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Q1. The shape of Buckminsterfullerene is like a:

• Tennis ball
• Soccer ball
• Cricket ball
• Rugby ball

Solution

The shape of Buckminsterfullerene is like a soccer ball.

Q2. The reaction of aluminium with acids and alkalis shows that:

• It is acidic in nature.
• It is basic in nature.
• It is amphoteric in nature.
• It is inert towards acids and alkalis.

Solution

Aluminium dissolves in mineral acids and aqueous alkalis and produces dihydrogen, thus shows amphoteric character.   2Al_(s) + 6HCl _(aq) → 2Al³⁺ _(aq) + 6Cl^- _(aq) + 3H_{2 (g)} 2Al _(s) + 2NaOH(aq) + 6H₂O_(l)  2 Na⁺ [Al(OH)₄]^- _(aq) + 3H_2(g)                                                                Sodium                                                            tetrahydroxoaluminate(III)

Q3. Which of the following element forms M³⁺ more easily among group 13 elements?

• B
• Al
• Ga
• Tl

Solution

B generally forms covalent compounds due to higher ionisation enthalpy. Other elements except Al predominantly forms M⁺ ion instead of M³⁺ due to inert pair effect. Hence Al forms Al³⁺ more easily among group 13 elements.

Q4. Catenation is self linking property of:

• Carbon
• Sodium
• Germanium
• Lead

Solution

The self linking property of carbon is known as catenation.

Q5. Pick out the odd one out from the following.

• Bauxite
• Quartz
• Cristobalite
• Tridymite

Solution

Bauxite is the compound of Aluminium rest Quartz, cristobalite and tridymite are some of the crystalline forms of silica.

Q6. Which of the  oxide is  acidic from the following ?

• _CO
• _SnO
• PbO
• _GeO

Solution

CO is neutral, GeO is distinctly acidic whereas SnO and PbO are amphoteric.

Q7. When orthoboric acid is strongly heated it  leaves a residue of:

• Metaboric acid
• Tetraboric acid
• Boric anhydride
• Boron

Solution

On heating, orthoboric acid above 370K forms metaboric acid, HBO₂ which on further heating yields boric anhydride, B₂O₃. H₃BO₃  HBO₂  B₂O₃

Q8. Boron reacts with Chlorine to give:

• BCl₃
• BCl₅
• BCl
• BCl₆

Solution

The elements of group 13 react with halogens to form trihalides.    2E_(s) + 3 X_{2 (g)} →2EX_{3 (s)}                              (X = F, Cl, Br, I) Where, E is the group 13 element.

Q9. Boron generally forms:

• Electron-deficient compound
• Electron rich compound
• Electron precise compound
• Does not form any compound at all

Solution

Boron generally forms electron deficient compound in which it lacks one electron pair to complete it octet and acts as Lewis acid.

Q10. The oxidation state which is not exhibited by group 18 elements is:

• +2
• +3
• +4
• +6

Solution

Group 18 elements exhibit only +2,+4 and +6 oxidation states.

Q11. The general electronic configuration of p-block elements is:

• ns²np^1-6
• ns¹np^1-5
• np⁵
• ns^onp^1-6

Solution

The general electronic configuration of p-block elements is ns²np^1-6.

Q12. Silicon dioxide is commonly known as:

• Silica
• Silicates
• Silloids
• None of these

Solution

Silicon dioxide is commonly known as silica.

Q13. Germanium is transparent in:

• Infrared region
• Ultraviolet region
• Microwave region
• Visible region

Solution

Infrared region

Q14. The chemical formula of Cryolite, an important mineral of aluminium is:

• Na₃AlF₆
• Al₂O₃.2H₂O
• Al₂O₆
• AlCl₃.H₂O

Solution

Cryolite is Na₃AlF₆.

Q15. Boric acid has a layer structure in which planar BO₃  units are joined by:

• O-bonds
• N-bonds
• H-bonds
• Na-bonds

Solution

Q16. Which of the following has covalent radius more than germanium?

• C
• Si
• Sn
• B

Solution

Sn and Pb have covalent radius more than germanium.

Q17. The nature of B₂O₃ is:

• Acidic
• Basic
• Amphoteric
• Neutral

Solution

Boron forms acidic oxide.

Q18. Water gas is a mixture of hydrogen and:

• Sulphur dioxide
• Carbon monoxide
• Carbon dioxide
• Nitrogen trioxide

Solution

Water gas is a mixture of hydrogen and carbon monoxide.

Q19. The element that shows anomalous behaviour in group 13

• Boron
• Aluminium
• Gallium
• Thallium

Solution

Boron shows anomalous behaviour in group 13 because of its small size and absence of d orbital.

Q20. Which of the following statements is true?

• The atomic radius of Ga is more than Al.
• The atomic radius of Ga is less than Al.
• The atomic radius of Ga is equal to Al.
• The atomic radius of Ga is less than B.

Solution

The presence of additional 10 d-electrons offer only poor screening effect for the outer electrons from the increased nuclear charge in gallium hence the atomic radius of Ga is less than Al.

Q21. Pick out the odd man out from the following.

• Asbestos
• Mica
• Zeolites
• Quartz

Solution

Feldspar, zeolites, mica and asbestos are all silicates minerals except quartz.

Q22. The hybridization state of Carbon in fullerene is:

• sp²
• sp³
• sp
• None of these

Solution

The hybridization state of carbon in fullerene is sp² in which each carbon atom forms three sigma bonds with three other carbon atoms.

Q23. The hybridization involved in BCl₃NH₃ is:

• sp
• sp³
• sp³d
• sp³d²

Solution

The central atom B in BCl₃NH₃, forms four sigma bond  hence the  hybridization is sp³.

Q24. Boron has high melting point because:

• It is the first element in the group.
• It has strong crystalline lattice.
• It has no d orbital.
• It forms strong ionic bond.

Solution

Boron has high melting point because it has strong crystalline lattice.

Q25. Which of the following does not react directly with halogens to form halides?

• Si
• C
• Ge
• Sn

Solution

Except carbon, all other members react directly with halogens to form halides.

Q26. Percentage of lead in lead pencils is:

• Zero
• 40
• 50
• 60

Solution

There is no percentage of lead in lead pencils.

Q27. The formula of inorganic benzene is:

• B₃N₃H₆
• B₆H₆
• N₆H₆
• B₃C₃H₆

Solution

Reaction of ammonia with diborane gives initially B₂H_6.2NH₃ which is formulated as [BH₂(NH₃)₂]⁺ [BH₄]^- ; further heating gives borazine, B₃N₃H₆ known as inorganic benzene.

Q28. Which of the following oxides has a three dimensional structure?

• CO
• CO₂
• SiO₂
• SO₂

Solution

Silicon dioxide is a covalent, network solid in which each silicon atom is tetrahedrally surrounded by 4 oxygen atoms.

Q29. What is the valence shell electronic configuration of group 14 elements?

• ns²np²
• ns²np⁴
• ns¹np⁴
• ns²np⁶

Solution

The group 14 elements have 2 electrons in the valence shell.

Q30. The hybridization state of carbon in carbon dioxide is:

• sp
• sp²
• sp³
• None of these

Solution

The hybridization state of carbon in carbon dioxide is sp. Two sp hybridized orbitals of carbon atom overlap with two p orbitals of oxygen atom to form 2 sigma bond while other two electrons of carbon are involved in pπ-pπ bonding with oxygen atom.    

Q31. Which one of the following is not an allotrope of carbon?

• Diamond
• Graphite
• Butane
• Fullerene

Solution

The various physical forms in which an element can exist are called allotropes of the element. Butane is a compound.

Q32. The first member of p-block differs from remaining members of corresponding group because of:

• Its small size
• Absence of d orbital
• Absence of f orbital
• Both A & B

Solution

The first member of p-block differs from remaining members of corresponding group because of its small size and absence of d orbital.

Q33. Which of the following statement is not true about boric acid?

• It is a strong dibasic acid.
• It is monobasic acid.
• It is a weak acid.
• It acts as Lewis acid.

Solution

Boric acid is a weak monobasic acid. It is not a protonic acid but acts as a Lewis acid by accepting electrons from a hydroxyl ion.

Q34. Amorphous boron on heating in air and with nitrogen produces:

• Oxide B₂O₃ and nitride BN
• Oxide BO₂ and nitride B₂N₆
• Oxide B₂O₆ and nitride BN
• Oxide B₂O₃ and nitride BN₃

Solution

The element E of group 13 forms oxide and nitride on heating in air as follows:   2E_(s) + 3O_2(g)  2E₂O_3(s) 2E_(s) + N_2(g)    2EN_(s)

Q35. The number of groups that belong to p-block are:

• 8
• 2
• 6
• 4

Solution

The maximum number of electrons that can be accommodated in a set of p orbitals is six. Consequently there are six groups of p-block elements in the periodic table.

Q36. Boric acid is prepared from borax by the action of:

• Hydrochloric acid
• Sodium hydroxide
• Carbon dioxide
• Sodium carbonate

Solution

 Na₂B₄O₇ + 2HCl + 5H₂O → 2NaCl + 4B(OH)₃                                                                                    Boric acid

Q37. Silicon shows diagonal relationship with:

• C
• Be
• Al
• B

Solution

Silicon shows similar properties as boron.

Q38. The group of organo silicon polymers, which have ( -R₂SiO-) as a repeating unit are known as:

• Silicones
• Quartz
• Cristobalite
• Tridymite

Solution

Silicones are a group of organo silicon polymers, which have (-R₂SiO-) as a repeating unit.

Q39. The zeolites which  are used as ion exchangers in softening of "hard" water are:

• Hydrated zeolites
• ZSM-5
• Feldspar
• Mica

Solution

Hydrated zeolites are used as ion exchangers in softening of "hard" water.

Q40. Carbon cannot expand its covalence beyond:

• 4
• 5
• 3
• 6