Home
Class 12
CHEMISTRY
The first ionization energy for Li is 5....

The first ionization energy for Li is 5.4 eV and electron affinity of Cl is 3.61eV. The `DeltaH` (in kJ/mol) for the reaction `Li(g)+Cl(g)rarrLi^(+)+Cl^(-)` is (if resulting ions do not combine with each other) (1eV=`1.6 xx 10^(-19)J)`

A

70

B

100

C

170

D

270

Text Solution

Verified by Experts

The correct Answer is:
C
First ionization potential of Li = 5.4 eV
Electron affinity of Cl = 3.61 eV
We have `DeltaH=I.P.-E.A.`
`=5.4-3.61=1.80eV=1.80xx1.6xx10^(-22)kJ`
`DeltaH=2.86xx10^(-22)kJ`,
for 1 mol Avogadro's number = `6.02 xx 10^(23)`
`DeltaH=2.86xx10^(-22)xx6.02xx10^(23)=170 kJ//"mole"`.
Promotional Banner

Topper's Solved these Questions

  • THERMODYNAMICS AND THERMOCHEMISTRY

    ERRORLESS |Exercise ORDINARY THINKING (Objective Questions) Free energy and Work function|57 Videos

  • THERMODYNAMICS AND THERMOCHEMISTRY

    ERRORLESS |Exercise Critical Thinking (Objective Questions)|63 Videos

  • THERMODYNAMICS AND THERMOCHEMISTRY

    ERRORLESS |Exercise ORDINARY THINKING (Objective Questions) Heat of reaction|174 Videos

  • SOME BASIC CONCEPTS OF CHEMISTRY

    ERRORLESS |Exercise JEE Section (Matrix Match type questions)|3 Videos

Similar Questions

Explore conceptually related problems

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)^(-) .

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.

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?

The IE_(1) of Li is 5.4 eV and IE_(1) of H is 13.6 eV . Calculate the charge acting on the outermost electron of Li atom.