Hydrogen Flashcards
Enthalpy of Hydrogen is more like metals or non-metals
non-metals
Hydrogen anion size comparison
F,H,Cl,Br,I
small to Big
Which hydrogen is called heavy hygroden
Deuterium
Which hydrogen isoteop is radioactive and emits what particles
tritium, Beta Particles
Melting Point order of H isotopes
H2,D2,T2
small to Big
density order of isotopes of H
H2,D2,T2
small to Big
bond dissociation order of isotopes of H
H2,D2,T2
small to Big
volatile nature order of isotopes of H isotopes
H2,D2,T2
big to small
High purity H2 is obtained by
electrolysing warm aqueous barium hydroxide solution between nickel electrodes
water-gas, Syn gas meaning, and process of producing it is called and reaction is?
water-gas:- H2 + CO
syn gas:- also called as water gas
coal gasification:- C+H2O—-> CO + H2
The reaction of H with Fluorine,Iodine conditions
hydrogen with fluorine can happen in dark too
hydrogen with iodine will happen in the presence of iodine
Which hydrides have polymeric structure and banana bonds
BeH2 and MgH2
Only d block element which forms a hydride
chromium
CrH
Crystalline structure of ice in atmospheric and low temperatures
at Atmospheric pressure, ice crystallises in hexagonal form
at low temperature, it condenses to cubic form
Mg (HCO3) heating product
Mg(OH)2 + CO2
Ca (HCO3)2 heating product
CaCO3 + H2O + CO2
How to remove temporary and permanent hardness
temporary: - boiling, Clark’s method
permanent: - Calgons method( adding sodium hexametaphosphate also called Calgon) ; treatment with sodium carbonate), ion exchange method also called zeolite process ; synthetic resins method
The structure of hydrogen peroxide is planar or non-planar and the dihedral angle is more in the solid or gas phase?
H2O2 has a non-planar structure with H and H in different planes and has a dihedral angle more in the gas phase as compared to the solid phase
Heavy water
D2O
Peroxide reactions in acidc and basic mediums
CuSO4.5H2O structure
which method is more suitable for preparing deionized water?
synthetic resin method
how is atomic Hydrogen produces?
its produced at high temperature in an electric arc or under UV radiations
whats the dissociation percentage of dihydrogen at 2000K
0.081%
which diatomic molecules bond dissociation is !?
H-H bond dissociation enthalpy is highest
which metal can form interstitial hydride easily
Cr
reactivity of H as compared to halgens is
very low
which planrts consist motly of hydrogen
Jupiter and saturn
why is hydrogen less abudant in earth’s atmosphere
becuaese of its light nature
neutrons in hydrogen , deutrium and tritium
hydrogen: 0
deutrium: 1
tritium: 2
whats water gas?
the mixture of CO and H2
catalyst used in water shift gas
iron chromate
dissociation of dihyrodren in to its atoms at 2000K and 5000K is
2000K= 0.081% 5000K= 95.5%
why is H2 relateively iner at room temperature
High HH bond enthalpy
how is atomic hydrogenproduced
at high temperature in an electric ard or under UV radiation
hydrogenatino of vegeatble oils is done by whichcatlayst?
nickel
hydroformylation of olefin s yeilds?
aldehydes
covalent metal hydrides are
MgH2
BeH2
LiH
eg of electron rich hydirdres
NH3
HF
H2O
which metals form interstitial hydrides
and what abt other metals
Ni
Pd
Ce
Ac
they have lattice different from that of the parent metal
angle of gas pphase water
104.5
what is used in examination of crystals
X rays
one of the reasons why H2O is a great source of dihyrogen?
cause is can be easily reduced to H2 by highly electropositive metals
one of the reasons why H2O is a great source of dihyrogen?
cause is can be easily reduced to H2 by highly electropositive metals
one of the reasons why H2O is a great source of dihyrogen?
cause is can be easily reduced to H2 by highly electropositive metals
reason for strong hydrating tendency of water is
high dielectric constant
eg of interstitial water
BaCl2.2H2O
whats used in removing the temporary hardness of water
boiilng and clark’s method
how are the precipitates removed after boiling hard water
distillation
whats clark’s method
in this method calculated amount of lime is added to hard water
whats causes temporary hardness
Mg and Ca hydrogen carbonates
what causes the permanent hardness of water?
Mg and Ca sulphates and chlorides
how is permanent hardness of water removed
treatment with washing soda, calgons method, ion exchange method, synthetic resins method|
whats calgon
Na6P6O18
what zeolite/permutit
NaAlSiO4
when is permutit/zeolite is said to be used up
when all the sodium in it is used up
whats Synthetic resins method
hard water is softened by using synthetic cation exchangers, this method is more effective than zeolite process
what organic molecule does cation exchange resins contain?
SO3H
To what is R-SO3H changed to? and how?
it is changes to RNa and by treating it with NaCl
whats the principle behind synthetic resins method and why does the water gets acidic
H+ exchanged Na, Ca,Mg ions and other cations present in water his process results in proton release and thus makes water acidic
what happens in anion exchange process
. OH- exchanges for anions like Cl-,HCO3- and SO4 2- present in water
how is H2O2 formed with BaO2
acidifying barium peroxide and removing excess water by evaporation under reduced pressure gives H2O2( see the reaction for better understanding)
what does H2O2 forms in water?
H2O2. H2O
color of H2O2 is
almost colorless(very pale blue)
how is H2O2 marketed?
30% of H2O2 is marketed as 100 volume Hydrogen peroxides. it means on mm of 30% H2O2 solution will give 100 ml of O2 at STP
whats the dihedral angle of H2O2 structure in gas and solid phase
Solid phase: 90.2
Gas phase: 111.5
why cant H2O2 be stored in metal containers?
because metal surfaces act as catalyst for decomposition of H2O@
whats added in H2O2 containers to stabilize it?
Urea
why is H2O2 kept away from dust
cause it can induce explosive decomposition of the compound
