Oxygen Compounds

Question 1

Dioxygen

Isotopes
O2 does not react with?
Oxygen is used in what kind of welding?
Decomposition of H2O2 in presence of what catalyst ?

Answer 1

O16, O17, O18
Au, Pt, some noble gases
Oxyacetylene welding
Finely divided metals and MnO2

Question 2

Simple oxides

Acidic oxide - definition and example
Exception to the general rule “only non metal oxides are acidic”

Basic oxide - definition and examples

Amphoteric oxides
Neutral oxides

Answer 2

SO2, Cl2O7, CO2, N2O5 - oxides that combine with h2o to give an acid
Oxides at higher OS - Mn2O7, CrO3, V2O5

The oxide that gives a base with water. Eg:CaO

Al2O3
NO, CO, N2I

Question 3

Mixed oxides

Answer 3

Pb3O4, Fe3O4

Question 4

Ozone

Reactivity
Prep. % of occurance
Colour (gas, liq, solid)

Answer 4

Highly reactive
O2 passed through electrical discharge. 10% occurance.
Pale blue gas, dark blue liq and violet black solid.

Question 5

What happens if the concentration of ozone increases above ____ ppm

Cause of depleting O3

Answer 5

Above 100 ppm..
Harder to breathe, headache and nausea

Nitrogen oxides (mostly NO - nitric oxide) from exhaust of supersonic jet aeroplanes

Question 6

O3 or O2, thermodynamically stable?
O3 explosive?
Why does it act as a powerful OA?
Quantitative method of estimation of O3 gas

Answer 6

O2
Yes, at high temp. Extremely explosive
Ease to liberate nascent [O]

O3 + excess of KI sol buffered with borate buffer (pH 9.2) –> I2 liberated. This I2 can be titrated against a std sol of sodium thiosulphate.