on the anion, larger is the ionic radius

(c)

Atomic radius of the elements increases as one moves down the first group of the periodic table

(d)

Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table

48.

In the third period the first ionization potential is of the order

(a)

Na > Al > Mg > Si > P

(b)

Na< Al < Mg < Si < P

(c)

Mg > Na > Si > P > Al

(d)

Na < Al < Mg < Si < P

49.

Various successive ionisation enthalpies (in kJ mol^-1) of an element are given below.

IE₁	IE₂	IE₃	IE₄	IE₅
577.5	1,810	2,750	11,580	14,820

The element is

(a)

phosphorus

(b)

Sodium

(c)

Aluminium

(d)

Silicon

50.

The electronic configuration of the elements A and B are 1s², 2s ²,2p⁶,3s² and 1s², 2s²,2p⁵ respectively. The formula of the ionic compound that can be formed between these elements is ___________

(a)

(b)

AB₂

(c)

A₂B

(d)

none of the above