| Most abundant element in universe constitutes .... % of mass of the universe. | HYDROGEN, 70% |
| TRITIUM is radioactive and emits low energy .... particles, with half life ..... years | BETA, 12.33 |
| The predominant isotope of hydrogen is.... | PROTIUM |
| Hydrogen is .... most abundant on the surface of the globe. | THIRD |
| Methods for laboratory prep. of Dihydrogen (2) | 1) Rxn of zinc with dil. HCl
2) Rxn Zn with aq. alkali |
| Water gas consists of ... and ... | CO and H2 |
| Water gas used in synthesis of .... | METHANOL and hydrocarbons |
| ISOTOPES have same chemical properties but differ RATES of reaction due to ... | different enthalpy of bond dissociation |
| physical prop of H isotopes differ due to | large mass differences |
| Producing .... from coal is called Coal gasificaton | Syn gas |
| WATER GAS SHIFT REACTION catalyst? | IRON (3) CHROMATE |
| IN water gas shift rexn CO2 is removed by scrubbing with .... soln | SODIUM ARSENITE |
| DIHYDROGEN IS | COLORLESS |
| ...-... BOND ENTHALPY is the highest for a single bond bn two atoms of any element? | H-H |
| Atomic H is produced at a high temp. in an ...arc or under ...radiations | electric/UV |
| Hydrogenation of vegetable oils using ... as catalyst gives edible fat oils like...&... | NICKEL, MARGARINE/VANASPATI GHEE |
| ... of OLEFINS yields aldehydes which further undergo ... to give ALCHOHOLS | HYDROFORMYLATION, REDUCTION |
| In METALLURGICAL PROCESSES, dihydrogen is used to ... | REDUCE HEAVY METAL OXIDES TO METALS |
| ...HYDROGEN & ...HYDROGEN TORCHES find use in ...&... | Atomic & oxy-
CUTTING / WELDING |
| HYDROGEN combines with almost all elements except ... to form BINARY compounds called ... | noble gases, hydrides |
| Three categories of Hydrides | IONIC/ COVALENT/ METALLIC |
| SALINE/ SALTLIKE HALIDE | IONIC HALIDE |
| MOLECULAR HYDRIDE | COVALENT HYDRIDE |
| NON STOICHIOMETRIC HALIDES | METALLIC HALIDES |
| CO(g) + 2H2(g) ---> | CH3OH(l) |
| hydrides_ LAW of constant composition doesn't hold good | NON STOICHIOMETRIC HYDRITES |
| MOLECULAR HYDRITES types(3) | 1)E- DEFICIENT
2) E- PRECISE
3) E- RICH |
| COVALENT HYDRITES (volatile/not) | VOLATILE |
| POLYMERIC metal hydrites | BeH2 / MgH2 |
| STOICHIOMETRIC HYDRITES (ionic/covalent/metallic) | IONIC and COVALENT |
| ... is unreactive with O2 and Cl2 at moderate temperatures | lithium hydride |
| All elements of group... will form E- rich hydrides | 15-17 |
| INERSTITIAL HYDRIDES | METALLIC HYDRIDES |
| UNUSUAL PROPERTIES OF WATER IN THE CONDENSED PHASE | EXTENSIVE HYDROGEN BONDING |
| Ni/Pd/Ce/ Ac | EXCEPT hydrides of .../.../.../... other METALLIC hydrites have lattice different from parent metals |
| All hydrides of group ... are E- deficient | 13 |
| hydrogen STORAGE (metals used) | Pd/Pt
CAN ACCOMODATE LARGE NO OF HYDROGEN |
| Property of H used in CATALYTIC reduction/hydrogenation | prop: ABSORPTION OF H ON TRANSITION METALS |
| WHY water has high freezing pt, boiling pt, heat of fusion incomparision to H2S & H2Se | HYDROGEN BONDING |
| ELECTRON PRECISE HYDRITES_group | gp 14 eg CH4 |
| WHICH hydrite is used in synthesis of other hydrides | LITHIUM |
| WHY even COVALENT COMPOUNDS like Alchohol and Carbohydrates dissolve in water? | due to HYDROGEN BONDING with POLAR covalent MOLECULES |
| WHAT ensures survival of aquatic animals IN WINTERS when ICE forms on the surface? | THERMAL INSULATION |
| CAGED STRUCTURE WITH LARGE HOLES | ICE |
| AT atomspheric pressure, ice crystallizes in the ...form, but at very low temperatures, it condenses to ... form | HEXAGONAL
CUBIC |
| H2O2 color in pure state | COLORLESS/ VERY PALE BLUE |
| H2O2 STATE when pure | liquid |
| H2O2 SHAPE | NON PLANAR
book shape |
| Moderation of climate and body temperature of living beings _ prop. of water | HIGH HEAT OF VAPORIZATION
AND
HIGH HEAT CAPACITY |
| HOH bond angle in water | 104.5 |
| HO BOND LENGTH IN PEROXIDE GAS | 95 PM |
| OO BOND LENGTH IN PEROXIDE GAS | 147.5 PM |
| HO BOND LENGTH IN PEROXIDE SOLID | 98.8 PM |
| OO BOND LENGTH IN PEROXIDE SOLID | 145.8 PM |
| DIHEDRAL ANGLE (bn HO -OO) in H2O2 GAS | 111.5 |
| DIHEDRAL ANGLE (bn HO -OO) in H2O2 SOLID | 90.2 |
| H20 --- OH BOND LENGTH | 95.7 PM |
| in H202, OO BOND LENGTH IS (SAME/DIFF) IN SOLID/ GAS | DIFFERENT |
| H2O2 acts as an (OXIDIZING/ REDUCING) agent in alkaline media | BOTH |
| H2O2 acts as an (OXIDIZING/ REDUCING) agent in acidic media | BOTH |
| H2O2 decomposes slowly in... and its decom. CATALYSED by ... | LIGHT
METAL/ traces of ALKALI |
| H202 STORED IN ... | WAX LINED GLASS VESSELS or
PLASTIC VESSELS
IN DARK |
| ... is added as STABILIZER to H202 | UREA |
| ... can induce EXPLOSIVE DECOMPOSITION OF H2O2 | DUST |
| H202 | HYDROGEN PEROXIDE |
| PERHYDROL | ANTISEPTIC |
| H202 uses in DAILY LIFE | HAIR BLEACH
DISINFECTANT
ANTISEPTIC |
| H202 used to manufacture ...& ... used in DETERGENTS | SODIUM PERBORATE
PER CARBONATE |
| H202 IS EMPLOYEED IN INDUSTRIES AS ... FOR TEXTILES, LEATHER,OILS, PAPER, FATS, etc | BLEACHING AGENT |
| D20 is used as ... in NUCLEAR reactors | MODERATOR |
| COMMERCIAL production OF DI HYDROGEN (4 WAYS) | 1) ELECROLYSIS of acidified water w PLATINUM electrodes
2) ELECTROLYSIS of aqueous barium hydroxide solution in NICKEL electrodes
3) as a BY PRODUCT in manufacture of sodium hydroxide by electrolysis of BRINE
4) BY REACTION of STEAM with COKE or HYDROCARBONS |
| HIGHEST QUALITY di hydrogen is obtained by | ELECTROLYSING WARM AQUOUS BARIIUIM HYDROXIDE |
| greater ENTHALPY of FORMATION (H2O/D2O) | H2O (-285) wheras D2O (-294) |
