What inspired N. Bartlett for carrying out reaction between Xe and PtF6?
N. Bartlett observed that PtF6 reacts with O2to give an compound O2+ [PtF6]–.
PtF6 (g) + O2 (g) ——–>O2+[PtF6]–
Since the first ionization enthalpy of Xe (1170 kJ mol-1 )is fairly close to that of 02 molecule (1175 kJ mol-1 ), he thought that PtF6 should also oxidise Xe to Xe+. This inspired Bartlett to carryout the reaction between Xe and PtF6. When PtF6 and Xe were made to react, a rapid reaction took place and a red solid, Xe+[PtF6]– was obtained.
Justify the placement of O, S, Se, Te and Po in the same group’of the periodic table in terms of electronic configuration, oxidation state and hydride formation.
Which of the following statements are correct?
(a) Among halogens, radius ratio between iodine and fluorine is maximum.
(b) Leaving F – F bond, all halogens have weaker X – X bond than X – X’ bond in interhalogens.
(c) Among interhalogen compounds maximum number of atoms ate present in iodine fluoride.
(d) Interhalogen compounds are more reactive than halogen compounds.
Discuss the general characteristics of Group 15 elements with reference to their electronic configuration, oxidation state, atomic size, ionisation enthalpy and electronegativity.
How is nitrogen prepared in the laboratory? Write the chemical equations of the reactions . involved.
Reduction potentials of some ions are given below. Arrange them in decreasing order of oxidizing power.
Nitric acid forms an oxide of nitrogen on reaction with P4O10. Write the reaction involved. Also write the resonating structures of the oxide of nitrogen formed.
Phosphorus forms a number of oxoacids. Out of these oxoacids phosphinic acid has strong reducing property. Write its structure and also write a reaction showing its reducing behaviour.
Assertion (A): HNO3 makes from passive.
Reason (R): HNO3 forms a protective layer of ferric nitrate on the surface of iron.
Assertion (A): HI cannot be prepared by the reaction of KI with concentrated H2SO4.
Reason (R): HI has lowest H – X bond strength among halogen acids.
Assertion (A): NaCl reacts with concentrated H2SO4 to give colourless fumes with pungent smell. But on adding MnO2 the fumes become greenish yellow.
Reason (R): MnO2 oxidises HCl to chlorine gas which is greenish yellow.
Why is BiH3 the strongest reducing agent amongst all the hydrides of group 15 elements? (C.B.S.E. 2013)
What happens when white phosphorus is heated with concentrated NaOH solution in an inert atmosphere of CO2?
What are the oxidation states of phosphorus in the following: –
(i) H3PO3 (ii)PCl3
(iii) Ca3P2(iv)Na3PO4
(v) POF3
With which neutral molecule is ClO– isoelectronic? Is this molecule Lewis acid or base ? (Pb. Board 2009)
Arrange the following in the order of property indicated for each set: –
(i) F2 , Cl2 , Br2 , I2 – increasing bond dissociation enthalpy.
(ii) HF, HCI, HBr, HI – increasing acid . strength.
(iii) NH3, PH3, AsH3, SbH3, BiH3 – increasing Sol. base strength.
On addition of cone. H2SO4 to a chloride salt, colourless fumes are evolved but in case of iodide salt, violet fumes come out. This is because
If chlorine gas is passed through hot NaOH solution, two changes are observed in the oxidation number of chlorine during the reaction. These are —— and ——-
Which of the following statements are correct for SO2 gas?
(a) It acts as a bleaching agent in moist conditions.
(b) Its molecule has a linear geometry.
(c) Its dilute solution is used as disinfectant.
(d) It can be prepared by the reaction of dilute H2SO4 with metal sulphide.
Which of the following statements are true?
(a) Only type of interactions between particles of noble gases are due to weak dispersion forces.
(b) Ionisation enthalpy of.molecular oxygen is very close to that of xenon.
(c) Hydrolysis of XeF6 is a redox reaction.
(d) Xenon fluorides are not reactive.
Write a balanced chemical equation, for the reaction showing catalytic oxidation of NH3 by atmospheric oxygen.
Explain why does the stability of oxoacids of chlorine increase in the order given below:
HClO < HClO2 < HClO3 < HClO4
Match the compounds given in Column I with the hybridization and shape given in Column II and mark the correct option.
Assertion (A): SF6 cannot be hydrolysed but SF4 can be.
Reason (R): Six F atoms in SF6 prevent the attack of H2O on sulphur atom of SF6.
An amorphous solid "A"bums in air to form a gas "B"which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous KMnO4 solution and reduces Fe3+ to Fe+2. Identify the solid "A"and the gas "B"and write the reactions involved.
