For which of the following process, enthalpy change is positive.
1] F + `e^(-)` `to` `F^(-)`
2] O + `e^(-)` `to` `O ^(-)`
3] O + `2e^(-)` `to` `O^(-2)`
4] H + `e^(-)` `to` `H^(-)`

The process requiring absorption of energy is (1) F to F^(-) (2) Cl to Cl^(-) O to O^(2-) (4) H to H^(-)

Which of the following are green house gases ? (a) CO_2 (b) O_2 (c) O_3 (d) CFC (e) H_2O

In which of the following process maximum energy is released A) S_((g))+e^(-) rarr S_((g))^(-) B) O_((g))^(-) +e^(-) rarr O_((g))^(-2) C) S_((g))^(-)+e^(-) rarr S_((g))^(-2)

In which of the following reactions H_(2)O_(2) acts as reducing agent? (A) H_(2)O_(2)+2H^(+)+2e^(-) to 2H_(2)O (B) H_(2)O_(2)-2e^(-) to O_(2)+2H^(+) (C ). H_(2)O_(2)+2e^(-) to 2OH^(-) (D) H_(2)O_(2)+2OH^(-)-2e^(-) to O_(2)+2H_(2)O

Which of the following set of compounds have peroxide bonds ? 1. O_(2)F_(2) " " 2. H_(2)O_(2) " " 3. H_(2)S_(2)O_(8) " " 4. CrO_(5)

In which of the following reactions H_(2)O_(2) acts as a reducing agent? 1. H_(2)O_(2)+2H^(+)+2e^(-)to2H_(2)O 2. H_(2)O_(2)-2e^(-)toO_(2)+2H^(+) 3. H_(2)O_(2)+2e^(-)to2OH^(-) 4. H_(2)O_(2)+2OH^(-)-2e^(-)toO_(2)+2H_(2)O

From the following E^(o) value of helf cells: (i) A+e^(-)rarr A ^(-) , E^(o) = -0.824 V (ii) B^(-)+e^(-)rarr B ^(2-) , E^(o) = +1.25V (iii) C^(-)+2e^(-)rarr C ^(3-) , E^(o) = -1.25V (iv) D^(-)+2e^(-)rarr D ^(2-) , E^(o) = +0.68V What combination of two half cells would result is a cell with the largest cell potential?

Among the following oxides how many of them are suboxides ? (a) C_(3)O_(2) , (b) N_(2)O , (c ) NO_(2) , (d) CO (e) Fe_(3)O_(4) , (f) KO_(2)

Manganese ions (Mn^(2+)) can be oxidised by Persulphate ions S_(2)O_(8)^(2-) according to the following half-equations, S_(2)O_(8)^(2-)+2e^(-) to 2SO_(4)^(2-) Mn^(2+)+4H_(2)O to MnO_(4)^(-)+4H_(2)O to MnO_(4)^(-)+8H^(+)+5e^(-) How many moles of S_(2)O_(8)^(2-) are required to oxidise 1mole of Mn^(2+) ?

What is the equivalent mass of O_2 in the following reaction , H_2O+1/2O_2+2e^(-)to2OH^(-) ?