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  1. MT = 13000 (suggesting surface dissociation)

  2. wA = 2RT (suggesting that hydrogen is dissociated into atoms
    when chemisorbed on a nickel surface)

  3. Vm = 225 cm^3 (s.t.p.) g'^1
    a = 7.1 x Hr^5 Pa~l

  4. 530 m^2 g"^1

  5. 47 x 10"^20 m^2

  6. 7.8 m^2 g"^1 (using BET equation)

  7. V/Vm 0.4 0.8 1.2
    A//ads/kJ moP^1 -11.8 -12.7 -9.1
    Values reflect multilayer physical adsorption on a fairly uniform
    solid surface

  8. 0 = 0.1, A#ads = -180 kJ mol~ l
    0 = 0.5, A//ads. = -123 kJ
    Absolute magnitudes suggest chemisorption and relative magni-
    tudes reflect preferential adsorption at the more active sites on
    the solid surface

  9. A/fad,. = -44 kJ moP^1

  10. r = 2.03 nm (assuming zero contact angle, closed cylindrical
    pores, constancy of y with r, equivalence of multilayer adsorption at
    flat and curved surfaces)

  11. (a) p/p 0 = 0.81; (b) plp 0 = 0.90

  12. Fe(lOO), 12.2 x 1014 atoms cm"^2 ;
    Fe(llO), 17.3 x 1014 atoms cnT^2 ;
    Fe(lll), 7.1 x 1014 atoms cm"^2 ;
    Fe(100)-C(2 x 2)-N, 6.1 x 1014 N atoms cm~^2

  13. Wa - 54.0 ml m~^2 , S = -91.5 mJ m~^2

  14. 69°

  15. 145 x 10"^20 m^2

  16. (a) 1 nm; (b) 10 nm; (c) 7 nm; (d) 5 nm

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