Thermal Decompositiin

Question 1

Heating of Oxoacid
1)ous acid
H3PO2—->
2)HClO3—->
3)Parentic acid
H2CO3—->
H2SO4—->
HNO3—->

Answer 1

1)ous acid
H3PO2—->H3PO4 + PH3
2)HClO3—->HClO4 + HCl
3)Parentic acid
H2CO3—->H2O + CO2
H2SO4—->H2O + SO3—-> SO2+1/2O2
2HNO3—->H2O + N2O5—->2NO2+1/2O2

Question 2

Heating of oxide
i)Ag2O—>
ii)PbO2—->
iii)Mn2O7—->
iv)CrO3—->

Answer 2

i)Ag2O—>Ag + O2
ii)PbO2—->PbO + O2
iii)Mn2O7—->MnO2 + O2
iv)CrO3—->Cr2O3 + O2

Question 3

Heating of carbonate
Metal carbonate —->
i)CaCO3—->
ii)Ag2CO3—->
iii)PbCO3.Pb(OH)2—->

Answer 3

Metal carbonate —->Metal Oxide + CO2

i)CaCO3—->CaO + CO2
ii)Ag2CO3—->Ag + O2 + CO2
iii)PbCO3.Pb(OH)2—->PbO + CO2 + H2O

Question 4

Heating of HCO3-,CH3COO-,HCOO-,C2O4-2

i)Ca(HCO3)2—->
ii)(CH3COO)2Ca—>
iii)(HCOO)2Ca—->
iv)CaC2O4—->

Answer 4

Metal x —->Metal carbonate + y
y = x - CO3-2

i)Ca(HCO3)2—->CaCO3 + H2O + CO2
ii)(CH3COO)2Ca—> CaCO3 + CH3COCH3
iii)(HCOO)2Ca—->CaCO3 + HCHO
iv)CaC2O4—->CaCO3 + CO

Question 5

heating of x
v)Ag2C2O4—->
vi)HCOOAg—->
vii)(CH3COO)Ag—->
viii)HCOONa—->

Answer 5

v)Ag2C2O4—->Ag+CO2
vi)HCOOAg—->Ag+CO2+HCOOH
vii)(CH3COO)Ag—->Ag+O2+CO2+CH3COCH3
viii)HCOONa—->Na2C2O4+H2

Question 6

Heating of nitrates
i)LiNO3—->
ii)NaNO3—->

Answer 6

i)LiNO3—->Li2O+NO2+O2
ii)NaNO3—->O2+NaNO2—->Na2O+N2+O2
1)if M !=Na,K,Rb,Cs
metal nitrate—->metal oxide + O2 + NO2
2)if M =Na,K,Rb,Cs
metal nitrate—>metal nitrite + O2

Question 7

Heating of sulphates:
i)CuSO4.5H2O—->
ii)FeSO4.7H2O—->

Answer 7

i)CuSO4.5H2O—->CuSO4.3H2O—>CuSO4.H2O—->CuSO4—->CuO+SO3
ii)FeSO4.7H2O—->FeSO4—->Fe2O3+SO2+SO3

Question 8

Heating of Phosphate
i)H3PO4
ii)NaH2PO4
iii)Na2HPO4
iv)Na3PO4

Answer 8

i)H3PO4—->H4P2O7—->HPO3—->P4O10
ii)NaH2PO4—->NaPO3+H2O
iii)Na2HPO4—>Na4P2O7+H2O
iv)Na3PO4—->no rxn

Question 9

Phosphates
v)NaNH4HPO4.4H2O—>
vi)2MgNH4PO4—->

Answer 9

v)NaNH4HPO4.4H2O—>NaPO3+NH3+H2O
vi)2MgNH4PO4—->2NH3+Mg2P2O7+H2O