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Correct OPTION is (d) benzene

To ELABORATE: Natural gas is found along with petroleum below the surface of the earth, its composition is methane, HIGHER hydrocarbons, ethane and propane. It is used as a FUEL and its combustion is carbon black which is a reinforcing agent for RUBBER.

The correct answer is (d) zeolites

Best explanation: When aluminium IONS replace few ions in a three-dimensional NETWORK of silicon dioxide, the OVERALL structure is KNOWN as aluminosilicate and it also requires negative charge cations like sodium, POTASSIUM or calcium to balance negative charge. Few examples are zeolites and feldspar.

Correct choice is (a) TRUE

To explain I would say: Talc consists of PLANAR sheets which can slip over one another due to the WEAK FORCES of attraction and it is a constituent of talcum powder. That’s the reason why talcum powder has a slippery touch, So the above statement can be CONSIDERED to be true.

Correct choice is (b) silicones

The EXPLANATION: The linear, cyclic or cross-linked polymer compounds CONTAINING R2SiO, as a repeating unit, is known as Silicones. They are manufactured from alkyl substituted chlorosilanes they are chemically inert, WATER repellent and also HEAT resistant.

Right choice is (b) Carborundum

The explanation is: Carborundum is the second HARDEST material known and has a FORMULA of silicon carbide that is SiC. It is used as a semiconductor at high-temperature and ALSO in transistor diode RECTIFIERS. Diamond is the first hardest material known.

Right answer is (a) Be3Al2Si6O18

For explanation I would say: The chemical FORMULA of BERYL is given as Be3Al2Si6O18. Beryl is a type of cyclic silicate and it has TWO oxygen atoms shared and the basic UNIT is Si6O18^12-. It is known as beryllium aluminium cyclosilicate.

Right CHOICE is (c) liquefied petroleum GAS

Explanation: The full FORM of LPG is liquefied petroleum gas and its composition is N-butane and isobutene. It is used as a domestic fuel. LPG, that is liquefied petroleum gas is commonly used in household for cooking.

The correct answer is (d) SiO4^4-

The explanation is: SILICATES are the metal derivatives of silicic ACID, H2SiO3 and can be obtained by fusing metal oxides or metal carbonates with sand. The basic structural UNIT of silicates is SiO4^4-. An EXAMPLE is Zircon (ZrSiO4).

The correct option is (a) true

Best explanation: CARBON dioxide is given chemically by CO2 and it is a colourless and odourless GAS with water, it forms CARBONIC acid. The chemically balanced equation is given as H2CO3(aq) + H2O → HCO3^– + H3O^+.

Correct choice is (d) oxidising agent

The best explanation: Carbon monoxide is a colourless, odourless and almost water-insoluble gas. It is a POWERFUL reducing agent. It is also used in the extraction of many metals from their OXIDE ORES LIKE ferrous oxide and zinc oxide.

Right OPTION is (c) CARBON monoxide and nitrogen

The EXPLANATION: The mixture of carbon monoxide and nitrogen is known as producer gas and the mixture of carbon monoxide and hydrogen known as WATER gas. At 1273 K carbon combines with OXYGEN and nitrogen in order to form producer gas.

Right answer is (c) Graphite

The best I can EXPLAIN: Graphite is also a crystalline form of allotropic CARBON which is dark grey in color, it has hexagonal plates, the hybridization of carbon is sp^2 and it is a GOOD conductor of HEAT and electricity DUE to the presence of electrons. It is known as a black lead and it is also a very good lubricant.

Right answer is (a) carbon

To elaborate: WOOD CHARCOAL is obtained by heating wood strongly in the absence of air. When HEATED with steam, it becomes more activated and it is USED to remove coloring matters and audio odouiferous gases. It is an allotrope of carbon which is in AMORPHOUS form.

The correct option is (a) True

Explanation: Bone black or ANIMAL Charcoal is obtained by destructive DISTILLATION of bones in iron retort by-products are bone oil and pyridine. It is used as adsorbent on burning, it gives Bone ASH which is calcium phosphate and used in the manufacture of PHOSPHORUS and phosphoric acid.

The correct option is (d) Lampblack

For EXPLANATION: Diamond, fullerenes COME and GRAPHITE are crystalline allotropes of carbon whereas lampblack is an amorphous form of carbon, which is obtained by burning vegetable oils in a limited supply of air and it is ALSO used in the manufacture of printing ink, black PAINT, varnish, and carbon paper.

Right answer is (C) COAL

Explanation: The different types of coal are PEAT 60% of carbon, lignite 70% of carbon, bituminous 78% of carbon, semi-bituminous 83% of carbon and ANTHRACITE 90% of carbon. Among them, bituminous is the most common VARIETY of coal.

Right answer is (B) AQUA Dag

The EXPLANATION: Graphite is a form of crystalline allotropes of carbon the suspension of graphite in water is known as aqua dag and the suspension of graphite in oil LUBRICANTS is known as oil Dag. Aqua dag is commonly used in cathode RAY tubes.

Correct option is (d) C60

Easy explanation: A Fullerene is a CRYSTALLINE form of allotropic carbon, which is the only pure form of carbon. It is a C60 molecule which is used in MICROSCOPIC ball bearings, lightweight BATTERIES, in the SYNTHESIS of new plastics and new drugs.

Right OPTION is (C) 12

Explanation: The Fullerenes are C60 molecules which CONTAIN 12 five-membered rings and 20 SIX remembered rings, the five-membered rings are connected to six-membered rings while six-membered rings are connected to both five and six-membered rings.

Correct ANSWER is (C) +2, +4

Easiest explanation: The elements of carbon family exhibit + 2 and + 4 oxidation state. The compounds of PLUMBUM in + 4 oxidation state are powerful oxidizing agents since +2 oxidation state of plumbum is more stable DUE to inert pair EFFECT.

Right CHOICE is (b) CX4 > Si X4 > GE X4 > SN X4 > Pb X4

The explanation: All the elements of Carbon family give tetrahedral and covalent halides of the type MX4. The THERMAL stability follows in the decreasing order of CX4 > Si X4 > Ge X4 > Sn X4 > Pb X4 for the elements of group 14.

Right answer is (d) 2

To elaborate: The Carbon family can form two types of oxides, mono oxides of the type MO LIKE carbon monoxide and silicon monoxide which are all BASIC, it can also found the oxides of the type MO2 where carbon dioxide and silicon dioxide are ACIDIC and the dioxide of Germanium, silicon and plumber are amphoteric.

Correct ANSWER is (a) solid carbon dioxide

To ELABORATE: Carbon dioxide is LINEAR gas at ordinary temperature but at low temperatures, it is in solid form and also known as dry ICE or drikold. it is used for storing frozen substances at a LOWER temperature than normal water and it is used for cooling.

The correct choice is (d) SnCl2.5H2O

Easy explanation: The compound Stannous chloride with 5 moles of WATER is CALLED BITTER of TIN and it is used as a mordant in dyeing as it GIVES bright colours. Its chemical formula is given by SnCl2.5H2O and it is a white crystalline solid.

Right answer is (a) Yes

Explanation: Catenation is a TENDENCY of ELEMENTS to form long chains with repeated units of the same element. The greater the strength of element, the greater the strength of catenation. In the carbon family, the catenation strength is in the DECREASING order of carbon, silicon, germanium = stannum and PLUMBUM.

Correct choice is (d) light brown

Easiest explanation: ONE of the main general physical properties of GROUP 14 elements is their colour. The colour of CARBON is black, SILICON is light brown, germanium is greyish, stannum is silvery WHITE and plumbum is also silvery white in colour.

The correct choice is (c) OXIDATION State

Explanation: The Fajan’s rule is that the compounds in +2 oxidation state are ionic in nature and + 4 oxidation state is covalent in nature, THEREFORE the Fajan’s rule is about Oxidation state and their nature of the compounds.

Correct option is (a) true

The explanation is: In the case of carbon, 406 KJ per MOLE of ENERGY is required for promotion of 2s electron to 2p. The formation of two extra bonds provides this energy, therefore we can say that all the elements exhibit tetravalency in group 14. So the above statement is true.

Right OPTION is (c) covalent

Easiest explanation: All the MEMBERS of group 14 form covalent HYDRIDES, their NUMBER and EASE of formation decreases down the group along with their thermal stability while their reducing character increases down the group.

Correct option is (a) Yes

Best EXPLANATION: Yes, carbon forms pπ-pπ bonds with itself and with SULPHUR, nitrogen and oxygen other elements show the negligible tendency of this TYPE due to their larger size. Other elements FORM dπ-pπ MULTIPLE bonds.

The correct answer is (a) ALUMINIUM

Best EXPLANATION: The elements of Carbon family are the elements of group 14. They are carbon, Silicon, Germanium, STANNUM and PLUMBUM. Their valence shell configuration is ns^2np^2 and their VALENCY is four. But aluminium belongs to group 13.

The CORRECT CHOICE is (a) Stannum

Explanation: There are mainly five ELEMENTS in CARBON family; carbon, silicon, germanium, stannum and plumbum. The carbon and silicon are non-metals, germanium is a metalloid whereas stannum, plumbum are metals.

Right choice is (b) germanes

The explanation is: The HYDRIDES of carbon are called HYDROCARBONS ALKANES, ALKENES or alkynes, whereas the hydrides of silicon are called silanes and the hydrides of GERMANIUM are called Germanes the only hydrides of stannane and plumbum are stand and plumbane.

Right ANSWER is (b) FALSE

To explain I would say: Density INCREASES with increase in atomic number due to the increase in mass per unit volume down the group and the IONIZATION ENTHALPY decreases from carbon to stannum, for plumbum it is slightly higher than stannum. So the above statement is considered to be false.

Correct option is (a) covalent ALUM

To elaborate: K2SO4.Al2(SO4)3.24H2O, Na2SO4.Al2(SO4)3.24H2O, (NH4)2SO4.Al2(SO4)3.24H2O and (NH4)2SO4.Fe2(SO4)3.24H2O are RESPECTIVE chemical FORMULAE of Potash alum, sodium alum, AMMONIUM alum and FERRIC alum.

Correct choice is (a) true

To elaborate: The term ALUM is given to double sulphates of the type X2SO4.Y2(SO4)3.24H2O where, X REPRESENTS a monovalent cation such as sodium ion, potassium ion and ammonium while why is a trivalent cation such as aluminium 3 +, chromium 3 +, ferrous 3 + and Cobalt 3 +. Lithium-ion does not FORM alum.

Right answer is (b) alumina

To explain I would SAY: Alumina is also KNOWN as aluminium oxide and it is the most stable compound of aluminium that OCCURS in nature as colourless corundum and several coloured OXIDES, like ruby, topaz, sapphire, and emerald, these are USED as precious stones.

Correct option is (b) Al2O3, AlCl3

Easy explanation: The chemical formula of alumina is Al2O3 and that of ANHYDROUS aluminium CHLORIDE is AlCl3. Alumina is nothing but aluminium oxide. Anhydrous aluminium chloride is PREPARED by heating a mixture of alumina and carbon in a current of dry CHLORINE.

Right choice is (c) anhydrous aluminium chloride

For EXPLANATION I would say: Friedel CRAFTS reactions are the reactions in which substituents are added to the AROMATIC rings. There are two types of friedel craft reactions namely alkylation and acylation. Anhydrous aluminium chloride is used as a catalyst in these Friedel craft reactions.

The CORRECT choice is (b) semiconductor

Easiest explanation: Yes, Boron is used as a semiconductor and also Boron Steel rods are used for controlling the nuclear REACTIONS. Boron is used as a DOPANT for semiconductors such as SILICON and Germanium. Pure Boron is a BLACK, lustrous semiconductor.

Correct option is (a) painting

For explanation: Orthoboric acid which is GIVEN by the chemical formula H3BO3 is used as an antiseptic and eye lotion under the NAME boric lotion and it is also used as a food preservative. The boric lotion is a saturated solution of 4% boric acid in WATER.

Correct option is (a) SILVER paints

Explanation: There are MANY applications of boron like heat resistant glasses, glass wool, fibreglass, flux for soldering metals, for heat, scratch and stain resistant glazed coating to earth and wears and as a constituent of medical soaps. It is also used and the making of Boron fibres, bulletproof VEST making and also and nuclear reactions in ORDER to absorb neutrons.

Correct answer is (d) Aluminium sulphate

The explanation: Aluminium sulphate which is given by the chemical formula Al2(SO4)3 is used for MAKING fireproof clothes and it is also used as a fire fighting foam. Aluminium sulphate is also used as an ANTISEPTIC, ASTRINGENT and also as a MODERN in dyeing textiles.

Right choice is (b) a mixture of aluminium POWDER with ammonium nitrate

Explanation: A mixture of aluminium powder with ammonium nitrate is called ammonal and is used in bombs with a ratio of 5:95. Here the aluminium ACTS as a fuel and ammonium nitrate as an OXIDIZER, it was first used in the YEAR 1916 by the britishers near MINES.

The correct choice is (a) YES

Best EXPLANATION: Yes, inorganic benzene is more reactive than Benzene. The FORMULA for inorganic benzene is given by B3N3H6 and it is otherwise KNOWN as borazine or BORAZOLE. The pair of electrons and borazine are only partially localized, therefore we can say that it is more reactive than Benzene.

Right option is (d) Borazole

The EXPLANATION: Borazole, borazine and inorganic BENZENE are same and their chemical formula is GIVEN by B3N3H6, it is a colourless liquid having a six-membered ring of alternating Boron and NITROGEN atoms (the reason why it’s called inorganic benzene).