Home
Class 11
CHEMISTRY
The first IP lithium is 5.41eV and elect...

The first IP lithium is `5.41eV` and electron gain enthalpy of `Cl` is `-3.61eV` . Calculate `Delta H` in `KJ mol^(-1)` for the reaction:
`Li_(g) +Cl_(g) rarr Li_(g)^= +Cl_(g)^(-)`.

Text Solution

Verified by Experts

`Delta H//`molecule of `Li^+` and `Cl^- =IF_1 +` Electron gain enthaply .
` = 5.41 - 3. 61 =1. 80 eV`
` :. Li rarr Li^+ +e , IP_1 +ve`
and ` Cl + e rarr Cl^(-1) ,` Electron gain enthalpy `= -ve`
` :. Delta H//mol=1.8 xx 6. 023xx 10^(23) eV`
`=1.8xx 6. 023 xx 10^(233) xx 1.602 xx 10^(19) J`
` =1. 8 xx 6.023 xx 10^(23) xx 1. 602 xx 10^(19) xx 10^(-3) kJ`
` = 173. 7 kJ`.
Promotional Banner

Topper's Solved these Questions

  • CHEMICAL BONDING

    P BAHADUR|Exercise Exercise2A|101 Videos

  • CHEMICAL BONDING

    P BAHADUR|Exercise Exercise2B|25 Videos

  • ATOMIC STRUCTURE

    P BAHADUR|Exercise Exercise 9|38 Videos

  • CHEMICAL EQUILIBRIUM

    P BAHADUR|Exercise Exercise|134 Videos

Similar Questions

Explore conceptually related problems

The first ionisation potential of Li is 5.4 e V and the electron affinity of Cl is 3.6 eV . Calculate Delta H in kcal mol^(-1) for the reaction Li (g) + Cl (g) to Li^(+) + Cl^(-) Carried out at such low pressures that resulting ions do not combine with each other.

For the reaction : PCl_(5) (g) rarrPCl_(3) (g) +Cl_(2)(g) :

If the first ionization enthalpy of Li is 5.4 eV and the elec- tron gain enthalpy of chlorine is 3.6 eV then the Delta H in kcal/mole for the reaction will be Li(g)+Cl(g) to Li^(+) (g) Cl^(-) (g) (Presume that the pressure is so low that the ions do not combine with each other)

Answer the following question (Based on EA, Delta_(eg)H^(ɵ) and IE ). (a) IE_(1) of Li is 5.4 eV "atom"^(-1) and the EA of Cl is 3.6 eV "atom"^(-1) . Calculate Delta_( r)H^(ɵ) in "kcal mol"^(-1) and kJ mol^(-1) for the reaction Li_((g))+Cl_((g)) rarr Li_((g))^(o+)+Cl_((g))^(ɵ) formed at such a low pressure that resulting ions do not combine with each other. (b) The IE of atoms X and Y are 400 and 300 kcal mol^(-1) respectively. EA's of these atoms are 80.0 and 85.0 K cal mol^(-1) . Explain as which of the atoms has higher EN . ( c) Explain why EA of S is -200 kJ mol^(-1) but the second EA is +649 kJ mol^(-1) ? (d) Which of the following pairs of elements would have more negative electron gain enthalpy (Delta_("eg")H^(ɵ)) ? (i) F or Cl , (ii) O or F (e) What would be the second electron gain enthalpy (Delta_(eg)H_(2)^(ɵ)) of oxygen as positive, more negative or less negative than first (Delta_(eg)H_(1)^(ɵ)) ? Explain. (f) Which has less negative Delta_(eg)H^(ɵ) oxygen or sulphur?